TIMING CHAINS vs. BELTS - Differences, Evolution, History and more

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  • Опубликовано: 15 авг 2020
  • What is up engine heads, today we will be taking a detailed look at timing belts and timing chains. We will compare one with the other and dive deep into the benefits and drawbacks of both of these critical engine components all while presenting objective facts on both of these.
    So what does a timing belt or a timing chain actually do? Well the key word here is "timing" and timing in this case refers to the relationship between your pistons and your camshafts and valves. For an engine to run properly this relationship must be constant and maintained at all times.
    Chains are more resistant to wear because of course metal resists wear better than rubber. But there's a catch. Metal resists wear well only when it's lubricated and this brings us to our first big difference between timing chains and belts. Belts run dry but chains are splash lubricated by the oil in your engine. This means that chains must be sealed away from the environment to prevent oil leaks. The easiest way to tell if your engine has a belt or chain is to look at the engine. If it has plastic covers on the front, it's likely running a timing belt, if it has a sealed metal cover than it's likely running a chain.
    Because they are more durable timing chains have much longer service intervals than belts, some chains don't even have service intervals. They last the life of the engine. Even if you don't use the engine at all, a belt should be replaced after 6-10 years, depending on the engine. This is because rubber naturally deteriorates and degrades with time. Timing belts are sensitive to oil and coolant spills, which can significantly shorten their life. High temperatures also contribute to increased rubber wear. A typical modern timing belt needs to be replaced every 60.000 - 100.000 miles. When timing chains do have service intervals, they are need to be replaced every 80.000 - 120.000 miles.
    While timing belts are generally the same and don't differ much in terms of their design, timing chains come in two main different types - the silent chain and the roller chain. Silent chains minimize the amount of noise created by chain and sprocket assembly.
    Silent chains are very common in engines and are loved by manufacturers because they are simple and cheap to manufacture. They are constructed from multiple links connected together by pins. The profile of the links fits the profile of the teeth of the sprocket and voila the chain turns the sprockets.
    On the other hand roller chains incorporate rollers instead of links. The sprocket teeth fits in between the rollers and the rollers roll on the teeth as the chain rotates the sprocket. This both reduces friction and helps spread loads more evenly which also reduces localized wear. Roller chains can be of a dual or single type and as you're probably guessing dual rollers are more durable but due the increased surface area they also create more friction.
    The drawback of roller chains is that they are noisier when compared to silent chains and that they are also more sensitive to debris and contaminants in engine oil.
    The first ever engine with a rubber toothed belt was racing car built by Bill Devin in the early 50s. It was a Frankenstein engine that used two Norton Manx cylinders on a Panhard crankcase and an overhead cam layout. The first ever mass produced car to feature a timing belt engine was the West German 1962 Glas 1004. In 1966 Fiat also introduced the first twin cam engine driven by a rubber toothed belt and in the same year the United States got their first belt driven engine in the form of Pontiac's overhead straight six engine.
    So does this mean that belts are the better choice and that you should choose and engine with a belt instead? No, it simply means that the demands put on today's engines have equalized belt and chain statistics and that some of the good reputation chains had doesn't apply anymore. The reality is that both engine drive systems are equally good provided you maintain your engine and replace components with quality ones when needed.
    What's more important than belt or chain is maintenance as well as research. Before buying a car with a certain engine, make sure to do your research well and get acquainted with the engine's weak spots so you know what too look out for inspecting the vehicle and can accurately predict realistic maintenance cost that best suit your budget, needs and preferences.
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Комментарии • 2,4 тыс.

  • @d4a
    @d4a  3 года назад +43

    Support d4a: driving-4-answers-shop.fourthwall.com/
    HKS Fine Tune Timing Belt: amzn.to/34rdU7m
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    • @sefutho
      @sefutho 3 года назад +1

      We've never had an engine where the sprocket is directly connected to the crankshaft via a gear?

    • @robertmorris6529
      @robertmorris6529 3 года назад +3

      @@sefutho GM produced 6 cylinders late 40's ( maybe earlier ) compressed fibre cam gear , used in Australian Holden engines until end of Chev based , " Grey , Red , Blue , Black " engines .

    • @sefutho
      @sefutho 3 года назад +1

      @@robertmorris6529 OK thanks you so much Sir

    • @Michal_Sobierajski
      @Michal_Sobierajski 3 года назад

      You should talk about one of the longest engine belt in ES9A engine 😂

    • @bicboi1930
      @bicboi1930 2 года назад +2

      Timing ropes are OP

  • @BensHacks
    @BensHacks 3 года назад +3006

    A belt will last the whole engine life. The engine life simply ends, when the belt fails 😜

    • @d4a
      @d4a  3 года назад +231

      Lol!

    • @jacobhill3695
      @jacobhill3695 3 года назад +83

      All 4g63 engine owners are quick reminded or informed of this failure

    • @kchristensen6283
      @kchristensen6283 3 года назад +89

      Pfffttt.... Toyota laughs at this....

    • @jamesflores9456
      @jamesflores9456 3 года назад +30

      Not on any Toyota

    • @StopTeoriomSpiskowym
      @StopTeoriomSpiskowym 3 года назад +34

      When chain loose in engine can make meet piston with valves. the long timing chain from the crankshaft to the camshaft in the cylinder head stretches much more easily. by adding to the wear of the slides and sprockets, such a chain can jump on and destroy the engine. manufacturers give large distances between chain replacements, but the tensions are defective chains loosen earlier

  • @justayoutuber1906
    @justayoutuber1906 Год назад +423

    We had an early Acura that had a belt snap long before the 60k change interval. It was insane how interested Acura/Honda was on the root cause analysis. The engine was totaled and was sent back to Japan. And the incident went way high up in Acura, we heard - like VP level. They knew who worked on the line, what day, etc. It was impressive. Anyway, got a new engine out of it. Been a chain fan ever since.

    • @martijnnieuwenhoff4474
      @martijnnieuwenhoff4474 Год назад +12

      Wow!

    • @clb_52
      @clb_52 Год назад +10

      The age of the belt is just as important as the mileage

    • @gabeishere4990
      @gabeishere4990 Год назад +3

      Well what happened to the guy? Did they fire him?

    • @hovnocuc4551
      @hovnocuc4551 Год назад +23

      It took probably a few thousands of broken engines and many disproven lies for VW to acknowledge there's an issue with timing chains in EA888 before they finally came up with fixed tensioner. Fun times.

    • @christopherjones512
      @christopherjones512 Год назад +1

      Chain's last way longer period

  • @javabean215
    @javabean215 3 года назад +218

    I used to work on a lot of VW TDIs. All of them were timing belts. I spoke with an engineer about why they went with belts, and the reply was that with 19:1 compression there's no room for error and chains can stretch, especially over a long time. The belt doesn't stretch nearly as much, and by following the VW prescribed timing belt change procedure you effectively re-zero the timing. The correct procedure has you lock the cam at TDC; loosen the bolts on the injector pump to lock it at TDC; then move the crank to TDC and lock it. That brought the engine back to factory fresh timing, and should be done every 100k miles (it was originally 60k miles, then moved to 80k, and finally 100k as the belts improved).
    Mechanics who were not familiar with this engine would do a "mark and pray" timing belt change where they'd mark positions of the belt on the cam, crank, and injector pump; then put corresponding marks on the old belt, then transfer the marks to the new belt; then they'd put the new belt on exactly like the old one came off. Over time you'd end up with engine damage if you did a couple of these in a row because of timing drift related to belt stretch that was never corrected.

    • @chegadorchegando5872
      @chegadorchegando5872 Год назад +19

      Comment full of Wisdom. Thank you

    • @jimmydesouza4375
      @jimmydesouza4375 Год назад +10

      How the fuck can a chain stretch more than a belt, assuming roughly equal cost and production quality?

    • @javabean215
      @javabean215 Год назад +16

      Over 400k or more miles the stretch of a chain would cause damage in a 19:1 engine. VW TDIs with that mileage are still quite common on the roads. Yes, they've had 4+ timing belt changes, but each one brought timing of the cam, crank, and injection pump back to "zero". Plus, the cost to replace a chain would be far more than the 4 timing belt changes.

    • @gyrdin
      @gyrdin Год назад +14

      @@javabean215 it just means that 4x+ timing belts will stretch less than one or two timing chains along the way. Belts are also cheaper to produce and more expensive to maintain, so it's just a good example of transferring costs to the end buyer. No offense.

    • @VEX350Z
      @VEX350Z Год назад +6

      Sorry m8, i belive 4 change of belt would be bigger cost than 1 change.of chain in same amount of kilometers.

  • @gnarly3327
    @gnarly3327 Год назад +224

    I'm an IT engineer but know nothing about cars. I recently bought a car to work on and your engineering take on automotive tech makes me understand the engine and I diagnosed every problem the car had and even improved some points. Thank you.

    • @gravemind6536
      @gravemind6536 Год назад +15

      If you can assemble and fix computers you'll be able to fix cars if you so choose. Lot of overlap and skillset similiarites between the two.

    • @averagedev7768
      @averagedev7768 Год назад +6

      @@gravemind6536 actually IT engenere is usually a software engere. But you still have the point

    • @JaredConnell
      @JaredConnell Год назад +10

      ​@@gravemind6536 assembling computers involves no more than a screwdriver. Going from that to working on a car is like saying you can be a chef because you can cook macaroni and cheese. Sure, after building a computer you will probably be able to change a taillight, but you're not gonna be able to rebuild an engine any time soon.

    • @ethanhawes4103
      @ethanhawes4103 Год назад +16

      @@JaredConnell That's not what they're talking about. Any one can turn a wrench. The overlap being referred to is understanding systems. If you can understand the underlying system that enables a computer to run, you can understand an engine. That's the hard part.

    • @whatdadogdoin7531
      @whatdadogdoin7531 Год назад +12

      Pcmasterrace when they find out their car is pre-built

  • @davidrobert2007
    @davidrobert2007 3 года назад +563

    Gear driven cams are the most reliable though.

    • @somerandoonline5852
      @somerandoonline5852 3 года назад +73

      I completely agree but im sure nobody is gonna be able to survive the noise the gears make against each other

    • @otm646
      @otm646 3 года назад +39

      Longevity and reliability are not the same thing. A timing belt or a chain motor is going to last just as long as gear driven motor assuming you actually do the maintenance.

    • @davidrobert2007
      @davidrobert2007 3 года назад +77

      @@somerandoonline5852 My motorcycle has straight cut gears driving the cams and the sound they make is no problem at all. I quite like it, it gives the engine more character and is maintenance free.

    • @davidrobert2007
      @davidrobert2007 3 года назад +43

      @@otm646 But the maintenance can sometimes be a problem, for instance a 12 year old Audi S5 4.2 v8 timing chain replacement will cost nearly as much money as the whole car is worth, so economically unworthwhile.

    • @renz1013
      @renz1013 3 года назад +10

      @@somerandoonline5852 yeah only people who like the cranky sounds of it would so I agree with ya

  • @Hunting_Party
    @Hunting_Party 3 года назад +566

    Imagine needing to time an engine. *laughs in rotary* *laughter slowly turning into sobbing*

    • @XStuntManiac
      @XStuntManiac 3 года назад +77

      *laughs in 2 stroke and cries while extincting*

    • @richardcaldwell6159
      @richardcaldwell6159 3 года назад +10

      Yeah, the sobbing makes sense. Tough being married to bi*** with irreconcilable heat loss, friction, and pressure limitations and loss issues.
      I feel4u, man

    • @JesusSaves86AB
      @JesusSaves86AB 3 года назад +21

      Don't forget to check your oil.

    • @DexMaster881
      @DexMaster881 3 года назад +13

      @@XStuntManiac Mhm.. imagine being a 2 stroke Diesel and complaining to Europeans about their emissions...

    • @codyblea3638
      @codyblea3638 3 года назад +6

      @@XStuntManiac chainsaws bro. The new STIHL 462 is a beast of power at a wieght that scares me. At like 2/3 max rev, the saw climbs in the air. The tip goes up significantly.

  • @shawn576
    @shawn576 2 года назад +4

    I'm amazed someone could make a 20 minute video about this and none of the video is filler nonsense.

  • @borayurt66
    @borayurt66 Год назад +60

    Belts have improved over time too, more advanced rubber compounds combined with Kevlar reinforcement made them quite durable compared to old versions.

    • @techartic4771
      @techartic4771 Год назад +1

      why fix something thats not broken?

    • @tomdoppio
      @tomdoppio Год назад

      I had a mercedes 2014 e200 coupe (second hand) with a timing chain that failed at 60,000 kms. and camshaft adjuster broken (cracked so they had to flush the engine 5 times) and fuel injectors clogged. costing me $10,000 to repair... was i scammed? i never wanted a german car ever again after that.

    • @bigboi8426
      @bigboi8426 Год назад +6

      @@tomdoppio if you took it to a dealership then ya😂

    • @jakebatty530
      @jakebatty530 Год назад +1

      And then there's wet belts, that run in oil, and as the oil accumulates crap from the engine it degrades the belt rapidly, especially if you don't use the exact oil spec, otherwise you'll be doing a belt every 30k miles or 3 years if you dont want it to snap

    • @a64738
      @a64738 Год назад +1

      Timing belt is the worst... NEVER EVER BUY A CAR THAT HAS TIMING BELT !!! I have had timing belt snap on one of my cars 3 times on my first car a 1,6l Opel diesel. Next car was a brand new Opel 1,6l petrol car that I changed the belt on after only 25.000km and 1,5 years instead of the recomended 60.000km / 4 years, the belt was almost shredded and has skipped 2 teeth. But the worst was on a 2001 Mazda 626 diesel 16valve where the timing belt snapped and destroyed the engine and the car was a wreck after that and got condemed... On all the cars all services was followed with regular checks and cange of timing belt. ... ... . ..

  • @abhishekchaudhary9542
    @abhishekchaudhary9542 3 года назад +143

    Never knew that there were two different kinds of timing chains. Great work.

    • @christophermarshall5765
      @christophermarshall5765 3 года назад +4

      I've known about both types of timing chains for a very long time. The "Morse" type chain isn't used as much these days, in favour of the roller chains.

    • @chippyjohn1
      @chippyjohn1 11 месяцев назад +1

      There are actually more than 2.

    • @chippyjohn1
      @chippyjohn1 11 месяцев назад

      @@christophermarshall5765 He did not even mention Morse, he is just calling all the various 'silent' chains as the same.

    • @christophermarshall5765
      @christophermarshall5765 11 месяцев назад

      @@chippyjohn1 the flat chains in car engines are properly called Morse chains after the designer of them.

    • @christophermarshall5765
      @christophermarshall5765 11 месяцев назад

      @@chippyjohn1 the flat chains in car engines are properly called Morse chains after the designer of them.

  • @bustahbuds
    @bustahbuds 3 года назад +82

    I just watched a 20 minute video about timing chains/belts and was on the edge of my seat the whole time! Great job!

    • @martinbeijer2385
      @martinbeijer2385 2 года назад +1

      me too, you are making videos with some heavy information really effortless to watch. Didn't expect this when i logged in to youtube today :)

    • @Jdalio5
      @Jdalio5 Год назад +5

      Me too...but on the edge of a toilet at work

  • @ConquerDriving
    @ConquerDriving 3 года назад +96

    Totally agree with you, in one of my own videos I also mentioned that belts and chains are equal, best to research the particular engine you are about to buy.

  • @waltwimer2551
    @waltwimer2551 3 года назад +43

    Another excellent video! I love the fact that I already know a decent amount about these topics, but I *still* always learn new things from your videos, and they are always enjoyable / entertaining! You have a gift, sir!

  • @williamstewart3469
    @williamstewart3469 3 года назад +16

    Someone in the comments called it, this gentlemans hair style keeps getting better. But on a serious note, another insightful and informative video Sir. Fast becoming a legend man.

  • @JoNoBaRr92
    @JoNoBaRr92 3 года назад +71

    Just found your channel tonight. Watched Boost School up to date and iron block vs aluminium plus more. Absolutely hooked! Great presentation and extremely clear explanations of any topic you cover! Love it!

  • @MegaNardman
    @MegaNardman 2 года назад +15

    Great breakdown of the subject. It all does come down to the application. There are a couple other considerations which make belts, in general, more preferential to me from a maintenance perspective:
    1. While chains are made of metal and theoretically will wear better, they often depend on chain guides or other integral parts which are made of plastic.
    2. Replacing a belt is a planned maintenance piece, replacing a "lifetime" chain that's failed is often an engine-out procedure.
    3. Belt replacement is a great time to replace belt tensioners and the water pump prophylactically ahead of when they would become a problem.
    None of this would steer me away from a reliable chain-timed engine, but it does factor in to the practical livability of the two timing systems.

    • @timesthree5757
      @timesthree5757 2 года назад +1

      In my experience as a mechanic they are both just as hard.

  • @SE45CX
    @SE45CX 2 года назад +12

    What I like in your presentation style is the continues evaluation of pros vs cons on every design aspect.

  • @El_Chompo
    @El_Chompo 3 года назад +301

    I sure hope free valve becomes a thing. There are such incredible amounts of improvements available to engines through unlimited valve timing and duration. It would really be a whole new level of engines. Everybody gets so exited about Vtec. Freevalve is like Vtec times a thousand.

    • @BigUriel
      @BigUriel 3 года назад +29

      Other continously variable valve lift and timing systems already exist in production today. Free valve does not add much over those except for high rpm/high boost applications which might benefit from the square valve profile, and maybe an easier way to implement cylinder deactivation.

    • @ghoulbuster1
      @ghoulbuster1 3 года назад +9

      Can't wait for free-valve, such a huge technology leap.

    • @wallyhare8616
      @wallyhare8616 3 года назад +27

      The concept has been out for almost 10 years or so. I doubt they do it full scale before the oems switch to all electric ⚡️

    • @hdrenginedevelopment7507
      @hdrenginedevelopment7507 3 года назад +36

      Never buy the first generation of anything. It's a cool idea, but longetivity/reliability and especially tuneability is critical to me. That's going to be a painfull repair bill if the actuators prove to be Russian roulette after 100k miles, which is when most of us enthusiasts are inheriting other people's problems, because we can't afford or don't want to pay those kinds of new car depreciations. One of the reasons stuff like Hondas are so popular...they weren't terribly expensive to begin with, 100k miles is nothing if they were reasonably maintained and they are typically indestructible even beyond that, and they are nearly infinitely modifiable.

    • @El_Chompo
      @El_Chompo 3 года назад +2

      @@hdrenginedevelopment7507 but.... infinite vtec bro

  • @dzonijohnny5718
    @dzonijohnny5718 3 года назад +9

    Complete underrated channel compared to big channels on youtube.
    1. The content is excellent and informative.
    2. His english is really clear and easy to understand. That is a advance for foreigner english speakers because they do not have to learn first to speak clear like a narrator without dialect or peculiarities.

  • @immanuelkouldnt7601
    @immanuelkouldnt7601 2 года назад +10

    I enjoyed 100% of your videos so far, they are very clear and well made. Seriously, keep up the good work!

  • @jaredkennedy6576
    @jaredkennedy6576 2 года назад +30

    Timing gears are a great option on pushrod engines, but can be noisy as well. When I upgraded my old Ford 300-6 to steel gears it sounded like it had a blower, and I'm sure if I could hear anything over my 7.3 it'd be the timing gears.
    I have had a pushrod engine with a timing belt, though. Strangest thing ever.

    • @huey-fan8335
      @huey-fan8335 Год назад +3

      Well, the VW 2.5 I5 and 5.0 V10 TDIs have timing gears as well, they have the nickname "children's rattle" for a reason.... 😂

    • @kimrowoon2474
      @kimrowoon2474 11 месяцев назад +1

      No problem On The noise atleast it can last decades

    • @johannriedlberger4390
      @johannriedlberger4390 7 месяцев назад +1

      The WW2 Jeep had a gear driven camshaft. The gear on the crankshaft is steel but the one at the camshaft is plastic. Surprisingly the steel gear wears faster.

    • @octosquatch.
      @octosquatch. 3 месяца назад

      The microscopic grit in the oil gets impregnated in the plastic and turns it into very fine sandpaper.​@@johannriedlberger4390

  • @scunnerdarkly4929
    @scunnerdarkly4929 3 года назад +43

    Entertaining and informative as always, one of the most watchable auto channels out there 👍

  • @adrianolacerda3410
    @adrianolacerda3410 3 года назад +307

    Two strokes be like: aye mate wtf is timing

    • @jamest5149
      @jamest5149 3 года назад +19

      Port timing? Power valve timing, ignition timing 🧐

    • @ericspecullaas2841
      @ericspecullaas2841 3 года назад +2

      More timing = more better

    • @denimory
      @denimory 3 года назад +6

      @@jamest5149 port timing? ports are there u cant move them,its not like ur ports will move when something brakes,they are just holes in cilinder
      thers only ignition timing and power valve and not every 2 stroke has power valve

    • @midwestmotorbikes2696
      @midwestmotorbikes2696 3 года назад +1

      Uniflow scavenging?????

    • @antievilnonane9606
      @antievilnonane9606 3 года назад

      What if to do JZ engine with chain?

  • @brentsnocomgaming7813
    @brentsnocomgaming7813 Год назад +10

    Surprised you didn't mention timing chain guide failure, for example the N52 is often recommended a 100k mile service life for the chain assembly, because the chain guides are made of plastic and can shatter.

  • @lightintheart
    @lightintheart 2 года назад +1

    Great job! You were so informative on both sides. You articulated this entire topic so well! I enjoyed this video. Thank you for letting me nerd out with you!

  • @joczo97
    @joczo97 3 года назад +121

    Those old Mercedes double roller chain engines,made until the late 90's can literally pass 1million km with the original timing chain,sprockets,etc.

    • @AuGold808
      @AuGold808 3 года назад +28

      That's why they had to do away w that shit lickity split

    • @hansgerd8069
      @hansgerd8069 3 года назад +2

      M112 ftw

    • @declannorton2023
      @declannorton2023 3 года назад +4

      *grins in OM606*

    • @leneanderthalien
      @leneanderthalien 3 года назад +3

      yes but only on OLD mercedes...

    • @Alexander_l322
      @Alexander_l322 3 года назад +17

      @@AuGold808 no money in reliable engines that never die. Can’t sell new parts and cars if they still allow older cars to run around being bullet proof.

  • @DexMaster881
    @DexMaster881 3 года назад +109

    K20: "Whats up with him?"
    _looking at m47_
    2JZ: " IDK man he just snapped..."
    OM606(@450): _laughing in 2.5bar boost_

    • @JOutterbridge
      @JOutterbridge 3 года назад +6

      Luckily my 2JZGTE belt snapping doesn't hurt the engine. Unless it's the JDM interference one, I'd hate that cost.....

    • @th3thin9
      @th3thin9 3 года назад +13

      OM606: *laughing in 2.5 bar boost @6500 rpm*

    • @chasp_0784
      @chasp_0784 3 года назад +1

      Nitro yep they don’t make them like that any more, 651 is an absolute dog

    • @RST-R-MODS
      @RST-R-MODS 3 года назад +8

      @@th3thin9 ,OM601 laughing at 2 million kms whitout any issue :D, OM6XX engines are the bests diesel ones :)

    • @th3thin9
      @th3thin9 3 года назад +6

      @@RST-R-MODS All mercedes Indirect Injection Diesels are bulletproof and extremely awesome!

  • @ag135i
    @ag135i 3 года назад +6

    Your explanations are one of the best on RUclips.

  • @izwanshaari9854
    @izwanshaari9854 Год назад +4

    All my previous cars use timing belt. Never suffered premature belt failure in any of them. My current car uses timing chain. Gotta confess it's nice for once not having to count miles until the next belt change. I'm not against timing belt but I would like it if manufacturers made changing the belts easier. Some of my previous cars can be daunting.

  • @Eduardo_Espinoza
    @Eduardo_Espinoza 3 года назад +96

    I learned more here than Engineering Explained 😀👍

    • @Eduardo_Espinoza
      @Eduardo_Espinoza 3 года назад +2

      @James Fox 100% still learned more here ;)

    • @lordjaashin
      @lordjaashin 3 года назад +13

      engineering explained has very dull method of explaining.

    • @creator4413
      @creator4413 3 года назад +7

      Can't pay attention to him knowing he is a shill

    • @NovaScotiaKevin
      @NovaScotiaKevin 3 года назад +1

      @@creator4413 Engineering Explained guy needs a hair cut. Badly.

    • @jozefm3044
      @jozefm3044 3 года назад +4

      Me too, no hate to Engin. expl. but I think he explains things more generally. Not specific as this guy. If somebody doesn´t know anything about cars I would probably point him to Engineering explained, and when he/she have basic knowledge of how things work, I would reccomend this guy

  • @flokithecat4819
    @flokithecat4819 3 года назад +1

    Just wanted to say thank you for all your videos. Your videos the way you explain things seem to make me understand infpmation so easily. Appreciate all your hard work.

  • @pembawangchuk5429
    @pembawangchuk5429 2 года назад

    your videos really deserve a combo award...keep updating us.thank you..

  • @bobgreene2892
    @bobgreene2892 3 года назад +5

    Outstanding-- a complex topic, clearly explained, with excellent graphics. I subscribed.

  • @douglasbell3344
    @douglasbell3344 3 года назад +5

    Great video, thanks. My Twincam Lotus has (single) chain driven cams (2 1/2 actually). One chain change in 50 years. Still outstanding performance! :)

  • @beni22sof
    @beni22sof 3 года назад +1

    This was awesome. Good quality information, history, everything. Good job!

  • @AliAlhussaini
    @AliAlhussaini Год назад +3

    When the belt is sus af, the piston and valves will have an emergency meeting

  • @Snowbag1998
    @Snowbag1998 3 года назад +3

    Great explanation. you went into a lot of interesting details. Keep up the good work !

  • @matthiassturm8200
    @matthiassturm8200 3 года назад +4

    Highly appreciate your detailed explanation of the all connecting "heart" element of a car. Learnt a lot!

  • @C64CMDMAD
    @C64CMDMAD 3 года назад

    Awesome as always and very fair too, Love all the Technical stuff and always a fair comparison. Keep up the good work !!

  • @RichadTheLionHeat
    @RichadTheLionHeat 3 года назад +2

    Absolutely outstanding! Extremely informative, great training aids, your presentation is AAAAA! I diffidently learned a lot about the topic. I had to share with with many peoples. Again, absolutely Top Quality production! 👍🏻😉👍🏻😉

  • @ColtaineCrows
    @ColtaineCrows 3 года назад +31

    Timing gears FTW! Also I believe Ford and VAG have some engines now with "wet belts".

    • @ghostwrench2292
      @ghostwrench2292 3 года назад +5

      Yes. Scary. I like my belts dry!

    • @lucasf123
      @lucasf123 3 года назад +2

      That requires specific oil!!!
      GM 3 cylinder engines are also using that amazing technology.

    • @fastboatster
      @fastboatster 3 года назад +1

      Lol, ea888 comes to mind)

    • @johnchestnut5340
      @johnchestnut5340 3 года назад

      Timing gears fail. Ask an owner of a 1985 2.5 L Pontiac engine. No engine damage...just stranded wherever it fails.

    • @fedjadrndarski5606
      @fedjadrndarski5606 3 года назад +1

      @@fastboatster Actually new version of timinig chain and tensioner has no problems at all on EA888 engines... gen1/2. Gen3 engine doesn't suffer from timing chain tensioner and chain problems.

  • @oshitt1
    @oshitt1 3 года назад +24

    Best channel ever, becoming one of my favorites, great job 😁

  • @jaimegrullon1202
    @jaimegrullon1202 2 года назад

    Love your videos , thank you for explaining things in such an easy way .

  • @paulwharton1850
    @paulwharton1850 2 года назад +1

    Excellent ! A class ( as usual ) 😇
    Thank you for making your videos - I have learnt a lot.

  • @gsmecanica
    @gsmecanica 3 года назад +3

    Nice video mate! I agree with you that today, chain driven engines might be more expensive to maintain than belt ones.

  • @shatterthemirror8563
    @shatterthemirror8563 3 года назад +12

    Recently decided to change my crankshaft oil seal and didn't know about the crankshaft key needing to be aligned with the notch in the pulley. Soon I had a broken chain and a complete set of bent valves. Thought "might as well rebuild the engine." Since it has over 300k miles on it. Now it's all better and I know a lot more about engines too.

  • @jeffnickels6199
    @jeffnickels6199 2 года назад

    This is among my list of “best channels” on RUclips for learning. Every video is awesome👍

  • @shresthamall9460
    @shresthamall9460 Год назад

    My new favorite way to pass my leisure time is to watch your videos. Never have I learned so much anywhere else. Objective to the core, just the way I like it!!! Much love

  • @blackbirdpie217
    @blackbirdpie217 3 года назад +5

    Great video. Having been a professional tech for 22 years I've replaced a lot of timing belts- and a lot of timing chains. It always frustrated me when most people thought chains were always without exception, better. As you said, not always the case. Today the GM High Feature V6 has a problem with chain lubrication and is known for having timing chain problems. I've seen every kind of chain wear out due to poor lubrication, often too infrequent oil changes but none the less, a belt is immune to this. I could go on with many examples but for me I favor a belt that's not difficult to replace, and be sure to conduct this regular maintenance to stay on top of the game. And I always wondered why belts went from a typical change interval of 60K miles to 120K, you answered it! By the way in the 1950s Chevrolet inline 6 motors didn't have either, but a gear to gear design.

    • @michaelbenardo5695
      @michaelbenardo5695 2 года назад +1

      Gears is best. Chevy 6s stayed gear to gear all the way up to the mid 80s, when the Chevy Stovebolt was retired in favor of a 262 V6 that was a small block V8 with the two front cylinders lopped off.

    • @blackbirdpie217
      @blackbirdpie217 2 года назад

      @@michaelbenardo5695 Gears can only be used when the cam is very close to the crank, not any overhead cam design. This may be reliable but always means RPMs are limited or valve float occurs, and internal engine power consumption remains high.

    • @michaelbenardo5695
      @michaelbenardo5695 2 года назад

      @@blackbirdpie217 I wasn't talking about OHC engines. I care more about torque than screaming RPM. And yes you can use gears on OHC engines. You need a shaft between the crank and cam gears, with those gears being ring gears, like that of a differential ring gear. The Crosley, a little tin can if there every was one, had such an arrangement.

    • @TassieLorenzo
      @TassieLorenzo Год назад

      @@blackbirdpie217 "Gears can only be used when the cam is very close to the crank, not any overhead cam design" Sure they can, they're just complicated and expensive, no? 🙂 E.g., Formula One or most purpose designed DOHC racing engines tend to be gear driven, and there are a few DOHC gear-driven road engines: the 'humble' Audi V10 TDI engine as well as where you'd expect in exotic road cars like the Ferrari Enzo or exotic bikes like the Ducati Demosedici.

    • @blackbirdpie217
      @blackbirdpie217 Год назад +1

      @@TassieLorenzo I do agree, the cam right above the crank is what allows a gear to be used without any belted link like a chain or T-belt but overhead cam is of course distant from the crankshaft. I have envisioned some kind of bevel gear and vertical shaft setup like as is used in linking the lower and upper mechanisms of a sewing machine, but this would need to be quite robust, and yet may be unreliable. Now they're testing electronic valves instead of using cams altogether. Some think there's no point now that electric is becoming the new technology, but it's not dominating yet so you never know what new next thing might surprise us.

  • @maxcactus7
    @maxcactus7 3 года назад +6

    Another fantastic video clearly explaining things that all serious engine heads and car enthusiasts should know, but likely don't. I would appreciate a follow up video in the future regarding how to check for timing chain/belt wear, replacement intervals, etc. I know replacing a timing chain is best left to a very competent professional, but other than changing oil regularly, is there anything else an owner can do to ensure maximum reliability and longevity?

    • @JOutterbridge
      @JOutterbridge 3 года назад

      Timing chains can be measured for stretch but if they are hidden good luck. Belts on the other hand you can hear or see wear. Just look for cracks and odd discoloration

  • @wernertschan320
    @wernertschan320 Год назад

    I really enjoy your videos so much. Learning a lot. You are doing a magnificent job! Thank you!

  • @gardenvape4021
    @gardenvape4021 Год назад

    Great video, great video series! Like the way you give the facts straight with no bias. You know what you are talking about for sure. Thanks.

  • @Rondo2ooo
    @Rondo2ooo 2 года назад +3

    I always selected my cars if they were designed with lifelong timing chains. I don't like the belts. Just a personal thing.
    Edit: Phenomenal explanation, great video!

  • @michaelcherry666
    @michaelcherry666 3 года назад +9

    This has helped to improve my understanding of the timing systems. I would be interested in learning more about this "free valve" concept for engines.

  • @orionxingu1758
    @orionxingu1758 Год назад

    Simply brilliantly explained and described. Good to know all these criteria when making the choice.

  • @williamlongbottom5494
    @williamlongbottom5494 3 года назад +2

    You are a well informed and talented presenter. Thankyou

  • @Sihijuoma667
    @Sihijuoma667 3 года назад +12

    Ford 1.0 EcoBoost has timing belt running in oil. I just changed the belt of my Focus after 250tkm. Not cheap but 4-5 times more durable than BMW/Mini/Citroen/Peugeot THP engine timing chain..

    • @Alexander_l322
      @Alexander_l322 3 года назад +1

      It’s called a wet belt and they still snap.

    • @teme5529
      @teme5529 2 года назад

      Here is another example from Finland: My toyota celica t-sport 1.8 (4cyl 192 hp na) chain is designed to last about 400 000 km, in addition to metal matrix composite materials used in the engine block. Not many on the road! And manual of course :)

  • @felixbgc
    @felixbgc 3 года назад +14

    I will love an expansion around oiled timing belts. Ford has engines with this new type of belt with service intervals over 150k milles. Thank you for your enjoying explanations, cool style.

    • @timesthree5757
      @timesthree5757 2 года назад +2

      Cool if the engines actually lasted that long and were easy to repair.

    • @frantisek8978
      @frantisek8978 Год назад +1

      These engines with oil lubed timing belts and direct injection (Ford 1.0 ecoboost, Peugeot 1.2 Puretech...) are garbage if used in a specific way. If a vehicle is often run on a short ranges, when engine doesn't heat properly, they dilute oil with an gasoline, thanks to the direct injection. After while oil can have pretty high contentration of gasoline in it. Apart from obvious mechanical damage to the engine, thanks to the lower lubrication, it also causes timing belts to etch and corrode its surface, bits of rubber release from the belt to the oil and eventually might plug oil galleries or oil pump strainer. This is not an problem, if car is running high milleage and is properly warmed every time, but when used on short ranges, oil should be changed after no more than 10k Km and timing belt after 100k Km, but lot of people doesn't do this, because they don't know about it and using long intervals prescribed by manufacturer.
      Lets take Ford Fiesta 1.0 EB, its cheap car and most people who buy it use it in low mileage, short range mode. Old people who drive from home to shop to doctor and back to home. Few kilometers through city with a lot of stops. Engine never heat up to operating temperature. Timing belt change cost something around 1200 - 1500€, because whole engine have to be taken out of the car. The price is huge for a small and cheap car. And you have to do it every 100k Km.
      tl:dr direct injected, dry timing belt cars are garbage on cheap cars and don't buy them if you drive small distances.

    • @wiilkasanadka10
      @wiilkasanadka10 Год назад

      @@frantisek8978 I thought Ford improved their 1 little EB since the early days or is it still garbage?.. I knew the Purecrap 1.2 wasn't Any gd that's why I went with the 1.0 in the Peugeot 108.

    • @dreece2000
      @dreece2000 Год назад

      Because of the belt the engine is junk. I like everything else about the little 1.0 3 cyl. Engine. Also has a belt that drives the oil pump that will break and you don’t have enough time to turn the key off. Ask me how I know.

  • @adrielklein189
    @adrielklein189 2 года назад

    Dude, I love your content, thank you for teaching me so much stuff

  • @mikegehre570
    @mikegehre570 3 года назад

    Great video. You explained the topic so well I understand it more.👍

  • @flyonbyya
    @flyonbyya 3 года назад +18

    Don’t forget....#4
    Running low on oil

  • @PhilOsGarage
    @PhilOsGarage 3 года назад +3

    My 2009 2.0d volvo V50 has a 140,000 mile ten year interval. I had it changed at 10 years this January, but the mechanic commented that it still looked good. Doing a bit of digging it turns out that cases of timing belt failure on these cars are incredibly rare, even when people simply don't bother to change. Definitely more reliable than VW TFSI timing chains.

    • @ElectricSwordfish
      @ElectricSwordfish Год назад

      Same with Honda 6 cyls. Honda recommends every 100k miles, but most people that came through the dealer I worked at were too cheap to do it when it was actually do. Manufacturers severly underrate the life on belts to protect themselves.

  • @peterreber7671
    @peterreber7671 2 года назад

    Very well put together and yes, even entertaining. Thank you.

  • @boomerguy9935
    @boomerguy9935 2 года назад

    Excellent comparison because it brought in the history and evolution of both, chains and belts, over the past several decades. Thank you!!!!!!

  • @autosanctuary7613
    @autosanctuary7613 3 года назад +6

    You should do one about timing gears. Even if it only be used in a limited capacity.

  • @kevinkainzbauer267
    @kevinkainzbauer267 3 года назад +4

    Actually the BMW N47 Engine made up to 214hp from the factory, as some N47 engines found their way into the E9x BMW-Alpina D3. In which they made 200hp as the single turbo- and 214hp as the compound turbo setup.

  • @kennethmadsen6474
    @kennethmadsen6474 Год назад +1

    Thanks for the explanation and history lesson.
    I just had my timing belt changed 25.000 km / 1 year ahead of schedule, because the engine warning light had come on (because of timing mismatch). 16 teeth had come of the belt. The mechanic said it was very lucky that the engine survived this with no harm.

  • @surfside75
    @surfside75 Год назад

    Love it! Been with you from the beginning. Nice to see you grow.

  • @chrislatchem1854
    @chrislatchem1854 Год назад +11

    Enjoyed it! Historically might mention geared driven cams, and even desmodromic valve timing on bikes...

    • @TheDrAkira
      @TheDrAkira Год назад

      Good to know thar there are people out there that still remember timing gears and also know desmo valve systems.

  • @L-Noble.YT_Hi.Res-Soundminds
    @L-Noble.YT_Hi.Res-Soundminds 3 года назад +10

    Thank you, you go slow and explain everything in detail so well that it's a pleasure to follow you and actually learn and understand.

  • @mzungusi
    @mzungusi Год назад

    You are the only RUclipsr who can make a video about Timing Belts/Chains and make it this entertaining.

  • @chriss6154
    @chriss6154 Год назад +1

    Great info. Thanks bro. Love all ur vids

  • @anvilsvs
    @anvilsvs Год назад +5

    Perhaps the most important reason for return to chains is variable timing using hydraulic adjusters. Which aren't very compatible with open dry belts.

    • @pontiacg445
      @pontiacg445 Год назад

      My 2002 miata disagrees. Usually cam phasers, which I assume you mean by hydraulic adjusters, need to be pressurized or drained in a controlled manner so they don't just dump oil everywhere. Anything going into the hydraulic adjuster comes from the solenoid, and anything leaving the adjuster also needs to go through the solenoid.
      There are more examples, too. I've done belts on volvos with VVT, same as my miata. Subies, they have VVT and belts. My 07 OBXT has AVCS, which is VVT on a belt. Of course it's exploded because it's a turbo subie, but that's unrelated.
      So I also disagree, variable valve timing has absolutely nothing to do with it. I don't even know of any leakage issues from any of those VVT setups, hell of a lot less than I know of chain driven water pumps leaking into the pan, costing several grand to fix...
      Volvo did eat the serp belt which found it's way behind the crank pulley and eventually jumped timing, didn't eat the valves though. Someone got lucky!

    • @anvilsvs
      @anvilsvs Год назад

      @@pontiacg445 You are correct as long as there's not even the tiniest leak from the phaser. Or the phaser is internal while the belt is external. Withe chains the sprocket is usually mounted on the exterior of the phaser itself which can shorten the engine just a little bit. And the chain will be narrower than a belt. That's not normally an issue with a longitudinal mount such as the Miata, but can be with a transverse mount.

    • @pontiacg445
      @pontiacg445 Год назад

      @@anvilsvs The phaser does leak, anything that leaks goes into the sealed front chamber with the cam bolt. The cam bolt is drilled through, anything that leaks makes it's way back to the sump via this route. As I said earlier, none of these systems are known for leaking oil. It doesn't happen often at all.
      Cam hydro phasers need surface area to work, the imbalance of pressure on a given surface area is how they work. Any of them you see, they are as wide as a belt. The chain takes up maybe 1/8 of the depth of the phaser. Size has nothing to do with it. As an example, volvo found it possible to stuff a transverse inline 5 with a belt into pretty much everything they made. They even fit transverse I6 with dual turbos, dual VVT and a timing belt. PITA, those cars...
      So, once again, VVT has absolutely nothing to do with the move towards chains.

    • @anvilsvs
      @anvilsvs Год назад

      @@pontiacg445 I really liked the Volvo transverse I6 design. Driving the transmission from the center of the crank eliminates one major problem with I6s, torsional vibration. More manufacturers should have done this.

  • @projectyuma7456
    @projectyuma7456 3 года назад +4

    Now ford star using the wet timingbelt and belt in oil drives. I will subscribe to your channel because i learn alot. Hope i can watch your explanation about the wet timing belt.

  • @constillustrus
    @constillustrus 3 года назад +2

    I looove your video’s. I am a newbie petrolhead. And I like what you teach a lot. So educational!

  • @cliffweinan3907
    @cliffweinan3907 Год назад +1

    Thanks for great analysis of both timing parts. I use to envy long lasting no maintenance OHV chains, then studied chain stretch problems when used with OHC. Ever use a chain saw? The chain bar has to be adjusted for chain stretch. Changed my mind about timing belts. Yes belts require maintenance, but at 100k it's probably a good time to replace belt tensioner and water pump. Just find an engine that is non interference and no worries about a broke belt causing valve
    damage. You don't want a timing chain to run a water pump because if water pump seal leaks, it goings into the chain lubricating oil !

  • @poptartmcjelly7054
    @poptartmcjelly7054 3 года назад +9

    I own a SAAB and the chain in the engine (B204) is a lifetime part, provided you change the oil regularly.

  • @JohnDoe-qb6yh
    @JohnDoe-qb6yh 3 года назад +5

    you should do a video about the fsi/ TFSI engines chain problems. They have both timing chain and.timing belt

  • @AlanChatham
    @AlanChatham 3 года назад

    These videos are super informative and fun! Thanks!

  • @MG-vo7is
    @MG-vo7is Год назад

    excellent info and enjoyable presentation. thank you.

  • @energymc22
    @energymc22 3 года назад +6

    17:50 my BMW B47 engine has a 19000 mile interval under ideal running conditions. I run 90% on the highway so ideal conditions according to the condition based servicing but do replace the oil at 10 to 12000 miles regardless

    • @bradcomis1066
      @bradcomis1066 3 года назад +1

      Wow, that is a pretty incredible service interval. You are definitely wise to shorten that interval. I think BMW stated at some point that their long service interval is part of a "commitment to reducing pollution." To me it seems like increasing the number of prematurely destroyed engines would have quite a large impact on their environmental footprint versus having to recycle more used oil.

    • @ricky-sanchez
      @ricky-sanchez 3 года назад +1

      @@bradcomis1066 Play on words. BMW was committed to reducing pollution by making it so that your car fails from a bogus factory oil change interval, and you go out and buy a new one. This keeps old polluting bmws off the road.😁

  • @cerseonbrassmann5222
    @cerseonbrassmann5222 3 года назад +3

    Cheers!
    I'm a mechanical engineer in apprenticeship and I'm generally informing myself of work in types of motorcycle mechanisms.
    I found an interesting crankshaft and piston rod design mere by the way and I wanted to ask you if it would be worth a video:
    Single crankshaft/single rod engines vs. Double crankshafts/ double piston rods engines
    (Neander Motors system)

  • @chandrurathnaswamy1276
    @chandrurathnaswamy1276 2 года назад

    Wow, that's an amazing explanation. Thank you for the enlightenment.

  • @stevenshizzle
    @stevenshizzle Год назад

    I love your videos dude. You do a good job of breaking it down. I couldn't follow the 5 cylinder magical engine stuff, but that's beyond a lot of us I think lol. Thanks!

  • @L-Noble.YT_Hi.Res-Soundminds
    @L-Noble.YT_Hi.Res-Soundminds 3 года назад +5

    I'm gonna become a pro watching this gearhead channel.

  • @Janni069
    @Janni069 3 года назад +4

    14:21 hahahah i swear this clip of Uzis "All My Chains" music vid was so unexpected and gave me a good laugh. Its without joking my all time fav uzi song 👍🏼👍🏼

  • @gavinsmith9022
    @gavinsmith9022 Год назад

    Great video my friend, learnt some new stuff watching this video, even after 30yrs of messing with engine.

  • @Fosten12
    @Fosten12 Год назад +1

    I really enjoyed it and found it helpful and informative

  • @aaaabababa
    @aaaabababa 3 года назад +9

    3:24 "belts run Dry"
    Laughs in french

    • @DSLRwalker
      @DSLRwalker 3 года назад

      Let me guess... 1.2VTi/PureTech from PSA?

    • @aaaabababa
      @aaaabababa 3 года назад

      @@DSLRwalker yea, but the germans are starting to do it now as well

    • @DSLRwalker
      @DSLRwalker 3 года назад

      @@aaaabababa Oh, i thought it's only PSA's thing.

    • @aaaabababa
      @aaaabababa 3 года назад

      @@DSLRwalker looking into it a bit, i think vw started doing it quite a while before psa did it.

    • @DSLRwalker
      @DSLRwalker 3 года назад

      @@aaaabababa oh i see, thanks for the info!

  • @Wicc3R1
    @Wicc3R1 3 года назад +71

    You didn't mention timing gears at all??? Well i know they are more used in big engines like trucks and tractors etc...

    • @manitoublack
      @manitoublack 3 года назад +10

      and real race engines (all F1 engines use timing gears)

    • @yesnomaybe3372
      @yesnomaybe3372 3 года назад +2

      @@manitoublack my old honda cbr250rr used gears. Makes a sweet whizzing when revved

    • @viperstrike3827
      @viperstrike3827 3 года назад +7

      ford 300 inline 6

    • @noahjohnston2577
      @noahjohnston2577 3 года назад +1

      They are also used in a very small engine being the one in the early cbr250s

    • @jaredmayer3960
      @jaredmayer3960 3 года назад +3

      Toyota in-line 4 and 6 from the 60's, 70's and 80's also had gears. Original old school gear drives needed a reverse grind cam because there were no idlers...iskendarian...awesome

  • @ph0ib0s1
    @ph0ib0s1 3 года назад

    Excellent, very well researched and presented. Learned a lot, especially about the nature of chains.
    Riding a motorbike 30 years ago, the stretching was so bad, you had to readjust the rear wheel distance every 1000 km. With the modern chains, you ride 8000 km and there is little or no stretching noticeable. Without lubrication, 30 years ago your chain started to rust and failed within weeks. Modern chains (O-ring) take a lot of abuse and work well for months without external lubrication at all.

  • @dennispierson5607
    @dennispierson5607 3 года назад +1

    You are an entertaining speaker. You put expression into your voice, face, and hands. I enjoyed your presentation.

  • @ToyotaLEngine
    @ToyotaLEngine 3 года назад +5

    I think both are reliable since the companies continue to produce them. Maybe I prefer the timing belt since it is easier to replace than the timing chains that are inside. I hope I'm right.

  • @onamission1848
    @onamission1848 2 года назад +3

    I wish you would have talked about the rope. I know it came in on 3rd but I still would like to try it in my car.

    • @boomboombaby9140
      @boomboombaby9140 2 года назад

      The rope is used to pull a vehicle using another vehicle if you don’t have a tow truck if your belt snap or your chain skips lol

  • @howebrad4601
    @howebrad4601 Год назад

    your videos are very informative and very well done

  • @regisphilmn
    @regisphilmn 3 года назад

    Subbed and dubbed the bell. You are seriously funny, intelligent and interesting. Like the videos!!!! Keep up the great work, love the content done here!!!!

  • @ShiroSama1
    @ShiroSama1 3 года назад +5

    The moment I seen the L24 and Z you got a like and subscriber :D

  • @brianb-p6586
    @brianb-p6586 Год назад +4

    It might have been worth mentioning that long chains and long belts both need tensioners, and to describe how they use different types of tensioners.

  • @chrisreynolds3204
    @chrisreynolds3204 2 года назад

    Very informative and great presentation of material.

  • @DaleC5195
    @DaleC5195 Год назад

    Love your videos!! I'd be interested to see one like this on throttle/throttle bodies (like the evolution of mechanical to modern day electronic ones)