I'm a dealership Mercedes technician, and I always wondered what that noise was. This video is awesome! You've got a great modification there. I'd be curious to see how it holds up after a few tens of thousands of miles.
@@archangel3237 cavitation will destroy anything. look up cavitation damage on ship propellers. those don't touch anything but water and yet they can get chewed up pretty badly.
@@adams4100 i dont think they do because those gears will have a constant film of oil and wont ever touch each other to wear down. Well, they will wear down but probabbly outlive the engine/car. Edit: spelling
@@adams4100 How would they only last a month? They are on 2 individually driven, timed shafts. They literally don't do anything other than push against the fluid.
@@adams4100 No they do not run against each other. It is the job of the other gears that are pressed on to keep the shafts synchronized. (the ones that pump only oil with no air entrained with it, and are precision ground from steel as you said because they actually operate against each other.) The lobe design he made isn't even capable of driving the other shaft if the other gears were to fail. If they were asked to do any work, it would literally just jam up.
Regarding the material chemistry, the aluminum is a poor material, as what wears the gears out is not the contact as they are made of the same material and are lubed, its the cavitation proces which is also part of the reason for your noise, as its imploding air by crushing it and doing that chunks the gears or the walls depending on the pump type, taking small fragments of material from the part where the cavitation happened... Aluminum being turd soft is not the best thing, especially for the initial gears which see the largest air bubbles... Steel should be used as was for the factory gears, but apart from the material, great design! I'm not saying the aluminum wont work, but it will wear out much quicker as the wear as stated above in pumps if ran lubed is rarely caused by the contact of the parts which are of same material, but rather caused by impurities/solids in the fluid pumped and cavitation process...
Cavitation is the real problem and the finite fatigue life of Aluminum. Further the is no reason to have made them out of Aluminum, no useful weight savings plus extra cost over steel. The only reason I could see to use Aluminum is machining time (assuming only having HSS tooling) but this shouldn't be a concern given the product and application. Now if you're building a car were every gram counts then this is a good idea.
Yes I'm opinion like you say aluminum sound good but not in the right place for doing the job because one little piece of aluminum so to the crankshaft and the engine blloout.
He didn't talk about the level of the press-fit either, or thermal growth. That bore is going to grow ~.0025" in operation. Will it still be a good fit with hot oil wicking in the material, lubricating it nicely? Will it crack from the stress when he parks it in a -20c lot? Steel really would have been the better choice.
He could even machine three small alignment slots on the side of the gear, then machine an alignment bracket which keys into the slots. Then just press em both in at once.
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this! PLEASE HELP!
Press fitting aluminum onto a steel shaft - how does the difference in thermal expansion between the two metals affect the fit when the engine heats up?
@@xfmotorsports I know it would mean additional machining, but adding a keyway to both shafts would allow perfect alignment of the lobe gears without any possibility of expansion related failure. It would also make assembly/alignment dramatically easier. For an alternate lobe shape, look up "Waukesha Pumps". These are food grade product pumps used in the food/dairy industry that are basically just large slow oil pumps. We used to use them to pump heated peanut butter to packaging machines. What a mess to clean up!
The gears don't need to touch for brinelling to become a problem as unfiltered oil debris inevitably becomes embedded in the aluminum rotors as they squeeze together. The gears should be designed with cast iron or steel.
I wouldn't use these without an oil filter installed for sure. Most dry sump pumps have aluminum gears and I wouldn't run without an oil filter with those either. Good point
I actually love this noise! It's how you know you have a 5.5! When I got a C55 for my wife I was stoked to find it made the same start up noise as my SL55!
For getting the gears aligned on the shaft, a 3D printed jig would have helped get it spot on. SLA printers are very cheap now and are perfect for this sort of thing. Great job using your eyecrometer though!
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this! PLEASE HELP!
For future scale up and ease of assembling....wouldn't it be a good idea to make your new gears parts fixed on the shaft using a key? Yes, you have to cut a slot in the shaft, but you can use the existing one as reference. Once the CNC has made this slot, the rest is "easy". Takening apart and reassemble wouldn't be a specialist, like yourself, to line it up perfectly. 👍Love your videos!! 😃😎
Keyways must have play in them in order to be assembled, so, as well as adding more manufacturing steps and a stress riser that could initiate fatigue cracking in the shaft and gear, doing this will not locate the gears on the shafts as precisely as a press fit. It also add radial movement to the gears, which will likely create noise through imbalance as the gears will naturally tend to run off centre with the shafts, which can't happen on press fitted parts.
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this! PLEASE HELP!
As a machinist, I would say that the use of aluminum in this application is insufficient. I would be very worried about the aluminum spinning on the shaft causing catastrophic failure. That being said, your ingenuity and execution was spot on. You did a really good job. I dont know what cost is associated with producing these lobes, but im assuming less that 50$ for material and machine run time. Take a lobe and a straight cut gear to a tool grinding shop they can precision grind id and profile with tighter tolerances and better press fit. Very awesome video! And the shop cam select the correct material based on hardness of straight gear.
I'm surprised it was worth it to go with aluminum rather than a more thermally stable metal like steel. With steel couldn't you tighten up the clearance between the gears more because they will expand less, ending up with a more efficient pump?
This is a great idea, but what's the thermal expansion effects going to be like? Aluminum has about double the coefficient of linear thermal expansion compared to steel, so when submersed with hot oil for hours, could the new gears begin to slip from their press fit on the shaft and hit each other?
This concept intrigues me. I know oil pressure is largely formed by the bearings, so is there any way to keep the oil pressure down after you beef up the pump? Do more/bigger oil passages do anything about oil pressure? What if you simply used a smaller pan and reduced the amount of oil in the system? Less oil would mean the pump will have periods during which it pushes less or no oil, so I'd guess that's actually a lubrication concern for the pump and the bearings, not to mention a concern for the longevity of the oil between changes. Thoughts?
@@youmakeitwhatitis Higher pressure means the film layer in the bearings can support more load. Not a bad thing at all. The only cost is power to provide that pressure. Probably minuscule.
@@youmakeitwhatitis All pressure pumps have a bypass of some sort to control pressure; usually part of he pump but sometimes fitted in the main oil gallery. If you increase the flow of the pump significantly, you then need to increase the size of the bypass. However, since this is a scavenging stage, there should be no significant pressure. I don't think that's what the OP had in mind though. I think he is talking about surface tension. The faster a solid strikes a fluid, the more that fluid behaves like a solid. Hit a fluid fast enough and it can well be "harder" than the solid that hit it. I can see how this property could be a problem in a scavenge pump at very high RPM.
He hasn't altered the pump or output performance of the drive pumps, only the transfer pump in stage one that's essentially a siphon from one sump to the other. Frankly the whole system is a little overdesigned, as an easier way is to simply have a larger sump and more oil (which is better for cooling) and then the active pickup is never starved for oil. Anyway, this modification will only affect how quickly the stage one pump transfers and dries the first sump and keeps the active second sump fed. As he states in the video, the face cut gears were much quieter when moving material, but the motor spends very little time in that condition, once the stage 1 moves all the available oil from that sump, they go dry/partially dry and whine loudly from then on. The active side pumps (that push oil pressure to feed the motor) weren't changed other than fixing the second set of gears to act as the drive gear for the second shaft. That should have negligible effect (if any) on the pump characteristics and performance of the active system
Have you factored thermal expansion of aluminium in your design? If not you could have problems when engine oil gets hot - press fit could get loose because steel shaft expand less than aluminium gears and tolerances between gears could shrink too much.
If you plan on doing more of these you could make an installation fixture which both gears sit inside of in the correct orientation, center distance and axial offset offset so you can press fit both at the same time, that should remove any potential for them to be out of phase. It would basically just be a stepped piece of material with a close tolerance to the outside of each gear and two through-holes so you can press both to full depth in one operation.
The three lobe pump has been out there for a while and companies like Komatsu, CAT, Hitachi etc have been using them in their hydraulics. But you have shown a good application in Mercedes Benz engines to rid of the whinning noise. Maybe you could get in touch with Daimler Benz AG, their head office and show these improved results and who knows they might use this designs in their engines. The only concern is the higher flow (so the pressure release valve needs adjusting) and using the softer aluminum for the lobes. The aluminum could wear out due to cavitation and friction from molecules of oil. Steel would be a better material. Finally, you can time the lobes perfectly and easily by using a jig to line them up while assembling. And if you have ideas that have not been patented before, register a patent or design and reap the benefits of your invention.
Just curious if this vast improvement in oil flow could cause over pressuring elsewhere in the system? Thanks for your talent and patience in creating this product and video.
That is a substantial display, the additional problem is the standard gears break down the long chain molecules that give viscosity, much faster than your design because you don't put the oil in "shear", a real problem with hot engines, lots of pressure, and there is no recovery when the molecular structure is broken, cooling doesn't restore viscosity, and it foams far faster than "sound oil, unscathed". Very much different. Thanks for the demonstration.
You could make a special press tool that holds both of the lobed gears in the proper orientation and allows both of them to be pressed on simultaneously. Also, since you used Aluminum, heating the lobed gears will make installing them much easier, they should FALL into place if they are heated, avoiding the need for pressing altogether. Combine heat and an installation jig and you'd have a relatively easy installation process.
It's a very tight fit. You can't expand aluminum that much without melting. Making a fixture might make it easier but because of the backlash in the gears it still won't be a 100%, unless the gears on the other side have a fixture as well
@@eformancePLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this! PLEASE HELP!
Awesome video and its interesting how rotary style lobes (don't know what you actually call them) are coming back into fashion for water pumps / dry sumps etc. I learnt about them from my commercial rotary compressor only draw back from my understanding is tolerances play a huge part in them working efficiently or at all. Keep it up i shall be back to watch more
Couple of points correct me if im wrong, 1 most of the whine should be coming from the supercharger 2 aluminium is not going to last those gears need to be steel, thermal expansion etc etc 3 when you spun up the old pump the drill was at a moderate speed then there was a noticeable speed increase when you spun up the new pump you can see this if you focus on the clamps on the "flexy" shaft. so i would question the flow differance. The idea is good and sound i think the pump gears just need to be steel or the oil could go full "twilight" on you
Hopefully the heads can drain the extra flow, I know that's an issue on the RB engines. Also, you should probably do a pressure test also, not just a flow test. As I'm sure you know, one does not always indicate the other.
Be aware of aliminium doesn't hold too much with cavitation....for prototype serve the purpose but you should make them in steel and heat treat..... When assemble try to heat the gear...it will much easy to put it in place and adjust..
Interesting gear design taken straight from multi lobed superchargers ( Rootes, Sprintex ) that have been around for many decades . The supercharger rotors are actually machined helical but theoretically they too , do not actually come into contact with each other except when there is an idler gear backlash and contact. The Sprintex units have coated rotors . Basically a pump is a pump whether hydrodynamic or aerodynamic . An improved version of this pump would incorporate the helix .
If you plan to do this mod many times I think it would be a good idea to fabricate a tool that slots into the first gear and the second shaft in order get the second gear in position.
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this! PLEASE HELP!
it is similar to root blower. to reduce the noise use helical gear instead of spur gear the pair you're using, but assembling with helical gear is more tricky
Double the lobes.... and 6:50 that gap is to decrease wear and if you know how surface tension works..... The oil in that gap develops a sheet around the sprocket/lobe
Props on thinking outside the box but a little food for thought, most aftermarket oil pump gears I've seen are made from heat treated chromoly. There must be a reason the oem doesn't use aluminum maybe from galling issues.
You should have just keyed the shafts and made a slot in those lobed gears and then just drop them in place. Wouldn't have required such precious press fitting and the assembly could have been disassembled later on.
My only worry here would be that there might be enough backlash in the gears that are synchronising the shafts in the pump to allow the lobed elements to contact each other when the engine overruns. Gear pump gears tend to be a pretty tight fit together to keep the pump efficient though, so hopefully not an issue until there's a lot of wear on it.
I know it's an up charge - but for consistency is there any way to make a tool for locating / pressing them in at the same time? (if you had a press). Knowing most people - selling something w/ such tight installation tolerances might get you more negative feedback than positive?
@@xfmotorsports Try to 3D print a case to hold the 2 gears in correct position; when the first gear in place; use the 3d printed holder to hold the 2nd gear in correct position then press in. it may have higher chance to success.
Man, you made my day. I own and drive a M272 with this whining noise for about 10 years now and was always wondering what it is. As I exchanged the timing chain and pulleys for some other reason 😎, I already suspected the oilpump and it‘s drive chain. As always: excellent job, nicely documented. Thank you very much!!
272 is a different engine, and uses a different pump. 272/273 doesn't suffer from this problem. Check your drive belt pulleys, AC compressor, or PS pump. Those are the main culprits for noise on that engine.
thanks for the laugh material on that stock pump. what about using key instead of press fit for both ease of assembly and serviceability?. or key on one side and locking screw on another side for adjustability?
After pondering this for a little while I realized one very large flaw in the testing. The stock gears being flat cut have a significant amount more resistance to turn than your new design. Which is great, especially for noise. However because you're only using a maximum canadian tire drill, you can see the clamps are spinning at different rates between the new and old design. So even though it appears the new design flows more, it's because the drill is spinning at a higher RPM due to less resistance. The drill does not have the required torque or control to spin both pumps at the exact same RPM to test the flow difference, even just visually.
After a almost 24 minute video, awesome results.. but why the heck didn’t you incorporate a finalized ending result with this pump inside one of the two vehicles at the beginning of the video? Or was there still the “Mercedes whine”? I’m sad to not see the pump put into one of these cars..
If they were heat shrunk on, he wouldn't get them off with that gear puller and that little wrench. And "heart shrink" is ambiguous, as you can hear ANY part to get it on. He could have heated his new aluminum gear up with a heat gun and put it on. Would that make it a great shrink installation just because he heated it? All that matters is the degree of interference. A part that has enough interference, where you need to heat it to install it, is going to have so much cleaning force that he wouldn't get it if with that gear puller.
@@xenonram so you saw the same video everyone else saw, or something else? He's using aluminum gears on a steel shaft. Ie, pressing aluminum gears onto something that's harder will wallow out the hole. This isn't steel on steel.
I bet if you made the "drive" gears helical, even something small like 10 degrees you would go even further in reducing the noise. Just have to consider side load at that point. Just a thought if you wanted to take it further.
I absolutely obsess over this guy's content because of my even-worse obsession of M113 powered AMG cars, but I have to wonder if sacrificing the many thousands spent by MB's R&D to manufacture an oil pump that has proven to last forever but makes an audible whine when cold should be replaced by something completely new and custom just for the sake of getting rid of the whine.
I'm concerned that the aluminium gears won't last, they will wear and put debris into your oil. Also the thermal expansion could loosen then off the shaft. I'd be tempted to remake these in hardened steel.
So, is the speed difference we see in the input shaft due to the added resistance from the old gear's friction fitting? If actually spun at the same speed is the flow actually that much higher? I would think the volume of oil pumped would be equal to the engagement area of the teeth times the number of teeth. Without the exact numbers it's hard to say, but it looks as if there is less 'total tooth volume' per rotation on the new design which would equate to less oil pumped per turn. When spun by an engine that won't notice the torque difference needed and that is set to maintain a given RPM in any case, I have a feeling the flow rate is actually lower on the new set of gears.
So you thinking about a complete package switch out and a customer ships a core and you assemble all? Charge a core return? I have a sl55 and would have interest to do this as long as I had to only put the complete pump in. Great video. Great content!
Interesting project, however, you still have TWO steel spur gear pumps in that assembly which continue to make noise. Gear pumps are noisier because the gears have to make contact to transfer power from one gear to another, your lobe pump can not work independently, it has to rely on external gears to work, and those gears will always generate noise, so it is kind of defeating the purpose, not to mention it makes the overall pump bigger and more costly, maybe that's why lobe pumps are never used in engines lubrication systems
Its cool that you tried and did it man.... but I would have just bought a drysump pump there are so many good vendors out there. Its just alot of effort and time vs relatively inexpensive pumps considering.
Explain more about the dimple please This is only the scavenging side so pressure isnt as important as flow rate, the other stages provide the pressure
Maybe machine index marks on each lobe and each indentation that shows the center of them? Or idea 2: Maybe like a sheet of plastic that needs to fit through them to confirm the gap?
The thermal expansion coefficient of aluminum is a good bit higher than steel after some time the aluminum gears will loosen and most likely touch then destroy each other, A better material would have been copper which has a close expansion coefficient to steel but ultimately the final gear should have been steel, especially given how time consuming the assembly is ur not going to want to keep replaying them and dealing with shards of aluminum in ur oil
Interesting but with litigation being what it is, a long term testing regime might prove cost effective. You might consider hard anodising to reduce cavitation damage, or better consider steel. The idea seems good but possibly under developed.
really curious about how the aluminum gears hold up. im not sure wear is the only concern, my first thought was cavitation damaging the peaks and valleys of the gears (where cavitation is most likely to occur) i wonder what a set looks like after a few thousand miles.
The straight gears have the noise at startup only and then quiet down quite quickly. Is this because the pump is saturated with oil or all the oil has been scavenged from the front sump? And to be clear this 'new' gear chamber just moves oil from the front sump to the back right? It is a very annoying noise tbh - and having it quieter is much preferred - its just a bit difficult to pick up the different noises generated with the impact gun in the background! Do the other straight gears also make this noise? Why is the front gear the loudest? Personally I would have made the gears out of steel - but I assume this is just a case of changing the base stock during manufacture? Press fitting ally onto steel gets me a bit worried about the ally fracturing over time - when under load for many hours and heat cycles especially given the very tight tolerances.
Suggestion for the gear alignment: Having some sort of fixture you machine like a thick piece of plexiglass or other cheap, rigid material that could be machined as an outside fixture to keep the gears rotated into their proper 'phase.' I say something cheap so you can ship it out to the customers with the gears.
AWESOME! I could not find an affordable oil pump for my w210. My engine is ok but my oil pump is shot . Previous owner threw a belt and kept driving. it sucked the front main seal into the timing cover- dumped all the oil and clogged the pickup tube. The motor runs fine but was making a horrendous noise from the oil pump.
Great video and explanation about the noise source. I thought this noise was coming from the chain. My W163 which has a M112 has little noise, but my w210 M111 has way more winning noise, and mostly on idle. Now I know ...
According to the number of gears set teeth in the oil pump, the oil pressure is different with the rpms of the oil pump gears and it’s teeth. For the performance engine, that design is good for avoiding oil starvation at high rpms in engine but not for normal every day driving engine, it will or can starve oil at engine idling.
Yes which is probably why he didn't change the pressure stage gears and left those stock. He only changed the gears that take oil from the front sump and dumps it into the rear sump.
You will be getting problems with the hydraulic lifters due to the pulsation of the oil pressure. Cavitation will also be a problem (Air in the Oil) They know what they do at AMG.
Interesting video, do you know if the oil sump O-ring issue is also affecting S55 and CL55 due to equivalent O-ring used for collecting the oil? Can the oil pump chain tensioner be replaced from underneath without removing the engine from the car.
No, S55 and CL55 have a different pump. They don't use an o-ring to seal the collector. I believe the upper/lower pans and timing cover need to be removed to replace the oil pump guide and spring
Awesome job, very complicated work to get it right.... are you worried about cavitation damaging the lobes over time? I’ve seen it damage steel gears over time, not sure how aluminum will hold up
Whoa, did you consider like a twin screw design where you have 2 different lobes that fit to each other? Or a slight helix to help compress from pan side to port side?
Hello, this has been tremendously informative and educational - I would REALLY hope you keep making videos with such detail. I have several concerns about the pump, though: It seems like you increased the flow that the pump creates per rotation. Since this is a dry sump this might not be a problem, but doesnt that increase the load on the shafts and consequently on the steel gears which are used to time the shaft? Another problem which might result from this: With the increased flow and and therefore lower pressure at the inlet of the scanvenging pump, i suspect there might be a higher chance of cavitation to occur at high rpm. Thankfully you made the lobes out of aluminium so it will be visible in no time if such a thing happens. Great vid, though.
Тест на то работает или нет новая шестерня? Думаю надо было проверить какое давление он создает и точно замерить производительность, а то столько работы и просто в тазу побулькали.
You are gonna mess with hydraulic film between parts with this flow rate . Try mixing high viscosity oil with previous grade oil. Or add good quality oil additives. This is must to compensate the effect of new oil flow rate.
this whole time I thought that the whine was coming from the alternator, I even called it the supercharged alternator!
I thought it was the power steering
@@project_amg the noise is quite different than power steering whine. It sounds more like a roots/screw type supercharger whine
@@project_amg mine is power steering. But also this pump noise. On baby benz m112k
Well, you can still call it the supercharged oil pump!
@@lucasatsuoito7978 when you need to make the oil faster
I'm a dealership Mercedes technician, and I always wondered what that noise was. This video is awesome! You've got a great modification there. I'd be curious to see how it holds up after a few tens of thousands of miles.
Lol same. Sometimes when i start one of them i make the noise with my voice 😜
Longevity can be corrected by changing the alloy or the heat treatment used if it happen to become an issue.
The new gears don't actually touch anything at all, no contact no wear.
@@archangel3237 cavitation will destroy anything.
look up cavitation damage on ship propellers. those don't touch anything but water and yet they can get chewed up pretty badly.
@@archangel3237 lol that's not how that works bud. Everything touches *something* in this universe.
This guy out-German'd the Germans
Apart from the fact they will last about month.... they need to be made from steel....
@@adams4100 i dont think they do because those gears will have a constant film of oil and wont ever touch each other to wear down. Well, they will wear down but probabbly outlive the engine/car.
Edit: spelling
@@adams4100
How would they only last a month?
They are on 2 individually driven, timed shafts. They literally don't do anything other than push against the fluid.
@@nickopedia5669 and each other.... we reproduce oil pumps and the gears are precision ground steel for a reason.
@@adams4100
No they do not run against each other.
It is the job of the other gears that are pressed on to keep the shafts synchronized. (the ones that pump only oil with no air entrained with it, and are precision ground from steel as you said because they actually operate against each other.)
The lobe design he made isn't even capable of driving the other shaft if the other gears were to fail. If they were asked to do any work, it would literally just jam up.
This channel is a big motivation ☝️literally keeping me in engineering school without wanting to give up all together
This makes me regret studying finance instead of engineering 😔
@@Rogerfuk I studied mechanical engineering, and now I can't find a job 💪
@@kasparsjansons9220 epic win
@@kasparsjansons9220 where do you live?
Keep it up
Netflix: are you still watching?
Someones daughter: 20:02
Oh god
Bruh
🤣
Regarding the material chemistry, the aluminum is a poor material, as what wears the gears out is not the contact as they are made of the same material and are lubed, its the cavitation proces which is also part of the reason for your noise, as its imploding air by crushing it and doing that chunks the gears or the walls depending on the pump type, taking small fragments of material from the part where the cavitation happened... Aluminum being turd soft is not the best thing, especially for the initial gears which see the largest air bubbles... Steel should be used as was for the factory gears, but apart from the material, great design! I'm not saying the aluminum wont work, but it will wear out much quicker as the wear as stated above in pumps if ran lubed is rarely caused by the contact of the parts which are of same material, but rather caused by impurities/solids in the fluid pumped and cavitation process...
Cavitation is the real problem and the finite fatigue life of Aluminum.
Further the is no reason to have made them out of Aluminum, no useful weight savings plus extra cost over steel. The only reason I could see to use Aluminum is machining time (assuming only having HSS tooling) but this shouldn't be a concern given the product and application.
Now if you're building a car were every gram counts then this is a good idea.
Yes I'm opinion like you say aluminum sound good but not in the right place for doing the job because one little piece of aluminum so to the crankshaft and the engine blloout.
He didn't talk about the level of the press-fit either, or thermal growth. That bore is going to grow ~.0025" in operation. Will it still be a good fit with hot oil wicking in the material, lubricating it nicely? Will it crack from the stress when he parks it in a -20c lot? Steel really would have been the better choice.
Idk about steel..Brass is usually used in the scavenge pumps that I've seen
Might be worth machining an assembly jig for the pump gears. Maybe just a bracket to hold the gears in alignment.
He could even machine three small alignment slots on the side of the gear, then machine an alignment bracket which keys into the slots. Then just press em both in at once.
@@blipman17 maybe not slots just holes for alignment pegs that would be on some thick backplate to use on the press
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this!
PLEASE HELP!
Press fitting aluminum onto a steel shaft - how does the difference in thermal expansion between the two metals affect the fit when the engine heats up?
Aluminum expands more but the press fit is much tighter than it will ever expand to. I heated them till they started melting. Still remained tight
They should never be much more than 220 degrees like the oil in the pan....
@@xfmotorsports I know it would mean additional machining, but adding a keyway to both shafts would allow perfect alignment of the lobe gears without any possibility of expansion related failure. It would also make assembly/alignment dramatically easier. For an alternate lobe shape, look up "Waukesha Pumps". These are food grade product pumps used in the food/dairy industry that are basically just large slow oil pumps. We used to use them to pump heated peanut butter to packaging machines. What a mess to clean up!
@Vivid Media yeah but not at any temp close to 220 degrees
More then that I would be in fear off electro-chemical corrosion, those two metals gives up some voltage together
18:40 ah yes, the sound of german engineering
The gears don't need to touch for brinelling to become a problem as unfiltered oil debris inevitably becomes embedded in the aluminum rotors as they squeeze together. The gears should be designed with cast iron or steel.
I wouldn't use these without an oil filter installed for sure. Most dry sump pumps have aluminum gears and I wouldn't run without an oil filter with those either. Good point
I actually love this noise! It's how you know you have a 5.5! When I got a C55 for my wife I was stoked to find it made the same start up noise as my SL55!
Should have got a c32! But hard to find
@@nickmarshall2676 No way! The C55 is so much more lovelier, it's still a hard find too! Both great cars though.
For getting the gears aligned on the shaft, a 3D printed jig would have helped get it spot on. SLA printers are very cheap now and are perfect for this sort of thing. Great job using your eyecrometer though!
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this!
PLEASE HELP!
Has a CNC but no press 😂❤️❤️❤️
For future scale up and ease of assembling....wouldn't it be a good idea to make your new gears parts fixed on the shaft using a key? Yes, you have to cut a slot in the shaft, but you can use the existing one as reference. Once the CNC has made this slot, the rest is "easy". Takening apart and reassemble wouldn't be a specialist, like yourself, to line it up perfectly. 👍Love your videos!! 😃😎
Keyways must have play in them in order to be assembled, so, as well as adding more manufacturing steps and a stress riser that could initiate fatigue cracking in the shaft and gear, doing this will not locate the gears on the shafts as precisely as a press fit. It also add radial movement to the gears, which will likely create noise through imbalance as the gears will naturally tend to run off centre with the shafts, which can't happen on press fitted parts.
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this!
PLEASE HELP!
As a machinist, I would say that the use of aluminum in this application is insufficient. I would be very worried about the aluminum spinning on the shaft causing catastrophic failure. That being said, your ingenuity and execution was spot on. You did a really good job. I dont know what cost is associated with producing these lobes, but im assuming less that 50$ for material and machine run time. Take a lobe and a straight cut gear to a tool grinding shop they can precision grind id and profile with tighter tolerances and better press fit. Very awesome video! And the shop cam select the correct material based on hardness of straight gear.
I'm surprised it was worth it to go with aluminum rather than a more thermally stable metal like steel. With steel couldn't you tighten up the clearance between the gears more because they will expand less, ending up with a more efficient pump?
Imagine taking a shot every time he says “these gears”😂
Alcohol poisoning within the first minute
Death within the 2 minutes
XD
Now I'm only looking for "these gears", thanks to you.
This is a great idea, but what's the thermal expansion effects going to be like? Aluminum has about double the coefficient of linear thermal expansion compared to steel, so when submersed with hot oil for hours, could the new gears begin to slip from their press fit on the shaft and hit each other?
Be careful with that extra amount of flow, I've seen pump gears explode due to the resistance of the oil at high rpm. Awesome work :)
This concept intrigues me. I know oil pressure is largely formed by the bearings, so is there any way to keep the oil pressure down after you beef up the pump? Do more/bigger oil passages do anything about oil pressure? What if you simply used a smaller pan and reduced the amount of oil in the system? Less oil would mean the pump will have periods during which it pushes less or no oil, so I'd guess that's actually a lubrication concern for the pump and the bearings, not to mention a concern for the longevity of the oil between changes. Thoughts?
@@youmakeitwhatitis Higher pressure means the film layer in the bearings can support more load. Not a bad thing at all. The only cost is power to provide that pressure. Probably minuscule.
@@youmakeitwhatitis All pressure pumps have a bypass of some sort to control pressure; usually part of he pump but sometimes fitted in the main oil gallery. If you increase the flow of the pump significantly, you then need to increase the size of the bypass. However, since this is a scavenging stage, there should be no significant pressure.
I don't think that's what the OP had in mind though. I think he is talking about surface tension. The faster a solid strikes a fluid, the more that fluid behaves like a solid. Hit a fluid fast enough and it can well be "harder" than the solid that hit it. I can see how this property could be a problem in a scavenge pump at very high RPM.
He hasn't altered the pump or output performance of the drive pumps, only the transfer pump in stage one that's essentially a siphon from one sump to the other. Frankly the whole system is a little overdesigned, as an easier way is to simply have a larger sump and more oil (which is better for cooling) and then the active pickup is never starved for oil. Anyway, this modification will only affect how quickly the stage one pump transfers and dries the first sump and keeps the active second sump fed. As he states in the video, the face cut gears were much quieter when moving material, but the motor spends very little time in that condition, once the stage 1 moves all the available oil from that sump, they go dry/partially dry and whine loudly from then on. The active side pumps (that push oil pressure to feed the motor) weren't changed other than fixing the second set of gears to act as the drive gear for the second shaft. That should have negligible effect (if any) on the pump characteristics and performance of the active system
I think you underestimated the wear it is subjected to from picking up dirty oil from the sump. Bold move making it out of aluminium.
Lycoming aircraft engines used aluminum gears early on.. they had issues and changed them to steel. Interesting test he did here, but steel is better.
Well done! This is some refreshingly straight forward trial and error mechanical engineering. Keep up the good work!
Have you factored thermal expansion of aluminium in your design? If not you could have problems when engine oil gets hot - press fit could get loose because steel shaft expand less than aluminium gears and tolerances between gears could shrink too much.
Yes he did
Oh how I miss that noise. Each time I hear it I regret selling my old SL55....
I think of my first time I sat in a C55 Wagon....
If you plan on doing more of these you could make an installation fixture which both gears sit inside of in the correct orientation, center distance and axial offset offset so you can press fit both at the same time, that should remove any potential for them to be out of phase. It would basically just be a stepped piece of material with a close tolerance to the outside of each gear and two through-holes so you can press both to full depth in one operation.
The three lobe pump has been out there for a while and companies like Komatsu, CAT, Hitachi etc have been using them in their hydraulics. But you have shown a good application in Mercedes Benz engines to rid of the whinning noise. Maybe you could get in touch with Daimler Benz AG, their head office and show these improved results and who knows they might use this designs in their engines.
The only concern is the higher flow (so the pressure release valve needs adjusting) and using the softer aluminum for the lobes. The aluminum could wear out due to cavitation and friction from molecules of oil. Steel would be a better material. Finally, you can time the lobes perfectly and easily by using a jig to line them up while assembling. And if you have ideas that have not been patented before, register a patent or design and reap the benefits of your invention.
Just curious if this vast improvement in oil flow could cause over pressuring elsewhere in the system? Thanks for your talent and patience in creating this product and video.
That is a substantial display, the additional problem is the standard gears break down the long chain molecules that give viscosity, much faster than your design because you don't put the oil in "shear", a real problem with hot engines, lots of pressure, and there is no recovery when the molecular structure is broken, cooling doesn't restore viscosity, and it foams far faster than "sound oil, unscathed". Very much different. Thanks for the demonstration.
You could make a special press tool that holds both of the lobed gears in the proper orientation and allows both of them to be pressed on simultaneously. Also, since you used Aluminum, heating the lobed gears will make installing them much easier, they should FALL into place if they are heated, avoiding the need for pressing altogether. Combine heat and an installation jig and you'd have a relatively easy installation process.
It's a very tight fit. You can't expand aluminum that much without melting. Making a fixture might make it easier but because of the backlash in the gears it still won't be a 100%, unless the gears on the other side have a fixture as well
@@xfmotorsports What is the interference fit?
@@xfmotorsports You can add shims to either bias the lash to one side or center the gears to divide the lash, then install the lobed gears on center.
@@eformance I believe it was 2.2%. Aluminum expands around 1% max. Yeh shims could have solved it
@@eformancePLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this!
PLEASE HELP!
I wonder if the M111 engine has the same pump design, since mine sounds exactly the same on startup. I always thought it was the power steering pump
Remove the serpentine belt and start it for a few seconds. If the noise is still there then it's the oil pump.
Let us know, I had a m111 too and I always thought it was the supercharger..
Heaving a dot here, also got a M111 with this noise.
Same here, also got the M111 sc
Awesome video and its interesting how rotary style lobes (don't know what you actually call them) are coming back into fashion for water pumps / dry sumps etc. I learnt about them from my commercial rotary compressor only draw back from my understanding is tolerances play a huge part in them working efficiently or at all.
Keep it up i shall be back to watch more
Couple of points correct me if im wrong,
1 most of the whine should be coming from the supercharger
2 aluminium is not going to last those gears need to be steel, thermal expansion etc etc
3 when you spun up the old pump the drill was at a moderate speed then there was a noticeable speed increase when you spun up the new pump you can see this if you focus on the clamps on the "flexy" shaft. so i would question the flow differance.
The idea is good and sound i think the pump gears just need to be steel or the oil could go full "twilight" on you
Hopefully the heads can drain the extra flow, I know that's an issue on the RB engines. Also, you should probably do a pressure test also, not just a flow test. As I'm sure you know, one does not always indicate the other.
The extra pressure is from the front sump to rear sump. The flow up to the engine is still from the two remaining old gears so no change there.
Wow that was an unsettling noise it made before the fix :D
pretty much every MB from the early 2000's have that noise. The loudest I have ever heards was always from the W203 C240's
not an unsettling noise when it's been there since day 1. Mechanical whining is.. different.
Be aware of aliminium doesn't hold too much with cavitation....for prototype serve the purpose but you should make them in steel and heat treat.....
When assemble try to heat the gear...it will much easy to put it in place and adjust..
Interesting gear design taken straight from multi lobed superchargers ( Rootes, Sprintex ) that have been around for many decades . The supercharger rotors are actually machined helical but theoretically they too , do not actually come into contact with each other except when there is an idler gear backlash and contact. The Sprintex units have coated rotors . Basically a pump is a pump whether hydrodynamic or aerodynamic . An improved version of this pump would incorporate the helix .
This is what happens if you never stop Formula SAE haha
Non-AMG M113's have this too! I've wondered my NA CLK500 made this "supercharger whine!" Good to know!
If you plan to do this mod many times I think it would be a good idea to fabricate a tool that slots into the first gear and the second shaft in order get the second gear in position.
PLEASE HELP!!! Can you help me with putting my m113k oil pump back together? My car 8 the serpentine belt so I have the oil pump apart and noticed the stars and Dot's on the teeth of the oil pump gears but I do not know how they realign.... Can you please help me with this!
PLEASE HELP!
I don’t mind the noise, as long as it doesnt fail and its solid😁
Awesome work! I always thought that whine on a lot of cars was a worn hydraulic power steering pump! Interesting to know it’s actually the oil pump.
it is similar to root blower. to reduce the noise use helical gear instead of spur gear the pair you're using, but assembling with helical gear is more tricky
Double the lobes.... and 6:50 that gap is to decrease wear and if you know how surface tension works..... The oil in that gap develops a sheet around the sprocket/lobe
Props on thinking outside the box but a little food for thought, most aftermarket oil pump gears I've seen are made from heat treated chromoly. There must be a reason the oem doesn't use aluminum maybe from galling issues.
You should have just keyed the shafts and made a slot in those lobed gears and then just drop them in place. Wouldn't have required such precious press fitting and the assembly could have been disassembled later on.
My only worry here would be that there might be enough backlash in the gears that are synchronising the shafts in the pump to allow the lobed elements to contact each other when the engine overruns. Gear pump gears tend to be a pretty tight fit together to keep the pump efficient though, so hopefully not an issue until there's a lot of wear on it.
I know it's an up charge - but for consistency is there any way to make a tool for locating / pressing them in at the same time? (if you had a press). Knowing most people - selling something w/ such tight installation tolerances might get you more negative feedback than positive?
It would cost more to make the tool then for someone to ship their pump here and just get it installed. For small numbers it doesn't make sense
@@xfmotorsports Try to 3D print a case to hold the 2 gears in correct position; when the first gear in place; use the 3d printed holder to hold the 2nd gear in correct position then press in. it may have higher chance to success.
Man, you made my day. I own and drive a M272 with this whining noise for about 10 years now and was always wondering what it is. As I exchanged the timing chain and pulleys for some other reason 😎, I already suspected the oilpump and it‘s drive chain. As always: excellent job, nicely documented. Thank you very much!!
272 is a different engine, and uses a different pump. 272/273 doesn't suffer from this problem. Check your drive belt pulleys, AC compressor, or PS pump. Those are the main culprits for noise on that engine.
I am petty sure, that the reason for using the "noisy" gears was the result of extensive sound design.
Well done ! Also, as you said, it looks like a massively higher oilflow - tremendous!
thanks for the laugh material on that stock pump. what about using key instead of press fit for both ease of assembly and serviceability?. or key on one side and locking screw on another side for adjustability?
Legitstreetcars would love this
Gear pump.
The gears will give a higher pressure vs the lobes.
Have you compared oil pressures once assembled in engine while running it?
After pondering this for a little while I realized one very large flaw in the testing. The stock gears being flat cut have a significant amount more resistance to turn than your new design. Which is great, especially for noise. However because you're only using a maximum canadian tire drill, you can see the clamps are spinning at different rates between the new and old design. So even though it appears the new design flows more, it's because the drill is spinning at a higher RPM due to less resistance. The drill does not have the required torque or control to spin both pumps at the exact same RPM to test the flow difference, even just visually.
Very interesting! Great video.
After a almost 24 minute video, awesome results.. but why the heck didn’t you incorporate a finalized ending result with this pump inside one of the two vehicles at the beginning of the video? Or was there still the “Mercedes whine”? I’m sad to not see the pump put into one of these cars..
I just got my E55 back together last week because of a cracked oil pan. Replaced the O-rings on the pump too, wish this came a week earlier....
Where the o rings hard and brittle?
I always thought the noise was the power steering pump 🤣🤣🤣
I was wondering where your videos went! I was just thinking the other day I hadn't seen any updates about the car, this is just as cool!
The gears aren't press fit, they're most likely heat shrunk on. Warm up the gears in an oven before sliding them over.
Throw the shaft in the freezer and it should slid in.
If they were heat shrunk on, he wouldn't get them off with that gear puller and that little wrench. And "heart shrink" is ambiguous, as you can hear ANY part to get it on. He could have heated his new aluminum gear up with a heat gun and put it on. Would that make it a great shrink installation just because he heated it? All that matters is the degree of interference. A part that has enough interference, where you need to heat it to install it, is going to have so much cleaning force that he wouldn't get it if with that gear puller.
@@xenonram so you saw the same video everyone else saw, or something else? He's using aluminum gears on a steel shaft. Ie, pressing aluminum gears onto something that's harder will wallow out the hole. This isn't steel on steel.
Who wants to be the guinea pig and risk his engine for these gears?
theres no risk
These will expand with heat, the outcome will be oil starvation.
There's your no risk conclusion!
@@josep.3364 It is a scavenge pump, not the main oil pump
oh, and the main pump gets its oil from ?
@@josep.3364 The sump
I bet if you made the "drive" gears helical, even something small like 10 degrees you would go even further in reducing the noise. Just have to consider side load at that point. Just a thought if you wanted to take it further.
I absolutely obsess over this guy's content because of my even-worse obsession of M113 powered AMG cars, but I have to wonder if sacrificing the many thousands spent by MB's R&D to manufacture an oil pump that has proven to last forever but makes an audible whine when cold should be replaced by something completely new and custom just for the sake of getting rid of the whine.
I'm concerned that the aluminium gears won't last, they will wear and put debris into your oil. Also the thermal expansion could loosen then off the shaft. I'd be tempted to remake these in hardened steel.
Great. I love it when somebody fixes German engineering
Is it a fix, though? Quiet operation is one thing but what about the oil pressure and volume push though that pump?
So, is the speed difference we see in the input shaft due to the added resistance from the old gear's friction fitting? If actually spun at the same speed is the flow actually that much higher? I would think the volume of oil pumped would be equal to the engagement area of the teeth times the number of teeth. Without the exact numbers it's hard to say, but it looks as if there is less 'total tooth volume' per rotation on the new design which would equate to less oil pumped per turn. When spun by an engine that won't notice the torque difference needed and that is set to maintain a given RPM in any case, I have a feeling the flow rate is actually lower on the new set of gears.
The 3 lobe has been around for a very long time. Your taking credit for this ??? WOW !
So you thinking about a complete package switch out and a customer ships a core and you assemble all? Charge a core return? I have a sl55 and would have interest to do this as long as I had to only put the complete pump in. Great video. Great content!
i wonder how much oil pressure it can makes, and how it compares to the original pump
Interesting project, however, you still have TWO steel spur gear pumps in that assembly which continue to make noise. Gear pumps are noisier because the gears have to make contact to transfer power from one gear to another, your lobe pump can not work independently, it has to rely on external gears to work, and those gears will always generate noise, so it is kind of defeating the purpose, not to mention it makes the overall pump bigger and more costly, maybe that's why lobe pumps are never used in engines lubrication systems
Drinking game!! Pound a beer for every random "yeah" thrown in.
Or these gears
I used to love that pump whine when I had my 55K way back in the day. lol
Mercedes: unification downgrade
XF: de-unification upgrade
Its cool that you tried and did it man.... but I would have just bought a drysump pump there are so many good vendors out there. Its just alot of effort and time vs relatively inexpensive pumps considering.
Drill a Dimple in the side of the gear lobes for better sealing and lubrication.
Also flow doesn’t indicate pressure .so check that .
Explain more about the dimple please
This is only the scavenging side so pressure isnt as important as flow rate, the other stages provide the pressure
@@noncog1
The void it creates collects oil that lubricates and seals it better .
Check the old guys doing Chevrolet pumps .
Can you say PATENTS!!
Love your channel and I still plan on bringing my CDI to you for upgrades.
WE NEEED A "these gears" counter
Maybe machine index marks on each lobe and each indentation that shows the center of them? Or idea 2: Maybe like a sheet of plastic that needs to fit through them to confirm the gap?
The thermal expansion coefficient of aluminum is a good bit higher than steel after some time the aluminum gears will loosen and most likely touch then destroy each other, A better material would have been copper which has a close expansion coefficient to steel but ultimately the final gear should have been steel, especially given how time consuming the assembly is ur not going to want to keep replaying them and dealing with shards of aluminum in ur oil
Forgot to mention still a fantastic video!! U did a great job also it probly would have been worth it to 3D print an alignment guide
Interesting but with litigation being what it is, a long term testing regime might prove cost effective.
You might consider hard anodising to reduce cavitation damage, or better consider steel. The idea seems good but possibly under developed.
Wow! Awesome work! Do the regular 5.0 engines use the same pump? All our E500’s make a similar noise and it’s always drove me nuts.
Yes. Its the same scavenging section.
Biggest issue I had with my C55 was the pump noise at startup.
Use a reamer to control the i.d of the gear. A Jig is the only way to clock those gears. Benz power steering pumps are noisy a.f too.
Pls do an video on the E55 ASL project cost for all the parts and future plans
When the engine is hot, won’t the aluminium expand more than the steel shaft?
There must be a reason why the original gears ate steel.
Brinelling is the main reason why OEMs don't use less expensive aluminum for oil pump gears.
Wear. But hey, it works for a youtube video...
really curious about how the aluminum gears hold up. im not sure wear is the only concern, my first thought was cavitation damaging the peaks and valleys of the gears (where cavitation is most likely to occur)
i wonder what a set looks like after a few thousand miles.
The straight gears have the noise at startup only and then quiet down quite quickly. Is this because the pump is saturated with oil or all the oil has been scavenged from the front sump?
And to be clear this 'new' gear chamber just moves oil from the front sump to the back right?
It is a very annoying noise tbh - and having it quieter is much preferred - its just a bit difficult to pick up the different noises generated with the impact gun in the background! Do the other straight gears also make this noise? Why is the front gear the loudest?
Personally I would have made the gears out of steel - but I assume this is just a case of changing the base stock during manufacture? Press fitting ally onto steel gets me a bit worried about the ally fracturing over time - when under load for many hours and heat cycles especially given the very tight tolerances.
Suggestion for the gear alignment: Having some sort of fixture you machine like a thick piece of plexiglass or other cheap, rigid material that could be machined as an outside fixture to keep the gears rotated into their proper 'phase.' I say something cheap so you can ship it out to the customers with the gears.
AWESOME! I could not find an affordable oil pump for my w210. My engine is ok but my oil pump is shot . Previous owner threw a belt and kept driving. it sucked the front main seal into the timing cover- dumped all the oil and clogged the pickup tube. The motor runs fine but was making a horrendous noise from the oil pump.
Great video and explanation about the noise source. I thought this noise was coming from the chain. My W163 which has a M112 has little noise, but my w210 M111 has way more winning noise, and mostly on idle. Now I know ...
According to the number of gears set teeth in the oil pump, the oil pressure is different with the rpms of the oil pump gears and it’s teeth. For the performance engine, that design is good for avoiding oil starvation at high rpms in engine but not for normal every day driving engine, it will or can starve oil at engine idling.
Yes which is probably why he didn't change the pressure stage gears and left those stock. He only changed the gears that take oil from the front sump and dumps it into the rear sump.
@@mjcapp2174 yeah, man!
I would try to press them in simultaeniously while a 4ply strip of alufoil is in between them.
You will be getting problems with the hydraulic lifters due to the pulsation of the oil pressure.
Cavitation will also be a problem (Air in the Oil)
They know what they do at AMG.
Interesting video, do you know if the oil sump O-ring issue is also affecting S55 and CL55 due to equivalent O-ring used for collecting the oil? Can the oil pump chain tensioner be replaced from underneath without removing the engine from the car.
No, S55 and CL55 have a different pump. They don't use an o-ring to seal the collector. I believe the upper/lower pans and timing cover need to be removed to replace the oil pump guide and spring
@@xfmotorsports Super helpful, thank you very much. I am very impressed with your projects BTW, really cool with manual E55.
Awesome job, very complicated work to get it right.... are you worried about cavitation damaging the lobes over time? I’ve seen it damage steel gears over time, not sure how aluminum will hold up
Whoa, did you consider like a twin screw design where you have 2 different lobes that fit to each other? Or a slight helix to help compress from pan side to port side?
Hello, this has been tremendously informative and educational - I would REALLY hope you keep making videos with such detail.
I have several concerns about the pump, though:
It seems like you increased the flow that the pump creates per rotation. Since this is a dry sump this might not be a problem, but doesnt that increase the load on the shafts and consequently on the steel gears which are used to time the shaft?
Another problem which might result from this:
With the increased flow and and therefore lower pressure at the inlet of the scanvenging pump, i suspect there might be a higher chance of cavitation to occur at high rpm. Thankfully you made the lobes out of aluminium so it will be visible in no time if such a thing happens.
Great vid, though.
Would give the gears a twist similar to a roto/twin scroll style supercharger help with increasing oil pressure to?
Тест на то работает или нет новая шестерня? Думаю надо было проверить какое давление он создает и точно замерить производительность, а то столько работы и просто в тазу побулькали.
You don't think there could be a risk of the lobes or the gears moving over time and actually touching?
You are gonna mess with hydraulic film between parts with this flow rate . Try mixing high viscosity oil with previous grade oil. Or add good quality oil additives. This is must to compensate the effect of new oil flow rate.