Nice visuals, and I hate to be the “keyboard expert” but some of the information is incorrect. When I went to tech school as a diesel mechanic there was a specific class taught on forced air systems like turbos, blowers, superchargers etc, and the basics taught were theres no such thing as a “belt driven turbo” it’s a common misnomer for what is called a centrifugal supercharger or in the auto tuner world they are called “pro chargers”, a turbo charger is always driven by exhaust gas it’s never mechanically driven turbos do suffer from turbo lag which is their down side as the engine has to rev up to build “boost” when you don’t “build boost” you get black exhaust like the Alcos. Super chargers are always driven mechanically either by a belt, chain or gear, powered by the engine itself. The upside to a supercharger is they are always providing “boost” as they are running directly off the engine and thus there’s no lag and no smoke in the system, this is why on EMDs they don’t smoke out the yard, also because of EMDs two stroke design there’s no “intake” stroke of the piston unlike on 4 strokes so they need a blower or supercharger to constantly force air into the piston, later EMDs as well as GMs Detroit Diesels (which are also 2 stroke) began putting turbos on their engines that would feed air into the super chargers that would then push it into the engine, providing a lot of high pressure air into the system, thus giving them more power output. GE runs a pretty standard system of a 4 stroke engine with a big turbo, similar to the Alcos but I believe how GE fixed the “lag” issue was by making their engines idle at a higher RPM which keeps the turbo spun up so there’s not as big of a lag of power to the engine and not as much black exhaust getting dumped. Granted I’m not a locomotive mechanic I’ve only worked on semi and construction equipment engines so I’ve speculated on a few things that I’m not super familiar with. Still a nice video with great scenery and shots of those old alcos
I was going to reply in similar manner. In fact, your insight gave me understanding of how a turbo charged 2 stroke engine could work since there's already a supercharger on it. I read some stories from Milwaukee Road engineers that drove the first gen GE diesels. Part of the reason they disliked them was the horrible lag and delay of response from idle as they throttled up. The lag and inconvenient positioning of controls made the GE take 2nd place for years until the 1990's.
EMD's have a hybrid turbo with a centrifugal clutch which disengages from the engine when enough boost is being produced, also a possible factor in less smoke.
@@BPJJohn I was going to say the same thing about the EMD Turbos they're gear driven with a clutch that disengages when they reach the right rpm and the Exhaust gas pressure keeps them spun up until they go back to idle and the clutch renengages.
A "belt-driven turbo" isn't a turbo at all, but rather a centrifugal supercharger. Turbos require exhaust gasses to spin the turbine wheel which in turn spins the compressor wheel.
Cool video. I once owned a diesel. I once got pulled over. I explained to the cop that when I talked to the mechanics at the dealership about the black smoke the response was "deal with it". He was not happy but I did not get a ticker. By the way, I grew up in the age of steam. I know smoke. I was told that the best engineers could run almost smokeless. An engine belching clouds of black smoke was a sign of a lesser engineer.
EMD doesn't have a fluid coupling in the turbo drive, it has an over-running clutch. It is mandatory because the EMD is a two stroke and the engine won't run without forced induction. At low power the turbo is spun by the crank, but at higher speed the turbo accelerates and the over-running clutch lets go.
@@adik9441 a turbo and a turbosupercharger are the same thing. The intake supercharger is powered by a turbine (hence turbo) powered by exhaust gas. Mechanically coupled superchargers are not turbos by definition.
The real reason they heavily smoke under rapid acceleration is because the turbo (exhaust driven) has insufficient Exhaust gas to match the fuel that's been added, its very common on mechanically Fuel injected diesels, the fuel is matched to the airflow the turbo is predicted to produce, so adding fuel gently notch by notch will limit the black smoke as theres air from the previous notch of power to match the fuel and thus create a leaner AFR and cleaner stack. however to notch up fast will mean fuel is added for selected notch, if its zero to notch 6, the governor will open the governor to notch 6, the air has to catch up, meaning the air fuel ratio is extremely rich (too much fuel, not enough air, heavy black smoke, this is generally inefficient and sustained rich fuel can result in high engine temperatures, excess carbon build up (which usually burns off once the air catches up.) many alcos run around 15psi of inlet manifold pressure in notch 8 full power, which is why they generally made more power in the top end over early roots blown emds, also blowers take horsepower to feed air as a parasitic load. turbos use exhaust gas but the draw back is the time it takes to spool it up to produce the necessary air pressure. this is often part of why alcos can blow glowing ash when the stack clears up. EMD's however are 2 stroke and require intake air to push exhaust gas out of the cylinder, for this reason they use roots blowers, the turbo model had 2 issues to be solved, make more power from the same size engine. EMD overcame the issue with the with a gear driven Turbocharger, so its a blower (similar to a centrifugal supercharger) down low in the rpm. At Notch 5/6 a clutch disengages, allowing exhaust gas to drive what is now a turbocharger, for this reason EMDs don't generally lag, they always have the air the engine and fuel demands by design. and thus it makes these units more efficient from notch 6,7,8 than they can be in lower notches, by having less parasitic load. hope that helps. Former locomotive maintainer and current locomotive driver
Yeah, you explained it pretty well. The smoke is just due a combination of a little bit of turbo lag and mostly the fact that the engine is below its boost threshold. If someone were to add a modern speed-density engine control unit to these old Alcos and gave them a more refined turbocharger, they likely wouldn't smoke much and would essentially be an equivalent to a GE FDL engine.
The biggest reason they smoke much more than any other 4 stroke is that the governors that controlled the racks for the mechanical injectors. GE and in fact many diesel truck engine manufacturers such as mack and caterpillar had mechanical devices operated by intake manifold pressure, that wouldn’t allow the injection pump or control rack into a full fuel position until there was enough boost pressure. Alco’s did not have this and thus when the engineer advanced the throttle the full amount of fuel for the throttle setting was there whether the engine could properly use it or not. Hence why you’d rarely see a older ge smoking like that unless the injection rack was out of adjustment as the engine aged. And why modern locomotives barely smoke at all as they’re electronically controlled and the electronic fuel injectors are controlled via feedback from intake manifold pressure and many other sensors. That coupled with the fact that alco designed their locomotives to take a load on the generator instantly. EMD and GE’s limited how fast their generators took a load to encourage gentler train handling and reduce pull aparts etc. which made alco’s and their almost instant throttle response well liked for switching and other tasks. Coupled further still with how sensitive alco’s are on their fuel injection rack settings and adjustments. A properly adjusted engine will surprisingly smoke very little, but each engine had to pretty much have its unique adjustment and can vary from engine to engine. Many people lack the tools needed and the art of properly maintaining one is one of those pieces of knowledge that unfortunately has been lost to time.
You are 100% correct. The narrator has no real railroad knowledge and is unaware how tough an alco 251 engine is. they can run out of proper tune for years. There is a reason they lasted long after the builder went out of business.
I used to pass by their plant all the time when I was a little kid in Schenectady NY. I remember the locomotives in the yard with liveries from all over the world.
You nailed it. The black smoke is almost always from too much fuel. I grew up near the Alco factory in NY and they were some great looking units - even with black smoke :)
Cool video. You always seem to find the good locations! Minor note on the D&H PA's: they started life with 16-244's, when upgraded to the PA4 by M-K; had 12-251B upgraded to 12-251C (2000hp to 2400hp). When FNM in Mexico restored 19 and 17 they received 12-251B's. Other note; Baldwin's were 4 cycle diesel engines, as were the Lima-Hamilton's. When George Hockaday worked for the D&H, he worked out a new injector cam timing that helped reduce the black smoke on the 244's. This information was used when M-K upgraded the PA's. It should also be understood that as injectors and turbos wear, the combination also contributes to all of the black smoke. Look at freshly overhauled/rebuilt GE or ALCO prime movers and there is very little black smoke. That lag/hiccup is usually a white or whitish-gray color. Regarding the F-M opposed piston engines, I can't recall hearing anything about the exhaust. That is an interesting one. The biggest thing that hurt F-M after the war was a union strike that basically halted their production, 1954 ish IIRC. The PRR, IC and several other railroads had large orders of Trainmasters on the books that FM could not fill. Those railroads ended up shopping elsewhere. EMD 710 series are 2 cycle, the 265H and the new 1010 are 4 cycle.
A belt driven or gear driven compressor that increases air into the engine is called a supercharger. The "turbo" is the turbine that is turned by exhaust gases. A turbine powered supercharger is called a "turbo or turbocharger or turbosupercharger"
I HAVE WORKED ON THE ALCO 251 ENGINES ON SANTA FE AND THERE IS A MECHANICAL LINKAGE ARRANGEMENT THAT ALLOWS OPERATION WITH LESS SMOKE. BASICALLY IT SLOW THE MOVEMENT OF THE INJECTION PUMP LAYSHAFT UNTIL TURBOCHARGER MANIFOLD AIR PRESSURE BUILDS UP TO A CERTAIN VALUE! THIS ADJUSTMENT CAN BE BEST ACCOMPLISHED WHILE THE LOCOMOTIVE IS ON A LOAD BOX RATHER THAN THE ROAD! IF THE SYSTEM IS SET TOO TIGHT IT KEEPS ENGINE FROM ACCELERATING AND IF SET TOO LOOSE WILL ALLOW EXCESS SMOKE! THERE IS A VERY NARROW ADJUSTMENT BAND FOR PROPER ADJUSTMENT! THE BEST CURE FOR THIS PROBLEM WAS MADE BY THE LATE GREAT GEORGE HOCKADAY! HE DEVISED AN ELECTRICAL CONTROL THAT VARIED MAIN GENERATOR EXCITATION ACCORDING TO TURBO PRESSURE OUTPUT! THE FIRST APPLICATION WAS ON THE 4 EX SANTA FE PA-3 LOCOMOTIVES THAT HAD THE 244-16 ENGINES REMOVED AND REPLACED WITH 251 -12 CYLINDER ENGINES. THIS ELIMINATED APPROXIMATELY 80 % OF THE SMOKING!! KEEP THEM ROLLING BROTHERS!! 👍👍
As a US Navy Engineman we had ALCO Diesels on the LST’s 2,750 HP each Two shafts with 3 -V16’s on each shaft. They were, nicknamed the Smokin “T,s” and they were designed to use oil about a gallon a hour if I remember right. That could account for some smoke. The heaviest smoke was when we put the load to them, but smoothed out when the scavenging air took over. Turbos were big heavy monsters about 1,200 lbs. a part of a turbo smashed my thumb. Bad enough to deform it to this day. The exhaust header was tuned. And a finely tuned was done by the cylinder temps and eye amount of fuel going through the injector pump metered to match the other cylinder temps within 50 degrees between each and evert 16 cylinders.
The main reason for smoked 251 Alco engines is bad maintenance. I worked almost 6 years on RS18 , RSD15 , C630 ,C636 and M636 and we not tolerate a smoky engine like that . Most of the locomotives had worked more than 40 years with a major overhaul somewhere between 500,000 and 1,000,000 miles done .x( 10 to 20 years in average ) When we saw an engine smoke like that , it was immediately send for a repair : faulty injector pump , injector or turbocharger. Badly adjusted fuel rack or lot of leaking between the engine and turbocharger . Sometimes a faulty cylinder head valves . After the repair done , I must say that smoke was disappearing. I must admit that today , genuine parts are not available and find good quality spare parts is difficult and expensive . Also , well trained repairman is missing too . When I see an engine smoke like that , I see lot of pollution and $$$$ of fuel .
Yeah, but where do you get new parts if the parts aren't available anymore, oh yeah, buy something and fab it to fit, then you have a bunch of questionable cobbled up locos, but ALCO is out of business am I right? or do they still manufacture replacement parts? You have a great retort but does it have merit where the parent company is gone for 40 years and spare parts a quickly drying up?
Turbos are not belt driven. 2 cycle diesels (EMD) need a blower to run. It’s not a supercharger on a 2 stroke. Common for a 2 stroke to be turbocharged. Detroits were turbocharged as well but again needed the blower to run and blowers were gear driven.
Ouch! Turbos are powered by exhaust gasses; superchargers are powered by belts (or gears). Turbocharged EMDs had both superchargers for low speed operation and turbochargers for higher speeds. As speed increased and the turbo spun up to speed, an overrunning clutch disengaged the supercharger. Alco 251s are still in production at Fairbanks-Morse for industrial use. Two of them power the Kennedy Space Center launch vehicle.
If you ever come to India then you will be able to see ALCO locos running all around India with its distinctive sound we have WDM 2 WDM 3 series actively hauling trains.. Also neighbour like Sri Lanka and Bangladesh use these locos too.
If you were born too late to see and hear these locomotives working in the USA, pay a visit to India. Alco locomotives were built under license there until just a few years ago and there are large numbers of them in use. They sound the same as the ones in this video, and they are well known for making clouds of black smoke for several seconds if the driver quickly applies full power from idle. There are many videos of them on the Internet. The Indian Alco locomotives are very reliable; I have ridden thousands of miles behind them and none have ever broken down.
Indian Railways is now getting new General Electric, EMD , EMDs all are turbo charged engine. Some EMDs sound like air raid sirens... because of their shrill turbos.
any diesel engine will exhaust black smoke when theres too much fuel for whatever the reason , or too little combustion air. Can be turbo lag , leaky , sticking or worn injectors. White smoke can be due to water entering the combustion chamber, or insufficient engine/combustion temperature . Modern diesels tend to not have excessive white or black exhaust
Step one. Make a large wooden box. Step two. Add a generous portion of rocks. Step three. Shake vigorously. Result, ALCO sounds. To add realism burn coal. The gear box on EMD locomotives is not the turbo issue. It is the overrunning sprag clutch that wears out. We have turbos that just recently failed after twenty years of service in our switching operations. Given a choice as a composite locomotive mechanic I will take a turbo every time. Replacement of blowers is a total pain in the …. back. The reason is that blowers have a bunch of different length bolts. You have to keep them all in order and be a contortionist to reach three quarters of them. The hood on turbo engines comes off above the the turbo making the lift painless. Blowers on the other had must come out the sides with minimal clearance. Having worked on some ALCOs and GE locomotives I can honestly say I find them to be junk. Fuel is not the sole reason for engine power. It must have a corresponding amount of air. If it were just the fuel then there would be unlimited power. This is clearly not the case. For instance, the blowers on a 567 v12 are identical to those found on the 567v16. The difference in air delivery is substantial as a twelve cylinder engine requires less air. So how is this accomplished? The gear train on the back of the engine is of different ratios to turn the two blowers on the twelve cylinder unit slower to deliver enough air for 1200 horsepower. Obviously faster on the sixteen to get the 1750 horsepower. Turning the blowers faster can in fact produce more horsepower but has the drawback of overheating the engine. The Crandick learned this lesson the hard way. The turbo units are able to avoid this problem with after coolers. These are water cooled heat exchangers that reduces the compressor air temperatures. If anyone is interested, the turbos come in different sizes as do the after coolers. So far the oldest diesel I have worked on was built in 1941 and works daily in Tipton Indiana. The newest were on the assembly line in Boise Idaho, the MP36-3 and MP40-3 locomotives in 2007. I have also worked steam in Colorado, Kansas and Texas. I used to think Shays were great until I worked on them. I will take a rod engine over a Shay every time.
the first generation 7FDL in imported version of GE U20C are suffer the same, Indonesian Railways are using the model from 1977 until today, i admit its a sight to behold...
Without going overboard on details, ALCo’s that had the proper Turbo/rack settings did not smoke near as bad. They had numerous combinations of specific turbo setting for each engine model. ALCo’s also used GE Buchi turbocharger style that is more complicated and is closer to a centrifugal jet engine. It was and is similar to that used on WW2 planes. Later ALCo’s, specially export models and MLW’s used a more axial design very similar to what is in modern diesels.
A turbocharger is an exhaust driven device and a supercharger is a mechanically. Superchargers were used on early EMD engines as they need to have the exhaust gases scavenged from the cylinder during the exhaust/inlet stroke. This is how the 2 stroke diesel combines the exhaust stroke and inlet stroke used in a 4 stroke engine. When turbocharger became developed sufficiently the supercharger was eliminated but this requires an overrunning clutch on the turbocharger. The turbocharger is driven mechanically to provide the air to scavenge the cylinders at start up and low speed when there is any or sufficient exhaust games to drive the impeller. As the exhaust gases increase do higher engine RPM and power requirements of the engine the clutch is overrun by the turbocharger's shaft speed and the turbocharger is now an exhaust drive device. Not all 2 stroke diesel engines are cam less. The only ones that I am aware of that are is the Fairbanks Morse opposed piston engine as there is no cylinder head. They have ports in the top and bottom portions of the cylinder so the cylinder can be scavenged. EMD engines have a cylinder head with 4 exhaust valves and the related cam and mechanism to operate them. Don't confuse a 2 stroke diesel engine with a 2 stroke gas engine which do not have valves but do have a cylinder head. Turbocharged diesel engines built before the current electronic control used a device called a air/fuel ratio control or sometimes called an aneroid valve. This device acted against the fuel pumps rack to limit it's travel until turbocharger boost was sufficient. The air/fuel ratio control had a tube or hose connected to the inlet manifold and as the air inlet pressure, boost from the turbocharger, was increased it would react on a piston or rubber diaphragm in the control allowing the rack to travel further allowing more fuel delivery to the cylinders. The air/fuel ratio control was a mechanical device that can be adjusted. Adjust it one way and the engine won't have any or very little smoke but will be very lazy to accelerate, adjust it the other way and the engine would be a snappy accelerator but lots of smoke. Fine line to get the engine to have good performance with an acceptable amount of smoke.
There are indeed 2-stroke gasoline engines WITH VALVES, as in Stihl outdoor maintenance products. I recently had the opportunity to work on one, and theres no crankcase, the valves get their lubrication through passageways built into the engine castings, so they can be compliant with EPA exhaust requirements.
2:35 If a turbo has a belt, *its not a turbo, it's a supercharger* . But in this case, the term "supercharger" is too dramatic for its job of being the substitute valvetrain of a *camless 2-stroke diesel* . Since many designs for 2-stroke diesels cant have camshafts & valvetrains, a roots style "blower" is used to help breath more air into the engine
Excellent video. I love seeing the footage and listening to the sound of those Delaware Lackawanna Alcos. Its good to see the former CP big Alco M-636 still operating.
Have a look at some of the Indian railways ALCo's in action. Truly volcanic. I don't know what they are feeding these poor old things, but they really clean up the mosquito problem.
Except when it's a turbocharger on a 2 cycle locomotive that requires a mechanical linkage also to replace the supercharger on starting and at low RPMs.
@@RailsofForney No. The turbocharger is mechanically driven for starting and at idle, and then functions as a supercharger. At higher power levels, it becomes exhaust driven and functions as a turbo-supercharger, which we call turbocharger for short. Some WWII era aircraft were actually twin-charged, having both mechanically driven superchargers and separate exhaust driven turbo-superchargers.
My experience with the Alto's V-12's was as a diesel generator so we could either power the extra refrigerated containers, or shut down the steam plant for repairs. As such we ran them constant speed, usually paralleled with a steam turbine. The extra 'cat in a box" generators were on their own bus and not paralleled. The engines could run 80% or more all day, day after day. We did not low idle them and expect power. Our biggest service issue that I knew of was raw water pumps (SW) (attached to the engine like the JW pump), the fresh water pumps help up much better. Way more reliable than the DD 149 powered generators on some other ships. Have fun
Common-rail (pressurized) fuel systems with electronic injection enabled much better control of fuel delivery to cope with matching fuel to air on transient conditions, like powering up. Like, enabling gradual ramping up of fuel delivery as manifold pressure increased (from more air delivery from turbocharger.)
Good video & glad u are back. A "True" Turbo Charger is exhaust gas driven with a turbine on one end of a shaft and a compressor on the other. Roots and screw type superchargers are mechanically driven, the EMD's have kind of a hybrid design blending the two concepts which is beyond cool. Kind of like a clutched procharger for the low RPMs with a turbine to take over once the exhaust gas volume is enough to spin that thing. Genius. You drove, remember those old silver series Detroit's , like the 8V92tta's turbos? Even they weren't as "cool" that way with turbo's over the roots blowers as the 710's are.
Old diesel engines fuel feeding control is straight, but turbocharger needs more time for make boost pressure. Too much fuel, and not enough air for full combustion in cylinder make black smoke.
Nice video guy. And yes, I'm an ALCO man. One of the problems with the FA and PA ALCO's was that they had traction effort problems. They where slippery. Reading Lines used a lot of ALCO's and where able to get a lot of the indigenous ALCO problems solved. While your one guy on this thread is kind of correct, locomotive prime movers, as well many marine prime movers, their turbo's are both centrifugal (driven by exhaust gas) as well as mechanically (driven by gear). They have fluid coupling *AND* piping for exhaust gas. Under a certain RPM, the turbo is driven by the crank. Once the prime mover gets to a certain load or RPM, the exhaust gas takes over. Is sounds really technical but, its not. One of the other problems ALCO's had was something the old 2 stroke Detroit Diesels had. They would get oil in the air boxes. Detroit (DDA) 2 stroke motors are notorious for being called "leakers" for 2 reasons. They would leak oil from their air box drains, or injest the oil on start up, or if they leaked bad enough, they would blow blue smoke (oil smoke) on any acceleration. The second reason they where called leakers being their injectors would leak. It would cause another indigenous tag name for Detroit as well ALCO's. They would "run away". The motor would take off like some big assed bird. Many had air shut offs on them because there was no other way to shut them down, once they'd run away. ALCO, Detroit, even you larger 2 stroke marine diesels had (before the electronic age) a valve that was connected to the fuel control rail. It would delay the the rail from allowing the injectors to go full fuel for a second or two. There by limiting the black fuel smoke. More often than not, these valves never worked or mechanics would adjust the valve so it wouldn't work, thinking the valve reduced power. When it actually caused an over fuel condition (hence the black smoke) and reduced power. Obviously the new electronic engine controls limits all of this. But, you still have mechanics today who change computer fuel controls, giving a over fuel condition, or what you hear on the street as "rolling coal". When they don't realize, that smoke is not only money going out the exhaust pipe, excessive over fuel robs the power output, especially at low RPM high torque demand.
Usually, a turbocharger is the name used for the exhaust driven compressor, while a mechanically driven unit is called a supercharger. The difference between the two is that the exhaust driven turbine delivers more air as the engine comes under more load, less dependent on engine RPM. Even if the RPM doesn’t change, a turbocharger will increase the engine power output, while a belt or gear driven turbine or compressor delivers the same amount of air until the RPM’s increase. A two stroke diesel often uses both a compressor AND an exhaust driven turbine, and many v-type two cycle engines have one or more exhaust driven turbos for each bank of cylinders. For the two cycle, the mechanical blower is needed for basic operation, and the exhaust driven turbos deliver the extra power.
Love the look and sound of the Alcos. They smoked because they wanted to be a steam loco when they were young. Back in the early 1970s here in New Zealand we got a series of GE U26c locos that sounded and looked (smoke) like these Alcos. They're still operating but have had lots of rebuilds and no smoke these days.
If I'm doing the math correctly, on a 2 stroke engine idling at 275 rpm (about what EMDs were), that would be a little over 4 cylinder firings per second and at 900 rpm (basically wide open throttle) it would be 15 times per second. And on a 4 stroke engine, you cut that number of firings in half due to it firing every other time the piston rises. So there's no way, in my opinion, that you could hear each of 12 or 16 cylinders fire. Don't think most folks realize just how fast the internals of an engine are moving, for example an automotive engine at 3000 rpm is 50 times per second. If my math or logic is incorrect, welcome any corrections.
By their very nature turbochargers are exhaust-driven. Superchargers are mechanically driven. The reason Alcos smoke so much is because of the Woodward fuel governor. When throttled up, the governor increases fuel flow into the cylinders before the turbocharger can supply enough air for complete combustion. It's a transient issue, not considered serious.
did you watch the vid? he mentions that's what it is, but it's caused from sever turbo-lag because of the belt driven turbos experiencing belt slippage.
I can remember them in the later years lugging coal and iron ore drags on the Penn Central (Conrail) Pittsburgh to Cleveland line back in the 70's. Their massive amount of lugging power is why Conrail transferred the big Centuries to Mingo Junction, Ohio specifically to handle those trains. At the time, that was the primary route by which iron ore was hauled from the docks at Cleveland to the big steel centers around Pittsburgh and Youngstown.
I remember the Turbo Trains, mentioned early in the video. Canadian National, later VIA, ran them for several years and I rode on one once. BTW, I used to be a technician with CN Telecommunications and rode the rails a lot, both on passenger and freight trains.
In the mid 1970s I work for the Chicago belt Railroad and was a conductor on these locomotives and please pardon the pun but " they smoke like a freight train!"
Turbo lag (not enough air) was only half the problem; too much fuel was the other. The fuel regulator (made by Woodward Governor was the problem. It was too stupid to retard fuel flow as the throttle opened, so fuel got poured into the cylinders before the turbos could spool up and provide enough air to burn the fuel properly.
Years ago, i played around with model airplane engines, and discovered theyre a 2-stroke diesel with a crude carburetor, no magneto for spark, just a low voltage glowplug, just warm enough to heat the cylinder up, spin the prop, and away she goes. Didnt need any kind of turbo or blower to get the needed power, just adjust that crude carburetor and dont stick your fingers in the propeller 🤔😢❗
So... TL-DR - Alco's smoke because they have turbo lag. GM EMDs don't have (as much) due to how a 2 stroke works. There's a thing with diesels called the "smoke limit" . Essentially, Diesel engines don't *care* about the mixture. If you run them lean, you don't make power, if you keep dumping fuel in you get lots of smoke and diminishing returns...as well as really high EGTs...but we'll get to that. Basically, back when these were built, in the 50s, nobody cared about the smoke. People were used to trains smoking like crazy (Steam locos) and nobody gave a crap about the environment. This meant that Alco could spec a relatively large, simple, turbocharger, and a fuel pump setup for the boost levels it'd produce at given engine speeds. Simple, easy to fix, easy to design, durable. The problem with this lack of complexity is that it makes the locos smoke. A lot. Especially if they're 4 strokes, which Alcos are. Why? Basically, instead of having the fuel pumps have some kind of feedback from the manifold so they'd adjust the fueling based on manifold pressure, they were just configured to put in X amount of fuel at Notch Y. If the turbo wasn't making enough/any boost, the thing would smoke a bunch until the turbo caught up, then there'd be enough air and the exhaust would clean up. This has nothing to do with belts slipping (the superchargers on GM Locos are gear-driven, and required for a 2-stroke Diesel to even run, they *must have* their intake manifold above ambient atmospheric pressure to even run, they can't draw air on their own), It's literally turbo lag. The system on the 567 is a bit weird. It's not *really* a supercharger and it's not *really* a turbocharger, it's both while actually being purely neither. At low speeds it's driven by the crank, at high speeds (when there's enough exhaust volume) it's driven by the exhaust. This however, is *instead of* a roots blower, which I think you've confused here. The short lines that run 567s use the blown variants, the turbocharged variants are the ones using GM's turbo-super-gear-driven-rube-goldberg device. Also, about EGTs, the EGTs would go through the roof on an Alco while it's spinning up that turbo, you need to remember smoke is literally fuel just being blown out the exhaust, it's still able to combust in the manifold on the hot side of the turbo. Also, with a 4 stroke diesel, you need rpms to lower the egts, so an Alco, off idle, being dumped into notch 8, will probably roast it's turbo in a few years, if not sooner, belch a bunch of black smoke, and not be a happy camper. This is in addition to the technology at the time not being where it is now so heat rejection in the turbo was probably not great, so they ate bearings. This why their engines had a bad rap, they weren't reliable because they *couldn't* be given how they were setup.
Awesome video capture of vintage Alco locos pulling heavy loads with great sound. That “chugging” rhythm is unique to Alco locomotives. Although GE locomotives are also a 4-stroke design, they have a different sound.
The Black and Yellow E.M.D s look like old Locamotives and are probably Simalar models to old Utah Railway units that hauled Coal from Carbon County through Spanish Fork Canyon. There are You tube videos about them . I saw them as a Child.
I believe a belt driven turbocharger can be more accurately described as a supercharger. In any case, I've never heard of a toothed Gilmer belt (which any supercharged unit would surely be using) slipping except under the most extreme circumstances . They'll break and/or strip before they slip. Don't know if the theory presented here is correct--it could be something as simple as poor fuel mixture curves. In any case, good vid.
Alco's were mechanical fuel injected. The alco single turbo was very large and takes a lot to get up to operating speed. Alco's were best at high power outputs. But, you can't beat an Alco sound. Instantly recognizable. Cheg chug chug x 16.
Early ALCOs had huge reliability problems that they were unable to sort for years. Eventually the manufacturing processes were sorted but by then it was too late. Superchargers not also have no lag but absorb power. As for Indian ALCOs being smoke free? Errrr..... no. But boy do they give impressive smoke clouds!!
Thanks AC for another informative video today n the Alco engine. Growing up in Los Angeles in the 50's and 60's all diesel threw out large quantities of black smoke, including GMC and Crown Coach buses.
a 'belt driven turbocharger' is a funny name for a supercharger. 1930s airplane engines used gear driven centrifugal superchargers with a fluid coupling or even multiple impellor blades to vary speed and manifold pressure based on altitude to help reduce power loss with the thin air of higher and higher elevations. why something similar couldnt be used on a much newer train to allow it to avoid turbo lag but also be more efficient once it was moving is beyond me.
13:50 That confirmed my speculation as to why they smoked so much. The grade of fuel it was burning was closer to that of ocean going 'diesel' vessels. One or two refinement steps above crude oil.
@@knightsaberami01 That's the engine lugging during turbo lag. Asking an old diesel to produce power before the boost kicks in result in that hard clatter.
Back in the 60's it seemed like all diesels were smoky, really. They all seemed to be incredibly grimy too. However, all trucks were smoky, too, and automobiles blasted an awful lot of foul-smelling and very visible exhaust. Everything was smoky! Even people were smoking (cigarettes.) Times have really changed.
And on top of that all the pump gas was leaded as well 😅 contaminating all the surroundings , our water and soil for decades , people back then just didn’t know a lot about cancer and what causes it, compare to today back then the life was easier but it also wasn’t “free”, many eventually had to pay for it with their health
Funny, our 60s cars didn't smoke. But then they were tuned properly. As they didn't smoke, the only time you would see the exhaust would be on a cold day. Same as today. Now our car built in the 50s was a bit different as you had to add oil to the gasoline when you filled up. By 1962 that was a thing of the past as they had come up with oil injection by then. So much cleaner running two strokes. 3=6.
One of the most problem in ALCOs is the combustion delay period. There are 4 stages of combustion in Compress Ignition Engines. The delay period is too high which causes black smoke. All ALCOS are now uses exhaust driven Turbo Charger where EMD 710 Turbo Super charger. 1-4 notches gear driven then 5-8 exhaust driven. Anyway. ALCO diesels was born in USA but major development R&D was done in INDIAN RAILWAYS. DLW Varanasi (now BLW), DMW (now PLW) Patiala & RDSO, Lucknow took ALCOs to next level. From WDM2 V16 2600HP the ALCO 251B was upgraded to 251C 3100HP WDM3A WDG3A WDP3A, 3300HP WDM3D & 3600HP WDM3F. WDP3A was tested at 180kmph (112.5mph) used to haul Premium passenger trains in INDIAN RAILWAYS. Also CReDI ( common rail electronic direct injection system) technology was implemented some rebuilt WDM3A WDG3A from DMW. RDSO also tried to implement Emission norms in 251C Prime mover but advent of EMD & INDIAN RAILWAYS ELECTRIFICATION made ALCOs out of the game. The very last ALCO manufactured for INDIAN RAILWAYS was WDM3D 11590 in the year 2016 by DMW. Now ALCOS are manufactured in India only for port trust, power plants, colliery sidings, steel plant & for other industrial usage. Also India exported many ALCOs to Bangladesh, Sri Lanka, Mayanmar & many other countries. Nevertheless ALCOS are still manufactured for such market & still ALCOs are competitive in today’s INDIAN RAILWAY’s market. Sadly ALCOs are now phasing out in very fast pace due to 100% railway electrification of Indian Railways but still they are proving their merits. Most reliable, robust & maintenance friendly design Indian Railways ever got. In Dedicated Freight Corridor route some ALCOS still hauls double stack freight trains.
Yes Indian Railways have developed Alco based locomotives which smoke less like WDM 3D with microprocessor control series of Alco based locomotives and WDP 3A series of ALCo locos
Yeah in order to run a turbo on a 2 stroke diesel you need to have a temporary blower to carry the engine till the turbo can take over, but will always be used at low exhaust efficiency, the answer was a clutched turbo one that was directly attached to the prime mover out put by a clutch that could be released when exhaust volume was high enough to take over, the ST70 AH by EMD is set up that way even though it's 4 stroke to reduce emissions in conjunction to EGR. I was going to go off topic on a rant but changed my mind.
Ah, we still see ALCOs today, but back in the older days, old U-Boats(25,28,30)were just as smokey, but with an incredibly healthy chugging. Those old U-Boats were something. They did not sound quite the same as an ALCO.
Not to mention the already well pointed out inaccuracies and just wrong info, using that one loco at steamtown that is smokes notoriously heavy at times is just bad form when the others usually run pretty clean.
I don't care how much they smoked.i love these locomotives. They may not have been popular with the mechanical departments, but they were known for their ability to pull. Heavy trains!
Back in the day when I was in the navy I was on a LST and it was powered by alcos every time we went under the Coronado bridge they would goose it and we would pump out tons of black smoke
So what do you call the gear driven turbochargers on EMD 2 cycle engines? They have a clutch that disengages in N-6 and after that it’s running on the exhaust only.
@@ralfie8801 It's still a turbocharger and it's only gear driven at start up. Since a 2 stroke needs forced air to scavenge the cylinder and until there is sufficient exhaust gasses the turbo needs to be spun by the gear drive to create the scavenge air. But once it's running there is an over-running clutch and allows the turbo to spin faster using the exhaust gasses. ruclips.net/video/hFVJ9Lhhm0I/видео.html
@@inothome To clarify, as a machinist for a class 1 RR, I know what it is and how it works and why, I was just wondering what the OP was going to say about it.
Super chargers are belt driven. Turbo chargers are driven by an exhaust turbine. ALCOs have a big single turbo. GMS were supercharged and either belt or gear driven.
The D&H PA's were built for the Santa Fe with 16 cylinder 244's. D&H rebuilt the 244's in 2 of them. D&H 17 had a 12 cylinder 244 for a short while. All 4 were rebuilt with 12 cylinder 251 engines by Morrison Knudsen.
Nice visuals, and I hate to be the “keyboard expert” but some of the information is incorrect. When I went to tech school as a diesel mechanic there was a specific class taught on forced air systems like turbos, blowers, superchargers etc, and the basics taught were theres no such thing as a “belt driven turbo” it’s a common misnomer for what is called a centrifugal supercharger or in the auto tuner world they are called “pro chargers”, a turbo charger is always driven by exhaust gas it’s never mechanically driven turbos do suffer from turbo lag which is their down side as the engine has to rev up to build “boost” when you don’t “build boost” you get black exhaust like the Alcos. Super chargers are always driven mechanically either by a belt, chain or gear, powered by the engine itself. The upside to a supercharger is they are always providing “boost” as they are running directly off the engine and thus there’s no lag and no smoke in the system, this is why on EMDs they don’t smoke out the yard, also because of EMDs two stroke design there’s no “intake” stroke of the piston unlike on 4 strokes so they need a blower or supercharger to constantly force air into the piston, later EMDs as well as GMs Detroit Diesels (which are also 2 stroke) began putting turbos on their engines that would feed air into the super chargers that would then push it into the engine, providing a lot of high pressure air into the system, thus giving them more power output. GE runs a pretty standard system of a 4 stroke engine with a big turbo, similar to the Alcos but I believe how GE fixed the “lag” issue was by making their engines idle at a higher RPM which keeps the turbo spun up so there’s not as big of a lag of power to the engine and not as much black exhaust getting dumped. Granted I’m not a locomotive mechanic I’ve only worked on semi and construction equipment engines so I’ve speculated on a few things that I’m not super familiar with. Still a nice video with great scenery and shots of those old alcos
I was confused about belt driven turbo as well. Thanks for the clarification. Great video nontheless.
@@scottsmith7051 you’re welcome, rather long winded comment I made but I wanted to clear up technical details for the “gear heads”
I was going to reply in similar manner. In fact, your insight gave me understanding of how a turbo charged 2 stroke engine could work since there's already a supercharger on it. I read some stories from Milwaukee Road engineers that drove the first gen GE diesels. Part of the reason they disliked them was the horrible lag and delay of response from idle as they throttled up. The lag and inconvenient positioning of controls made the GE take 2nd place for years until the 1990's.
EMD's have a hybrid turbo with a centrifugal clutch which disengages from the engine when enough boost is being produced, also a possible factor in less smoke.
@@BPJJohn I was going to say the same thing about the EMD Turbos they're gear driven with a clutch that disengages when they reach the right rpm and the Exhaust gas pressure keeps them spun up until they go back to idle and the clutch renengages.
A "belt-driven turbo" isn't a turbo at all, but rather a centrifugal supercharger. Turbos require exhaust gasses to spin the turbine wheel which in turn spins the compressor wheel.
Cool video. I once owned a diesel. I once got pulled over. I explained to the cop that when I talked to the mechanics at the dealership about the black smoke the response was "deal with it". He was not happy but I did not get a ticker. By the way, I grew up in the age of steam. I know smoke. I was told that the best engineers could run almost smokeless. An engine belching clouds of black smoke was a sign of a lesser engineer.
EMD doesn't have a fluid coupling in the turbo drive, it has an over-running clutch. It is mandatory because the EMD is a two stroke and the engine won't run without forced induction. At low power the turbo is spun by the crank, but at higher speed the turbo accelerates and the over-running clutch lets go.
I am from India and even today alcos have a little bit of turbo delay you can still see black smoke for 10 secs in some variants and it looks awsm
Turbo belt driven? By nature all turbochargers are driven by exhaust gases. Anything mechanically driven is a Supercharger.
they are using the word Turbosupercharger
@@adik9441 a turbo and a turbosupercharger are the same thing. The intake supercharger is powered by a turbine (hence turbo) powered by exhaust gas. Mechanically coupled superchargers are not turbos by definition.
@@mortson978 thanks
Isn't that essentially a centrifugal supercharger like used in cars?
EMD tho
The real reason they heavily smoke under rapid acceleration is because the turbo (exhaust driven) has insufficient Exhaust gas to match the fuel that's been added, its very common on mechanically Fuel injected diesels, the fuel is matched to the airflow the turbo is predicted to produce, so adding fuel gently notch by notch will limit the black smoke as theres air from the previous notch of power to match the fuel and thus create a leaner AFR and cleaner stack. however to notch up fast will mean fuel is added for selected notch, if its zero to notch 6, the governor will open the governor to notch 6, the air has to catch up, meaning the air fuel ratio is extremely rich (too much fuel, not enough air, heavy black smoke, this is generally inefficient and sustained rich fuel can result in high engine temperatures, excess carbon build up (which usually burns off once the air catches up.) many alcos run around 15psi of inlet manifold pressure in notch 8 full power, which is why they generally made more power in the top end over early roots blown emds, also blowers take horsepower to feed air as a parasitic load. turbos use exhaust gas but the draw back is the time it takes to spool it up to produce the necessary air pressure.
this is often part of why alcos can blow glowing ash when the stack clears up.
EMD's however are 2 stroke and require intake air to push exhaust gas out of the cylinder, for this reason they use roots blowers, the turbo model had 2 issues to be solved, make more power from the same size engine.
EMD overcame the issue with the with a gear driven Turbocharger, so its a blower (similar to a centrifugal supercharger) down low in the rpm.
At Notch 5/6 a clutch disengages, allowing exhaust gas to drive what is now a turbocharger, for this reason EMDs don't generally lag, they always have the air the engine and fuel demands by design. and thus it makes these units more efficient from notch 6,7,8 than they can be in lower notches, by having less parasitic load.
hope that helps. Former locomotive maintainer and current locomotive driver
Yeah, you explained it pretty well. The smoke is just due a combination of a little bit of turbo lag and mostly the fact that the engine is below its boost threshold. If someone were to add a modern speed-density engine control unit to these old Alcos and gave them a more refined turbocharger, they likely wouldn't smoke much and would essentially be an equivalent to a GE FDL engine.
The biggest reason they smoke much more than any other 4 stroke is that the governors that controlled the racks for the mechanical injectors. GE and in fact many diesel truck engine manufacturers such as mack and caterpillar had mechanical devices operated by intake manifold pressure, that wouldn’t allow the injection pump or control rack into a full fuel position until there was enough boost pressure. Alco’s did not have this and thus when the engineer advanced the throttle the full amount of fuel for the throttle setting was there whether the engine could properly use it or not. Hence why you’d rarely see a older ge smoking like that unless the injection rack was out of adjustment as the engine aged. And why modern locomotives barely smoke at all as they’re electronically controlled and the electronic fuel injectors are controlled via feedback from intake manifold pressure and many other sensors. That coupled with the fact that alco designed their locomotives to take a load on the generator instantly. EMD and GE’s limited how fast their generators took a load to encourage gentler train handling and reduce pull aparts etc. which made alco’s and their almost instant throttle response well liked for switching and other tasks. Coupled further still with how sensitive alco’s are on their fuel injection rack settings and adjustments. A properly adjusted engine will surprisingly smoke very little, but each engine had to pretty much have its unique adjustment and can vary from engine to engine. Many people lack the tools needed and the art of properly maintaining one is one of those pieces of knowledge that unfortunately has been lost to time.
You are 100% correct. The narrator has no real railroad knowledge and is unaware how tough an alco 251 engine is. they can run out of proper tune for years. There is a reason they lasted long after the builder went out of business.
in Alco boost air pr is input to governor but it is not that sensitive or accurate
Wow that is fascinating! Thanks for sharing. Makes perfect sense
I used to pass by their plant all the time when I was a little kid in Schenectady NY. I remember the locomotives in the yard with liveries from all over the world.
You nailed it. The black smoke is almost always from too much fuel. I grew up near the Alco factory in NY and they were some great looking units - even with black smoke :)
Cool video. You always seem to find the good locations!
Minor note on the D&H PA's: they started life with 16-244's, when upgraded to the PA4 by M-K; had 12-251B upgraded to 12-251C (2000hp to 2400hp). When FNM in Mexico restored 19 and 17 they received 12-251B's.
Other note; Baldwin's were 4 cycle diesel engines, as were the Lima-Hamilton's.
When George Hockaday worked for the D&H, he worked out a new injector cam timing that helped reduce the black smoke on the 244's. This information was used when M-K upgraded the PA's.
It should also be understood that as injectors and turbos wear, the combination also contributes to all of the black smoke.
Look at freshly overhauled/rebuilt GE or ALCO prime movers and there is very little black smoke. That lag/hiccup is usually a white or whitish-gray color.
Regarding the F-M opposed piston engines, I can't recall hearing anything about the exhaust. That is an interesting one. The biggest thing that hurt F-M after the war was a union strike that basically halted their production, 1954 ish IIRC. The PRR, IC and several other railroads had large orders of Trainmasters on the books that FM could not fill. Those railroads ended up shopping elsewhere.
EMD 710 series are 2 cycle, the 265H and the new 1010 are 4 cycle.
The D&H PAs originally were ATSF locomotives, hence the D&H version of the classic Warbonnet paint scheme.
I’m a 80’s baby January of 83 I love emd and alco power awesome video bud
A belt driven or gear driven compressor that increases air into the engine is called a supercharger. The "turbo" is the turbine that is turned by exhaust gases. A turbine powered supercharger is called a "turbo or turbocharger or turbosupercharger"
I HAVE WORKED ON THE ALCO 251 ENGINES ON SANTA FE AND THERE IS A MECHANICAL LINKAGE ARRANGEMENT THAT ALLOWS OPERATION WITH LESS SMOKE.
BASICALLY IT SLOW THE MOVEMENT OF THE INJECTION PUMP LAYSHAFT UNTIL TURBOCHARGER MANIFOLD AIR PRESSURE BUILDS UP TO A CERTAIN VALUE!
THIS ADJUSTMENT CAN BE BEST ACCOMPLISHED WHILE THE LOCOMOTIVE IS ON A LOAD BOX
RATHER THAN THE ROAD!
IF THE SYSTEM IS SET TOO TIGHT
IT KEEPS ENGINE FROM ACCELERATING AND IF SET TOO LOOSE WILL ALLOW EXCESS SMOKE!
THERE IS A VERY NARROW ADJUSTMENT BAND FOR PROPER
ADJUSTMENT!
THE BEST CURE FOR THIS PROBLEM WAS MADE BY THE LATE GREAT GEORGE HOCKADAY!
HE DEVISED AN ELECTRICAL CONTROL THAT VARIED MAIN GENERATOR EXCITATION ACCORDING TO TURBO PRESSURE OUTPUT!
THE FIRST APPLICATION WAS ON THE 4 EX SANTA FE PA-3 LOCOMOTIVES THAT HAD THE 244-16 ENGINES REMOVED AND REPLACED WITH 251 -12 CYLINDER ENGINES.
THIS ELIMINATED APPROXIMATELY 80 % OF THE SMOKING!!
KEEP THEM ROLLING BROTHERS!!
👍👍
Turn caps off
Bro, did you forget to turn off your caps?
If it's belt driven, it's not a turbo. Turbo's are driven off the exhaust gas.
As a US Navy Engineman we had ALCO Diesels on the LST’s 2,750 HP each Two shafts with 3 -V16’s on each shaft. They were, nicknamed the Smokin “T,s” and they were designed to use oil about a gallon a hour if I remember right. That could account for some smoke. The heaviest smoke was when we put the load to them, but smoothed out when the scavenging air took over. Turbos were big heavy monsters about 1,200 lbs. a part of a turbo smashed my thumb. Bad enough to deform it to this day. The exhaust header was tuned. And a finely tuned was done by the cylinder temps and eye amount of fuel going through the injector pump metered to match the other cylinder temps within 50 degrees between each and evert 16 cylinders.
The main reason for smoked 251 Alco engines is bad maintenance.
I worked almost 6 years on RS18 , RSD15 , C630 ,C636 and M636 and we not tolerate a smoky engine like that .
Most of the locomotives had worked more than 40 years with a major overhaul somewhere between 500,000 and 1,000,000 miles done .x( 10 to 20 years in average )
When we saw an engine smoke like that , it was immediately send for a repair : faulty injector pump , injector or turbocharger.
Badly adjusted fuel rack or lot of leaking between the engine and turbocharger . Sometimes a faulty cylinder head valves .
After the repair done , I must say that smoke was disappearing.
I must admit that today , genuine parts are not available and find good quality spare parts is difficult and expensive .
Also , well trained repairman is missing too .
When I see an engine smoke like that , I see lot of pollution and $$$$ of fuel .
Yeah, but where do you get new parts if the parts aren't available anymore, oh yeah, buy something and fab it to fit, then you have a bunch of questionable cobbled up locos, but ALCO is out of business am I right? or do they still manufacture replacement parts? You have a great retort but does it have merit where the parent company is gone for 40 years and spare parts a quickly drying up?
Turbos are not belt driven. 2 cycle diesels (EMD) need a blower to run. It’s not a supercharger on a 2 stroke. Common for a 2 stroke to be turbocharged. Detroits were turbocharged as well but again needed the blower to run and blowers were gear driven.
Ouch! Turbos are powered by exhaust gasses; superchargers are powered by belts (or gears). Turbocharged EMDs had both superchargers for low speed operation and turbochargers for higher speeds. As speed increased and the turbo spun up to speed, an overrunning clutch disengaged the supercharger.
Alco 251s are still in production at Fairbanks-Morse for industrial use. Two of them power the Kennedy Space Center launch vehicle.
If you ever come to India then you will be able to see ALCO locos running all around India with its distinctive sound we have WDM 2 WDM 3 series actively hauling trains.. Also neighbour like Sri Lanka and Bangladesh use these locos too.
They are becoming increasingly rare, I have not seen one on a passenger train in a long time, only electrics and EMDs.
If you were born too late to see and hear these locomotives working in the USA, pay a visit to India. Alco locomotives were built under license there until just a few years ago and there are large numbers of them in use. They sound the same as the ones in this video, and they are well known for making clouds of black smoke for several seconds if the driver quickly applies full power from idle. There are many videos of them on the Internet. The Indian Alco locomotives are very reliable; I have ridden thousands of miles behind them and none have ever broken down.
Or just come to the north east! We still use plenty of them here! GVT still uses an all Alco roster to move fright through the mountains.
Indian Railways is now getting new General Electric, EMD , EMDs all are turbo charged engine. Some EMDs sound like air raid sirens... because of their shrill turbos.
any diesel engine will exhaust black smoke when theres too much fuel for whatever the reason , or too little combustion air.
Can be turbo lag , leaky , sticking or worn injectors.
White smoke can be due to water entering the combustion chamber, or insufficient engine/combustion temperature .
Modern diesels tend to not have excessive white or black exhaust
The smoke was very useful when we first introduced remote controlled helpers because we could see three plumes of smoke and know all was ok
Step one. Make a large wooden box.
Step two. Add a generous portion of rocks.
Step three. Shake vigorously.
Result, ALCO sounds.
To add realism burn coal.
The gear box on EMD locomotives is not the turbo issue. It is the overrunning sprag clutch that wears out. We have turbos that just recently failed after twenty years of service in our switching operations.
Given a choice as a composite locomotive mechanic I will take a turbo every time. Replacement of blowers is a total pain in the …. back.
The reason is that blowers have a bunch of different length bolts. You have to keep them all in order and be a contortionist to reach three quarters of them. The hood on turbo engines comes off above the the turbo making the lift painless. Blowers on the other had must come out the sides with minimal clearance.
Having worked on some ALCOs and GE locomotives I can honestly say I find them to be junk.
Fuel is not the sole reason for engine power. It must have a corresponding amount of air. If it were just the fuel then there would be unlimited power. This is clearly not the case.
For instance, the blowers on a 567 v12 are identical to those found on the 567v16. The difference in air delivery is substantial as a twelve cylinder engine requires less air. So how is this accomplished? The gear train on the back of the engine is of different ratios to turn the two blowers on the twelve cylinder unit slower to deliver enough air for 1200 horsepower. Obviously faster on the sixteen to get the 1750 horsepower. Turning the blowers faster can in fact produce more horsepower but has the drawback of overheating the engine. The Crandick learned this lesson the hard way. The turbo units are able to avoid this problem with after coolers. These are water cooled heat exchangers that reduces the compressor air temperatures. If anyone is interested, the turbos come in different sizes as do the after coolers.
So far the oldest diesel I have worked on was built in 1941 and works daily in Tipton Indiana. The newest were on the assembly line in Boise Idaho, the MP36-3 and MP40-3 locomotives in 2007.
I have also worked steam in Colorado, Kansas and Texas. I used to think Shays were great until I worked on them. I will take a rod engine over a Shay every time.
Did not know this. Alcos are my favorite to model in ho. Thanks very much 😊👍!
the first generation 7FDL in imported version of GE U20C are suffer the same, Indonesian Railways are using the model from 1977 until today, i admit its a sight to behold...
We used c636 in north west Australia. I was told it was not smoke, it is an efficiency haze.
Without going overboard on details, ALCo’s that had the proper Turbo/rack settings did not smoke near as bad. They had numerous combinations of specific turbo setting for each engine model. ALCo’s also used GE Buchi turbocharger style that is more complicated and is closer to a centrifugal jet engine. It was and is similar to that used on WW2 planes.
Later ALCo’s, specially export models and MLW’s used a more axial design very similar to what is in modern diesels.
A turbocharger is an exhaust driven device and a supercharger is a mechanically. Superchargers were used on early EMD engines as they need to have the exhaust gases scavenged from the cylinder during the exhaust/inlet stroke. This is how the 2 stroke diesel combines the exhaust stroke and inlet stroke used in a 4 stroke engine. When turbocharger became developed sufficiently the supercharger was eliminated but this requires an overrunning clutch on the turbocharger. The turbocharger is driven mechanically to provide the air to scavenge the cylinders at start up and low speed when there is any or sufficient exhaust games to drive the impeller. As the exhaust gases increase do higher engine RPM and power requirements of the engine the clutch is overrun by the turbocharger's shaft speed and the turbocharger is now an exhaust drive device. Not all 2 stroke diesel engines are cam less. The only ones that I am aware of that are is the Fairbanks Morse opposed piston engine as there is no cylinder head. They have ports in the top and bottom portions of the cylinder so the cylinder can be scavenged. EMD engines have a cylinder head with 4 exhaust valves and the related cam and mechanism to operate them. Don't confuse a 2 stroke diesel engine with a 2 stroke gas engine which do not have valves but do have a cylinder head.
Turbocharged diesel engines built before the current electronic control used a device called a air/fuel ratio control or sometimes called an aneroid valve. This device acted against the fuel pumps rack to limit it's travel until turbocharger boost was sufficient. The air/fuel ratio control had a tube or hose connected to the inlet manifold and as the air inlet pressure, boost from the turbocharger, was increased it would react on a piston or rubber diaphragm in the control allowing the rack to travel further allowing more fuel delivery to the cylinders. The air/fuel ratio control was a mechanical device that can be adjusted. Adjust it one way and the engine won't have any or very little smoke but will be very lazy to accelerate, adjust it the other way and the engine would be a snappy accelerator but lots of smoke. Fine line to get the engine to have good performance with an acceptable amount of smoke.
There are indeed 2-stroke gasoline engines WITH VALVES, as in Stihl outdoor maintenance products. I recently had the opportunity to work on one, and theres no crankcase, the valves get their lubrication through passageways built into the engine castings, so they can be compliant with EPA exhaust requirements.
Belt slippage on a turbo? If so, isn't that called a supercharger or blower as turbos are spun by the exhaust?
It`s called centrifugal supercharger.
2:35 If a turbo has a belt, *its not a turbo, it's a supercharger* . But in this case, the term "supercharger" is too dramatic for its job of being the substitute valvetrain of a *camless 2-stroke diesel* .
Since many designs for 2-stroke diesels cant have camshafts & valvetrains, a roots style "blower" is used to help breath more air into the engine
A belt driven Turbo ? No mate, that’s a suoercharger !
Excellent video. I love seeing the footage and listening to the sound of those Delaware Lackawanna Alcos. Its good to see the former CP big Alco M-636 still operating.
Have a look at some of the Indian railways ALCo's in action. Truly volcanic. I don't know what they are feeding these poor old things, but they really clean up the mosquito problem.
We have an ALCO RS3 that runs around my neighborhood. Easy to find just look for the moving car fire.
I did s job at Alco Power in Watertown
What a place !?
Right outta the dark ages
"Why Alcos Smoke So Much"
Because it looks cool.
No smoke no fun, hein.😎
*Alco Soot-Train!*
Fun fact: belt-driven turbochargers are called superchargers.
Except when it's a turbocharger on a 2 cycle locomotive that requires a mechanical linkage also to replace the supercharger on starting and at low RPMs.
@@ostlandr so the engine is twincharged?
@@RailsofForney No. The turbocharger is mechanically driven for starting and at idle, and then functions as a supercharger. At higher power levels, it becomes exhaust driven and functions as a turbo-supercharger, which we call turbocharger for short.
Some WWII era aircraft were actually twin-charged, having both mechanically driven superchargers and separate exhaust driven turbo-superchargers.
A turbo is a supercharger that is driven with exhaust gas. Superchargers that are belt driven are referred to as superchargers.
My experience with the Alto's V-12's was as a diesel generator so we could either power the extra refrigerated containers, or shut down the steam plant for repairs. As such we ran them constant speed, usually paralleled with a steam turbine. The extra 'cat in a box" generators were on their own bus and not paralleled. The engines could run 80% or more all day, day after day. We did not low idle them and expect power. Our biggest service issue that I knew of was raw water pumps (SW) (attached to the engine like the JW pump), the fresh water pumps help up much better. Way more reliable than the DD 149 powered generators on some other ships. Have fun
i love the sound of low rpm combined with turbo whine :D
Common-rail (pressurized) fuel systems with electronic injection enabled much better control of fuel delivery to cope with matching fuel to air on transient conditions, like powering up. Like, enabling gradual ramping up of fuel delivery as manifold pressure increased (from more air delivery from turbocharger.)
Good video & glad u are back. A "True" Turbo Charger is exhaust gas driven with a turbine on one end of a shaft and a compressor on the other. Roots and screw type superchargers are mechanically driven, the EMD's have kind of a hybrid design blending the two concepts which is beyond cool. Kind of like a clutched procharger for the low RPMs with a turbine to take over once the exhaust gas volume is enough to spin that thing. Genius. You drove, remember those old silver series Detroit's , like the 8V92tta's turbos? Even they weren't as "cool" that way with turbo's over the roots blowers as the 710's are.
Old diesel engines fuel feeding control is straight, but turbocharger needs more time for make boost pressure. Too much fuel, and not enough air for full combustion in cylinder make black smoke.
According to Gale Banks,,,,,, waisted H.P.!
I had a lot of "I didn't know that" moments. Now I know. Thank you AC. Excellent video.
It's amazing how much power those traction motors have...
Nice video guy. And yes, I'm an ALCO man. One of the problems with the FA and PA ALCO's was that they had traction effort problems. They where slippery. Reading Lines used a lot of ALCO's and where able to get a lot of the indigenous ALCO problems solved. While your one guy on this thread is kind of correct, locomotive prime movers, as well many marine prime movers, their turbo's are both centrifugal (driven by exhaust gas) as well as mechanically (driven by gear). They have fluid coupling *AND* piping for exhaust gas. Under a certain RPM, the turbo is driven by the crank. Once the prime mover gets to a certain load or RPM, the exhaust gas takes over. Is sounds really technical but, its not. One of the other problems ALCO's had was something the old 2 stroke Detroit Diesels had. They would get oil in the air boxes. Detroit (DDA) 2 stroke motors are notorious for being called "leakers" for 2 reasons. They would leak oil from their air box drains, or injest the oil on start up, or if they leaked bad enough, they would blow blue smoke (oil smoke) on any acceleration. The second reason they where called leakers being their injectors would leak. It would cause another indigenous tag name for Detroit as well ALCO's. They would "run away". The motor would take off like some big assed bird. Many had air shut offs on them because there was no other way to shut them down, once they'd run away. ALCO, Detroit, even you larger 2 stroke marine diesels had (before the electronic age) a valve that was connected to the fuel control rail. It would delay the the rail from allowing the injectors to go full fuel for a second or two. There by limiting the black fuel smoke. More often than not, these valves never worked or mechanics would adjust the valve so it wouldn't work, thinking the valve reduced power. When it actually caused an over fuel condition (hence the black smoke) and reduced power. Obviously the new electronic engine controls limits all of this. But, you still have mechanics today who change computer fuel controls, giving a over fuel condition, or what you hear on the street as "rolling coal". When they don't realize, that smoke is not only money going out the exhaust pipe, excessive over fuel robs the power output, especially at low RPM high torque demand.
People smoked too much in the 1950s… Alcos were normal. 😉 Thanks for the history AC. 🤠👍
Usually, a turbocharger is the name used for the exhaust driven compressor, while a mechanically driven unit is called a supercharger. The difference between the two is that the exhaust driven turbine delivers more air as the engine comes under more load, less dependent on engine RPM. Even if the RPM doesn’t change, a turbocharger will increase the engine power output, while a belt or gear driven turbine or compressor delivers the same amount of air until the RPM’s increase. A two stroke diesel often uses both a compressor AND an exhaust driven turbine, and many v-type two cycle engines have one or more exhaust driven turbos for each bank of cylinders. For the two cycle, the mechanical blower is needed for basic operation, and the exhaust driven turbos deliver the extra power.
Love the look and sound of the Alcos. They smoked because they wanted to be a steam loco when they were young. Back in the early 1970s here in New Zealand we got a series of GE U26c locos that sounded and looked (smoke) like these Alcos. They're still operating but have had lots of rebuilds and no smoke these days.
You are correct. Poorly maintained 244 engines smoked enough that PA units were called "honorary steam engines"
If I'm doing the math correctly, on a 2 stroke engine idling at 275 rpm (about what EMDs were), that would be a little over 4 cylinder firings per second and at 900 rpm (basically wide open throttle) it would be 15 times per second. And on a 4 stroke engine, you cut that number of firings in half due to it firing every other time the piston rises. So there's no way, in my opinion, that you could hear each of 12 or 16 cylinders fire. Don't think most folks realize just how fast the internals of an engine are moving, for example an automotive engine at 3000 rpm is 50 times per second. If my math or logic is incorrect, welcome any corrections.
EMDIdle at 200 rpm at low idle
I worked on them back in the early 70’s. Leaked oil especially on the traction motors
Those off centre headlights on the M420 hits me right in the OCD.
By their very nature turbochargers are exhaust-driven. Superchargers are mechanically driven.
The reason Alcos smoke so much is because of the Woodward fuel governor. When throttled up, the governor increases fuel flow into the cylinders before the turbocharger can supply enough air for complete combustion. It's a transient issue, not considered serious.
Black smoke is unburned diesel fuel. Usually over fueled for power and piston ring lubrication.
did you watch the vid? he mentions that's what it is, but it's caused from sever turbo-lag because of the belt driven turbos experiencing belt slippage.
I can remember them in the later years lugging coal and iron ore drags on the Penn Central (Conrail) Pittsburgh to Cleveland line back in the 70's.
Their massive amount of lugging power is why Conrail transferred the big Centuries to Mingo Junction, Ohio specifically to handle those trains. At the time, that was the primary route by which iron ore was hauled from the docks at Cleveland to the big steel centers around Pittsburgh and Youngstown.
I remember the Turbo Trains, mentioned early in the video. Canadian National, later VIA, ran them for several years and I rode on one once.
BTW, I used to be a technician with CN Telecommunications and rode the rails a lot, both on passenger and freight trains.
In the mid 1970s I work for the Chicago belt Railroad and was a conductor on these locomotives and please pardon the pun but " they smoke like a freight train!"
Turbo lag (not enough air) was only half the problem; too much fuel was the other. The fuel regulator (made by Woodward Governor was the problem. It was too stupid to retard fuel flow as the throttle opened, so fuel got poured into the cylinders before the turbos could spool up and provide enough air to burn the fuel properly.
Wow, at 14:30 a full set of DL motive power all with the same paint scheme! Looks good!
EMD ENGINES with blowers were not considered supercharged. They were considered naturally aspirated.
Years ago, i played around with model airplane engines, and discovered theyre a 2-stroke diesel with a crude carburetor, no magneto for spark, just a low voltage glowplug, just warm enough to heat the cylinder up, spin the prop, and away she goes. Didnt need any kind of turbo or blower to get the needed power, just adjust that crude carburetor and dont stick your fingers in the propeller 🤔😢❗
There is lots of Alco in here India too here fanclub settled for this smoke and typical acceleration sound
in those days, if it wasn't smokin, it wasn't gettin enough fuel
So...
TL-DR - Alco's smoke because they have turbo lag. GM EMDs don't have (as much) due to how a 2 stroke works.
There's a thing with diesels called the "smoke limit" . Essentially, Diesel engines don't *care* about the mixture. If you run them lean, you don't make power, if you keep dumping fuel in you get lots of smoke and diminishing returns...as well as really high EGTs...but we'll get to that.
Basically, back when these were built, in the 50s, nobody cared about the smoke. People were used to trains smoking like crazy (Steam locos) and nobody gave a crap about the environment. This meant that Alco could spec a relatively large, simple, turbocharger, and a fuel pump setup for the boost levels it'd produce at given engine speeds. Simple, easy to fix, easy to design, durable.
The problem with this lack of complexity is that it makes the locos smoke. A lot. Especially if they're 4 strokes, which Alcos are.
Why?
Basically, instead of having the fuel pumps have some kind of feedback from the manifold so they'd adjust the fueling based on manifold pressure, they were just configured to put in X amount of fuel at Notch Y. If the turbo wasn't making enough/any boost, the thing would smoke a bunch until the turbo caught up, then there'd be enough air and the exhaust would clean up.
This has nothing to do with belts slipping (the superchargers on GM Locos are gear-driven, and required for a 2-stroke Diesel to even run, they *must have* their intake manifold above ambient atmospheric pressure to even run, they can't draw air on their own), It's literally turbo lag.
The system on the 567 is a bit weird. It's not *really* a supercharger and it's not *really* a turbocharger, it's both while actually being purely neither. At low speeds it's driven by the crank, at high speeds (when there's enough exhaust volume) it's driven by the exhaust. This however, is *instead of* a roots blower, which I think you've confused here. The short lines that run 567s use the blown variants, the turbocharged variants are the ones using GM's turbo-super-gear-driven-rube-goldberg device.
Also, about EGTs, the EGTs would go through the roof on an Alco while it's spinning up that turbo, you need to remember smoke is literally fuel just being blown out the exhaust, it's still able to combust in the manifold on the hot side of the turbo. Also, with a 4 stroke diesel, you need rpms to lower the egts, so an Alco, off idle, being dumped into notch 8, will probably roast it's turbo in a few years, if not sooner, belch a bunch of black smoke, and not be a happy camper. This is in addition to the technology at the time not being where it is now so heat rejection in the turbo was probably not great, so they ate bearings.
This why their engines had a bad rap, they weren't reliable because they *couldn't* be given how they were setup.
Awesome video capture of vintage Alco locos pulling heavy loads with great sound. That “chugging” rhythm is unique to Alco locomotives. Although GE locomotives are also a 4-stroke design, they have a different sound.
The Black and Yellow E.M.D s look like old Locamotives and are probably Simalar models to old Utah Railway units that hauled Coal from Carbon County through Spanish Fork Canyon. There are You tube videos about them . I saw them as a Child.
I believe a belt driven turbocharger can be more accurately described as a supercharger. In any case, I've never heard of a toothed Gilmer belt (which any supercharged unit would surely be using) slipping except under the most extreme circumstances . They'll break and/or strip before they slip. Don't know if the theory presented here is correct--it could be something as simple as poor fuel mixture curves. In any case, good vid.
ALCO fans must love the fleet DL operates in and around Scranton. Railfans are always out along the Pocono line.
Alco's were mechanical fuel injected. The alco single turbo was very large and takes a lot to get up to operating speed. Alco's were best at high power outputs. But, you can't beat an Alco sound. Instantly recognizable. Cheg chug chug x 16.
To answer the question that you had asked in this video , Baldwin locomotives used 4 cycle diesel fuel as well .
4 cycle diesel fuel? WTF?
Still like the sound of an Alco.Unique from GM and GE.
There's absolutely no way a belt could withstand the speed and temperature of a turbo!!!!!!!!!!
Live right there in the city of Scranton I see them all the time they are work horses
I work on and still maintain a S16-60 prime mover power plant. The Alco likes to be at full power.
Belt driven is a supercharger as used on GMs. Turbos are driven by exhaust gases and so run for free.
Early ALCOs had huge reliability problems that they were unable to sort for years. Eventually the manufacturing processes were sorted but by then it was too late.
Superchargers not also have no lag but absorb power.
As for Indian ALCOs being smoke free? Errrr..... no. But boy do they give impressive smoke clouds!!
I thought it was about why alcoholics smoke so much, but this one was interesting also.
Thanks AC for another informative video today n the Alco engine.
Growing up in Los Angeles in the 50's and 60's all diesel threw out large quantities of black smoke, including GMC and Crown Coach buses.
No such thing as a belt driven turbo. Might be a supercharger but most of those for the big diesels were gear driven.
the Baldwin diesels were all 4 cycle.. either straight 6 or straight 8
a 'belt driven turbocharger' is a funny name for a supercharger. 1930s airplane engines used gear driven centrifugal superchargers with a fluid coupling or even multiple impellor blades to vary speed and manifold pressure based on altitude to help reduce power loss with the thin air of higher and higher elevations. why something similar couldnt be used on a much newer train to allow it to avoid turbo lag but also be more efficient once it was moving is beyond me.
13:50 That confirmed my speculation as to why they smoked so much. The grade of fuel it was burning was closer to that of ocean going 'diesel' vessels. One or two refinement steps above crude oil.
Bunker C fuel was often used since it was cheaper than refined diesel.
Is that why the engines are so noisy, knocking, at 8:30?
@@knightsaberami01 That's the engine lugging during turbo lag. Asking an old diesel to produce power before the boost kicks in result in that hard clatter.
@warmstrong5612 thanks for the explanation 👍
Back in the 60's it seemed like all diesels were smoky, really. They all seemed to be incredibly grimy too. However, all trucks were smoky, too, and automobiles blasted an awful lot of foul-smelling and very visible exhaust. Everything was smoky! Even people were smoking (cigarettes.) Times have really changed.
And on top of that all the pump gas was leaded as well 😅 contaminating all the surroundings , our water and soil for decades , people back then just didn’t know a lot about cancer and what causes it, compare to today back then the life was easier but it also wasn’t “free”, many eventually had to pay for it with their health
Funny, our 60s cars didn't smoke. But then they were tuned properly. As they didn't smoke, the only time you would see the exhaust would be on a cold day. Same as today. Now our car built in the 50s was a bit different as you had to add oil to the gasoline when you filled up. By 1962 that was a thing of the past as they had come up with oil injection by then. So much cleaner running two strokes. 3=6.
Seen a train little over a year ago , c44 wouldnt stop smoking and it had a deeper chug than normal
Great camera work! And, just learned some important details about the diesel locomotive races. Thank you for including those weighty tidbits.
One of the most problem in ALCOs is the combustion delay period. There are 4 stages of combustion in Compress Ignition Engines. The delay period is too high which causes black smoke. All ALCOS are now uses exhaust driven Turbo Charger where EMD 710 Turbo Super charger. 1-4 notches gear driven then 5-8 exhaust driven. Anyway. ALCO diesels was born in USA but major development R&D was done in INDIAN RAILWAYS. DLW Varanasi (now BLW), DMW (now PLW) Patiala & RDSO, Lucknow took ALCOs to next level. From WDM2 V16 2600HP the ALCO 251B was upgraded to 251C 3100HP WDM3A WDG3A WDP3A, 3300HP WDM3D & 3600HP WDM3F. WDP3A was tested at 180kmph (112.5mph) used to haul Premium passenger trains in INDIAN RAILWAYS. Also CReDI ( common rail electronic direct injection system) technology was implemented some rebuilt WDM3A WDG3A from DMW. RDSO also tried to implement Emission norms in 251C Prime mover but advent of EMD & INDIAN RAILWAYS ELECTRIFICATION made ALCOs out of the game. The very last ALCO manufactured for INDIAN RAILWAYS was WDM3D 11590 in the year 2016 by DMW. Now ALCOS are manufactured in India only for port trust, power plants, colliery sidings, steel plant & for other industrial usage. Also India exported many ALCOs to Bangladesh, Sri Lanka, Mayanmar & many other countries. Nevertheless ALCOS are still manufactured for such market & still ALCOs are competitive in today’s INDIAN RAILWAY’s market. Sadly ALCOs are now phasing out in very fast pace due to 100% railway electrification of Indian Railways but still they are proving their merits. Most reliable, robust & maintenance friendly design Indian Railways ever got. In Dedicated Freight Corridor route some ALCOS still hauls double stack freight trains.
Lots of room for improvement of old ALCO diesel engines. We have 'em here in PA. Smoke belching monsters..
Yes Indian Railways have developed Alco based locomotives which smoke less like WDM 3D with microprocessor control series of Alco based locomotives and WDP 3A series of ALCo locos
Thanks for that info.
Yeah in order to run a turbo on a 2 stroke diesel you need to have a temporary blower to carry the engine till the turbo can take over, but will always be used at low exhaust efficiency, the answer was a clutched turbo one that was directly attached to the prime mover out put by a clutch that could be released when exhaust volume was high enough to take over, the ST70 AH by EMD is set up that way even though it's 4 stroke to reduce emissions in conjunction to EGR. I was going to go off topic on a rant but changed my mind.
Ah, we still see ALCOs today, but back in the older days, old U-Boats(25,28,30)were just as smokey, but with an incredibly healthy chugging.
Those old U-Boats were something. They did not sound quite the same as an ALCO.
I love that Alco sound, thanks for posting a great video..
Thanks for watching Larry.
What makes Alcos sound so great.
Not to mention the already well pointed out inaccuracies and just wrong info, using that one loco at steamtown that is smokes notoriously heavy at times is just bad form when the others usually run pretty clean.
GE U-23 B, Do have 3x haust output on 'Cold Starts' and other locomotives at times.
I don't care how much they smoked.i love these locomotives. They may not have been popular with the mechanical departments, but they were known for their ability to pull. Heavy trains!
Back in the day when I was in the navy I was on a LST and it was powered by alcos every time we went under the Coronado bridge they would goose it and we would pump out tons of black smoke
If it's exhaust-driven it's a turbocharger.
If it's mechanically-driven it's a supercharger. A Roots blower is a supercharger.
On a 2 stroke diesel it is a blower.
So what do you call the gear driven turbochargers on EMD 2 cycle engines? They have a clutch that disengages in N-6 and after that it’s running on the exhaust only.
@@ralfie8801 It's still a turbocharger and it's only gear driven at start up. Since a 2 stroke needs forced air to scavenge the cylinder and until there is sufficient exhaust gasses the turbo needs to be spun by the gear drive to create the scavenge air. But once it's running there is an over-running clutch and allows the turbo to spin faster using the exhaust gasses.
ruclips.net/video/hFVJ9Lhhm0I/видео.html
@@hoverhead047 Diesels can have either, a turbo or blower and they are different. As T Bunker explained perfectly.
@@inothome
To clarify, as a machinist for a class 1 RR, I know what it is and how it works and why, I was just wondering what the OP was going to say about it.
Super chargers are belt driven. Turbo chargers are driven by an exhaust turbine. ALCOs have a big single turbo. GMS were supercharged and either belt or gear driven.
And, later generations also had turbochargers for aspiration once well above idle. Mechanically aspirated (NOT supercharged) at and off-idle until.
ALCO has a 1 star rating for environmental friendly
The D&H PA's were built for the Santa Fe with 16 cylinder 244's. D&H rebuilt the 244's in 2 of them. D&H 17 had a 12 cylinder 244 for a short while.
All 4 were rebuilt with 12 cylinder 251 engines by Morrison Knudsen.