How Come Timing Marks Don't Always Line Up Perfect?
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- Опубликовано: 1 окт 2024
- Ever do a timing belt or chain and you go to line up the timing marks and find that they’re just a little bit off? This video has the answer to that question.
Also, if you ever wondered how many camshaft rotations it takes for the same tooth on a belt to come into contact with the same cam gear on a Honda D series engine, this is your video.
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Stay Dirty
ETCG1
I timed my car 4 times with all the marks lined up, once i rotated the engine back it never lined back up, i was going insane. Thank you so much for this video. I can breathe a sigh of relief now. My family left me alone in the garage because i was yelling so loud to myself😂😂😂😂
This was me rite now until i seen this lol
It’s happening to me now 😂😂😂😂
Same.. LMFAO
I did the same removed belt 7 times so far 🤬🤬🤬
Hahaaa thats why i come here.
Eric!!! Where was Count Dracula??? One rotation...Ha, Ha, Ha, Ha.....Be Safe Stay Dirty
I just did a timing belt on a 3.0 accord, I noticed they didn't line up perfectly. I was hoping it was normal.
I thought about that for a couple of minutes the first time I noticed, then I slapped my forehead for not understanding right away. Of course there is no specific limit of the belt length, it is as long as it needs to be to get around all the pulleys. The key to timing is that there are twice as many teeth on any camshaft pulley as on the crank pulley. The belt itself is only a passive participant, much like the road in a Nascar race. Even a small uniform stretch will affect the cam and crank pulleys equally, and timing stays in line! Manufacturers like to choose common lengths just so their parts dept can supply the same part to many engines. The mark will move around the perimeter of the belt path by exactly twice the number of crankshaft teeth every cycle, so the mark on the belt naturally creeps even without somebody planning it out. They aren't confined by the notion of keeping the belt length to pulley length to a specific ratio. The mark doesn't even have to return to home after a specific limit, though with the carefully designed notch spacing it will seem to do that because the length needs to be an exact multiple of one notch length (so that there are no gaps where the belt is joined end to end in the factory). As long as the pulley timing marks are aligned properly, the universe is in sync.
I've read a lot of fun comments about this video. This is fun too, but it's also the best explanation I've seen. Great comment. Good to see you Spelunkered.
it would be one very odd "short engine" to make it line up on the cam every other rotation even (belt would be exactly 2x diameter of the cam, lol)
the longer the belt, the more rotations it takes to line back up at the cam and 2x that at the crank since cam runs half the rotational speed. rocket surgery =p
271 rotations to get the marks to line up again on a Subaru EJ25 (2.5L motor used in WRX/Sti and other Subaru models)! Eric should consider himself lucky that he didn't try this experiment on that motor!
P.s. thanks for the explanation!
yeap, exactly. when we make some custom engines, theres actually a few different belts that will work on something like...
lets say, a RB25/30 (rb30 SOHC block, with a RB25 DOHC head on it) , depending on where the new tensioner and idler pulley locations are,
anything from a 250 to 255 tooth belt, usually we'll use a 253 tooth belt,
just to have an easier time installing the belt, without too much slack
Your comment fully explained it best! Thanks! 😁👍
How many licks to get to the center? Has now been answered!!!!!
BS! The "hunting" of the belt is a function of the ratio of teeth on the belt to teeth on the sprockets. This has NOTHING to do with the alignment of the timing marks on the sprockets and block/head. Which depends on the ratio of teeth between the crank and the cam sprockets (1 to 2 for 4-stroke engines), belt tension/stretch/wear, the precision of the belt manufacturing, AND the actual distance between the block and head. How many times has the head been surfaced? Is the head gasket thinner or thicker than stock?
I was going to say the same thing, albeit a little nicer.
I got this information from an engineer. It's done to minimize wear on the system according to what he told me.
@@ETCG1 I think there might be confusion on what you mean when you say "timing marks". The timing marks on the crank pulley and cam pulley (if it's got marks) should line up within a fraction of a tooth with every rotation, while any pre-printed mark on the belt itself (or one you make) absolutely should shift as the crank is repeatedly rotated to minimize wear on the belt.
@@petermescher332 exactly. The belt processes around by some number of teeth per rotation, while the pulleys stay in sync.
Say the crank pulley has 30 teeth (the cams have 60), if the belt has 301, every 10 crank rotations a mark on the belt would move back by 10 teeth behind the timing marks on the pulley and block/head...and every 300 crank rotations the belt mark would be back aligned? But none of this has anything to do with the timing marks on the crank and cam being off by some fraction of a tooth.
@@ETCG1 no matter the position, the belt length and pulleys stay the same. Yes the belt position on the pulleys drift by tooth but the actual true crank/Cam alignment stays true. This has no impact to the true position of cam timing. When installing a new belt with the marks in place, any variation under a single tooth can be attributed to variation in machining or tension. Often the marks will align more true after rotation and slack is redistribute. Often in high performance applications we use a degree wheel and degree the cam to account for such variances as they can accumulate into multiple degrees when head gasket sizes and machining variances are taken into account.
Wow... very interesting, never heard about "hunting" before. Never told us that in tech school. Learn so much from Eric, thanks 🙏
I believe final drives are usually the same, and for the same reason. it spreads out any unevenness in wear - rather like rotating your tyres. :-)
@@aussiebloke609.
@@aussiebloke609 ....
@@aussiebloke609 mc..... El problema. M. ...mc
Thanks Eric. I’m doing the belt now and was not sure why the marks weren’t lining up after rotating the crankshaft. You answered the issue perfectly.
You bring up a good point, Eric. I remember doing the timing job on a 2001 Camry V6, and customer had bought the timing belt kit himself. I recommended buying the Dayco or Gates timing kit, but he went with the dirt-cheapest option he could find (which always surprised me when he did that, because he was certainly well-off, but never understood the value of buying quality parts). Anyway, the marks on the timing belt would not line up with the cams and crank marks no matter what orientation I tried; so, frustrated and concerned, I had him go buy another new timing belt because I wasn't comfortable not knowing if the belt was spaced properly between the pulleys. Sure enough, with a Gates timing belt, it lined up perfectly. It could very well have been fine, as evidenced by your video, and knowing that now, I could have probably gotten away with it, but since I had never done one of those engines before, I wasn't going to take any chances and have to do it all over again!
sometimes those people are well off BECAUSE they are miserly. If you are always spending extra on everything, you tend to have a lot less overall especially if you are making modest income; but if that same person penny pinches everywhere, it can have a huge effect on savings and therefore you appear more well off (ofc your guy could be a millionaire, but to some extent it still applies ... but you did say a 01 camry, so probably not 'rich').
And to be clear, sometimes those cheap things ARE the same. Go to Wal-Mart. Look at Melitta coffee filters and then Great Value coffee filters. The only literal difference is the bag they are in and how much melitta cares about how centered that stack of filters are in the bag (they care very much, and the display cases, they need to be lined up straight too). I worked for a company that made them, the difference between runs was a bag switch and if the machine was slightly off, how finicky you had to be straightening them in the bag and keeping up with the machines. This company also made wet wipes, Clorox had their own line and product (they owned it) but the other lines for store and other brands were pretty much the same outside changes for 'natural' or brand specific scents (rare); and the hospital only line.
The quality was all good, the company wasn't bad; just know that many products are a label or sometimes a container change, but can be the exact same product inside. If you ever wondered why something looked very similar or smelled pretty much the same, that is why. The products are basically contracted through other companies that focus on that industry.
I worked for dayco at one point, they shipped hoses to a lot of places including actual manufacturers, not just your local parts store. If someone has that knowledge, they may just buy the cheap generic thing because they truly do believe it to be the same; and I guess he trusted your judgement and realized they could be different as well. That would be my attitude towards it except I usually do tons of research first, and hopefully if I found a mechanic that respected my efforts and willing to have a short conversation about the parts I want to get to put on the car, we wouldn't have one of Eric's other video's problems, the customer that buy bad/wrong parts and makes their life harder; that would never be my point, I just want to know what I put on and would like to purchase it. Like if I wanted Idemitsu oil in my car instead of generic 0w20 they get in bulk because it is proven to work in rotaries as it is what Mazda used at LeMans and in their race series to this day, it was developed specifically for the rotary and its use in being used in the combustion chamber to lubricate the seals and burn cleanly. (that is the type of research and detail I consider respectful to a mechanic that respects me, but what the hell do I know, I'm just passionate about the cars I own and want as much involvement as I can get, but I'm clumsy when I work on cars and usually hurt myself and sometimes the car, so I try not to do major stuff any longer so I don't break something (car or self!)).
@@kuromurasaki5273 You scratched the surface with this mindset, having capital allows you to be opportunistic with your investing. But this is a situation where you have to calculate if the upfront cost savings offsets the amount of time until the next belt change and the increased odds of the belt snapping and seizing up the engine. I would argue with the risk to reward ratio of purchasing a compentnet as important as a timing belt, you're much better off spending 100 dollars more to leave you that cushion for what if it does snap and costs you 4-5k towards an engine swap.
Eric, I think you're a bit confused on why the belt or chain hunts. The sprockets teeth are not offset, they are symmetrical. Having them asymmetrical would be diffcult to time and correctly align and require a keyed belt or chain and cause problems especially Piston to valve or valve to valve contact on interference engines.
The belt or chain itself will always hunt because the difference in sprocket sizes and number of teeth on belt or chain. *large cam sprockets, small crank sprocket*
The difference in these sizes make it appear the belt or chain has shifted or is hunting but not really, it's due to turn ratios in cam to crank, I beleive it's 1 complete revolution of crank for every quarter turn of the cam on the 4 bangers. The belt in your case took 52 revolutions of the cam due to the number of teeth on the belt, if that is a d16 engine, it will use 104 tooth timing belt (go find the old belt and count, I bet I'm right), divide that by 2 and you get 52. That's how many times that belt has to go around the cam before it lines up again. Even though every 4 revolutions of the crank makes one complete revolution of the cam itself.
The TDC marks on cam and crank will always line up when cylinder 1 is TDC, always! That's why shop manuals tell you to rotate engine several times by hand and verify the forged alignment marks and ensure that nothing odd is happening with the tensioners or slack guides causing it to go out of time.
Which is why it's recommended to bring the engine to TDC before you do a belt or chain replacement.
Absolutely correct. I would add that the reason timing Mark's dont always line up is due to a combination of initial manufacturing tolerance, cylinder head gasket compression (which affects the distance between pulleys, cylinder head re surfacing (which reduces the distance between pulleys and belt stretch. Additionally there is a measurable change in distance between pulleys when tbe engine is hot. Thermal expansion is a notable effect.
Holy crap Eric, bet that was a workout...
Heck yeah! He should show off his guns afterwards. Kidding. Lol
he had the plugs out i think
@@360fanboy360 smarter not harder, right? Lol
This really threw me for a loop the first time I changed a OHC chain. I rotated the crank a couple of times to verify alignment, only to find the links WAY off. But the TDC marks showed that the crank and cams were still in sync, and that's all that matters.
This is the biggest load of crap I've ever heard. There is no design in having different teeth hitting different slots on the belt/chain. It just happens because of the different ratios between the 2 sprockets and the ratio of teeth and slots on the belt/chain. You would have to specially design a motor to get the teeth and slots to match up every time not the other way around. Which brings me to another point, say no to crack!
Thanks dude, you've been here for me for the last 5 years. Learning how to fix my cars and helping troubleshoot problems. I couldn't have done most of the work without you and this channel. Thank you Eric.
Glad I could help. Thanks for the comment.
OUTSTANDING video, Eric! You are the only guy on YT who has addressed this issue, as far as I know!
It explains my OCD worries and still having an engine that beat ass after a head gasket, water pump, and radiator; at different times in one month, and still breathing like a beast. It made me sketchy, about the work I had done, but after lifting the cylinder head, slapping it down twice, and revving harder than when I bought the car, I felt satisfied enough. All my worries on my first timing/head gasket job, over less than a tooth. Of course they won't say that in manuals, or most people online, liability reasons. Though, all the mechanics around me always told me not to sweat the small things like that here, it's nice hearing the logic behind it. Thanks again Eric! I would rather have a teacher like you than most others any day, keep at your approach and realism, I believe there are many that appreciate it.
Okay, what is going on here is there are three different marked items that need to eventually come back into sync. It's not just the crank pulley and the cam pulley correlation, better described more like a crank and cam pulley correlation to specific timing belt tooth. It just so happened to take 52 revolutions to get the mark that he made on the belt to line back up on that same cam sprocket tooth and land on both sprocket timing marks. Though it never went out of correlation / time. One last way to think of it is for example 60 teeth on cam pulley 30 teeth on crank pulley is a 2:1 ratio. But let's say the belt has 300 teeth.. the belt would throw in an additional ratio in the equation. I hope that makes sense, cuz I got no time for math. 👏👍😀
Excellent video Eric, I don't think I've seen any auto repair channel even discuss this topic. Thumbs up!
Reason number 14,973 why I love the internet.
I'm putting a new timing chain on a 3.7 L Ford duratec, I couldn't figure out why the timing marks would point in the right direction every 4 Revolutions of the crank, but the timing marks on the Chain we're always way out of whack. I suspected it was something similar to hunting but now you have confirmed it. And you just saved me 5 hours of misery. I owe you a beer. Thank you!
It's always great to know when my work helps people. Thanks for the comment.
Cool topic! Ah Honda, anti-clockwise rotation..
My thoughts too .i never rotate my engs in the opposite direction from normal rotation .not sure if it matters just something i dont do
Yep. Can't use the time-tested starter trick to break that crank bolt loose. Honda should have made them left-hand thread.
@@derekholdt747 question. Is a normal bolt, left or right hand threaded?
Only older honda rotate this side
@DE Nichols // Standard conventional threads are right-handed
The perfectionist in me doesn't like it, but, it makes sense. Thanks, Eric!
Thank you! I never usually mark the belt, just line up marks at TDC. On this 1.8t i did both and after rotating marks were off and I could not understand why. You have reasurred me!
Want to hear the most annoying sound in the world?? haha. This information is great, thanks Eric!
Years ago, my shop "mentor" explained this to me, but I had neither the apptitude nor capacity to understand. 22 years later, Eric explains it, and it's like: oh yeah, duh. That makes sense.
Lol i did this once too for absolutely no reason. Can't remember it being that many revolutions though 😮 but pretty cool that you actually filmed it 😆 thanks Eric
Yeah I remember way back when when I first did my Xterra 3.3 L timing belt same thing happened with me I couldn't figure out why the marks would not lined back up again turns out of course they are install marks only so the little white pen marks would never line backup but of course everything else did so little dimples drives you crazy sometimes thanks Eric
The biggest reason that throws marks off is when the head or block deck has been shaved. and i can tell you that isn't fun!!! Also I ecounterd once that the factory service manual was wrong... That was a long day...
I had to throw out the manual once on a Toyota Camry. Mid 2000's. What sucks, I managed to add a little thoughtfulness of my own and got it perfectly timed only to realize I had assembled something else imperfectly. I'd rather be lucky than good.
1st time go became several hours trying to recreate that magic moment. A few mm that Eric taught about can't be an inch. It would move out of time by nearly an inch! The way I put the belt down from cam to crank had to be few more, no a few less teeth many times over until I landed at the magic middle.
Prior to this engine, I was a first time go as they say on every engine I had timed. Usually laying down the belt impossibly tight is the solution then tighten the tensioner, but not on this engine!
There's a Kia that can cut your fingers off when it jumps. Why would they chose timing Mark's where the engine is so likely to leap violently? There had to be a way to make Mark's in a more intelligent engine position.
I learned in the comments that I should make my own Mark's at a natural engine position and then you can confirm it with traditional marks.
Kia literally put into the manual that the engine likes to jump from the Mark's. I felt like they were going to say next that they weren't liable for all the injuries they've caused.
Thankfully, I stayed safe.
Dutch, I can see how if you were used to timing an engine and then you did a shaved one that the rules will have changed a bit. Sounds like a pain in the ÷_
Especially if you don't know that it has had work done in the past.
That's also my lesson that I learned: ALWAYS MARK YOUR PULLYS. But I'm glad that I am not the only one that has this issue :-)
I have a 2000 Honda Civic LX I want to change out the belts, but what you said about the resurfacing of the cylinder head and block itself, how do know what size, type belt to get?? Will this glitch burn more gas just to keep ratios for a good running engine??
In theory, since the crank has exactly 1/2 the teeth as the cam, you should be able to line everything up with your painted timing marks 12 o'clock on the cam and 6 o'clock on the crank, spin the crank around 2 times your crank mark should be lined up with the cam mark? Ive found that sometimes you have to literally put the belt on one tooth off to take up slack or whatnot and when you spin it around like you did here all is kosher.
I once had to remove the Bosch fuel pump on a Jungheinrich forklift with a Perkins diesel engine,took me about 35min to align all 5 marks on the gears(no belt,no chain,5 sprockets)
The easiest way to change a timing belt is to mark the upper and lower sprockets, and put corresponding marks on the block or head. If you're rebuilding the engine then that's a different story. But if its just a belt replacement you just need those sprockets in the same place when putting the new belt on.
TargaWheels it does work but it’s not always the simplest or best way. Sometimes a valve spring will be under tension and when you take the belt off, the cam shaft will spin round a bit. Then you end up trying to put the belt with one hand while holding the camshaft in position with a spanner. Then you’re left wondering if a valve hit the piston crown and got damaged until you start the engine. The other issue is that if your old belt had a bit of stretch, you’re putting the new belt back on the wrong position which could be a tooth out. Sure, it’ll run but it’s not good practice. The best way is just to use the timing marks or better still, locking tools if you have them. If not, some engines can be locked with bolts in strategic places.
On my car there are colored markings on the head and block and sight holes on the pulleys that you line up with those markings.
Just sharing what I've been doing. Honda/Acura, Toyota, I've done it this way without a hitch. If it does move slightly I'll rotate it back when putting the belt on. After I set the tensioner I go back around and make sure all my marks line up.
Barry McNicholl Yes.! you nailed it,I I used camshaft locking tools on my GM 3.6 and I feel so mucho confident that I did right after every 2 turns the timing marks on camshafts are aligned with locking tools,those $18 that I pay for them makes me sleep well 🙋🏻♂️
@@TargaWheels what if I rotated the crank after I put the belt on, and when I looked after rotating a few the marks on the belt did not line up...
Thank you for making this video. I just about had a heart attack when I did my timing. I did the exact same thing other people did. I aligned everything spun the crank around numerous times to make sure that the belt marks came back around. I literally thought that I had bent all of my valves, lol. No more paying attention to the belt marks for me.
I'm happy to help. Thanks for the comment.
I changed the vvt sprocket on my Camry a month ago and The marking on the chain n the exhaust gear were off by a tooth or 2 , I was just driving myself crazy thinking about it and wanted to wake up early tomorrow and adjust it , even though the car works perfectly fine I guess I’m just a perfectionist. So I guessing this is normal and me trying to “adjust” it is foolish if the car runs great
That makes sense though because what’s the chances of the chain and gear or belt will always lining up perfectly , I guess as long as the marks are somewhere in the realm of where there supposed to be its fine
OMG I've gone through the timing on this Nissan Sentra 5 x now trying to get it to line back up, bout to lose it. Thank you so much for this
Americans are so funny: instead of doing some math on how much will it be if we add two apples to three apples in their heads - or with a pen and a piece of paper at least - they always shoot a video where they manually add three new apples to two ones and count them. Sometimes they explode an apple or two... to make it more american.
1) Timing belt 14400-P2F-A01 has 104 teeth.
2) Honda D-engine camshaft pulley has 38 teeth.
3) LCM (the least common multiple) for 104 and 38 is: 52x2 || 19x2 =52x19x2 = 988x2 = 1976
4) If you are rotating the camshaft pulley (38 teeth) then it will take you 1976/38=52 of camshaft rotations to re-phase (i.e. for your marks on the pulley and on the belt to come together again) - if you were rotating the belt then it would take you 1976/104=19 rotations.
You can count the number of teeth on the crankshaft pulley (actually, you don't have to unless you're an American: in a 4T-engine crankshaft pulley has 1/2 of camshaft pulley number of teeth, i.e. 38/2=17 for Honda D) and start from #2 to calculate how many rotations of the crankshaft one will need to re-phase the belt and crankshaft pulley teeth.
Bottom line which Eric didn't make clear: Honda D-engine camshaft is jumping 1/52 of tooth off the timing mark (if observed from outside of the rotation system) per every camshaft revolution; crankshaft timing mark is jumping off at 1/104 of tooth per a crank revolution. Think of it as of sorta vernier caliper thing.
And for those, who still can't make it: this has nothing to do with the phase between the crankshaft and the camshaft. It is only about marks on rotating pulleys and marks on stationary engine parts. After two crankshaft revs (or a single camshaft rev) your crank- and camshafts will always be in the same phase unless the timing belt/chain has been stretched.
Well put, but keep in mind that counting teeth on sprockets and doing math on a piece of paper doesn't make for compelling video. ;)
Eric, the most compelling video would be if there exploded two black chops in the background while you were rotating the things and counting teeth.
@@TheZzziggy I like it. You're hired.
Eric, hats off to you for having the time to do this workout. Over 50 times? I would give up after 5 times. I was so pissed off when I changed my first timing belt in one of my civics. I marked the old timing belt, moved the marks to the new belt to make sure everything was done correctly, and after rotating the engine, I never managed to get the marks aligned again. Guess what, I tool everything off, did it again, and the same thing happened. I just thought, possibly this is the way it is, god knows. Next day, me and my mate did it all over again, yes, 3 times in total, I just wanted to make sure I wasn't doing anything wrong before starting the engine for the first time after changing the timing belt. After the third time I just thought, screw it, I will start it, and it was ok. Now, before I attempted to change this timing belt, I watched some videos and so on, and I never came across about this so called " Chain or timing belt hunting" just after one year or so I came across another of your videos when you mentioned chain hunting, and I thought, bloody hell, this information is a bit late for me. It would avoid some phenomenal bad language used on the precess of changing this timing belt.
I feel your pain...took it 4 times on my panda
@@giogio4833 join the club 😀
Interesting it and I can't believe I guessed 52.😂
That's what I've been telling people all the time, when it comes to setting the timing on Honda engines. Just as long as the crank pulley is set to TDC, make the cam gear at closest as possible to factory specs. It will start every time. People have a tendency of setting the cam gear first and then the crank pulley, which leads to jumping a tooth or two and not starting.
Ive always wondered about this. I always thought it was a quality assurance issue. Now I know. Always best to hear it from Eric lol
Btw, my profile picture are a set of k20a3 cam shafts and gears lol
Thanks, I did not know about that. I wanted to check my timing belt on my Mitsubishi Lancer but i was so unsure about getting the timing correct that i took it to a mechanic shop to have it checked. Turns out it would have cost a lot less if i just did it myself. Thanks for making the video. If you can can you make a video on the timing belt replacement on a double cam engine japan made vehicle.?
Wow, All these years ,Never new. Thanks!
Awesome information Eric! I just timed my F-150 and was crapping my pants when i saw that the marks weren’t lining up!! Whew!
So it's the solution of (n*x) mod b = 0 where n is the number of teeth on the cog and b is the number of teeth on the belt and x is the number of rotations. And that proves that the honda engine is actually a hand cranked calculator in disguise
ONE DAY after my timing belt change on my 92 Acura integra GS! I was wondering the same thing 😁
Wow, doing dodge/chrysler 2.7 lined it up perfectly, rotated to watch them realign any one that's done anything with timing knows the feeling that over took me instantly when it never did line back up but I only rotated it 20 times maybe.
I work flat rate World as you know how that goes, never really noticed but I don’t mark new belt. When checking I’m more concerned that cams are lined up with crank before putting back together.
Now that just locked my brain up, for a belt to move place i would expect the drive to have more or less 1 tooth different, but surely that would make the timing drift off.
No that's wrong, so..
A belt with an odd number of teeth?
Yea, it is confusing, but somehow it works.
The timing marks line up half the time. The belt is just wandering through. They do this on motorcycle chains by having odd number of teeth on the back sprocket versus the front.
Final drives usually have hunting gear sets as well. It spreads out any unevenness in wear - like rotating your tyres. I think they do it by making sure the number of chain links or belt teeth can't be easily divided by the number of sprocket teeth. :-)
Think of it as a "lowest common denominator" problem in math class. 😉
Exactly. And the higher that "lowest common denominator" is, the more the gearset hunts. :-)
I'm having this problem with my 2005 Pilot. My son's mechanic friend is going to come over and help me out. If he is OK with it, I'll make a video. I'm having two problems. First the rear/firewall cam want to slip toward the firewall when I put hand tension on the belt in the place where the hydraulic tensioner would be. I can compensate for that. Second, when I do get the marks lined up, release the tensioner and hand crank for 2 revolutions both the front and rear cams are off one tooth. I can't figure it out.
Hi there plz can you help me out I try test that website you said I will answer but is not work so I have now 2012 Ford Focus se I change
Head gasket my self but won’t star the car now and I forget to pot marks on the timing chain plz tell me how I’m going to do it how going to link up
I have an question for you, I set an timing belt and the mark for the 2 top dead centers keep hitting dead on but no matter what I do the crank saft mark keeps landing slightly left of zero tried resetting it 3 times. It's on the 1990 3vze Toyota engine?
This has nothing to do with timing marks lining up. This has to do with cog/gear tooth ratios. For example, if you have a cam cog and a crank cog with the same amount of teeth the marked lines will line up every time when the belt marks come around. Timing marks not exactly lining up when you put the belt on has to do with an old stretched belt or belt slack when you put on the new belt. I agree, if it's less a tooth out its within spec since you cant get any closer unless the new belt is wrong or not made right.
For this "hunting" to exist the belt would actually have to change position on the belt, this would cause a valve interference catastrophe.
So glad i came across this video. I was so scared I jumped a tooth or two.. Turned it a few times and couldnt get my marks to line up again and just gave up.. This gave me a bit of hope back.
No shiz, it's actually my 21st today 😂
As regards the camshaft position being locked how do you prepare a cylinder head for a machine shop? Why are camshafts locked to swap timing belts when they can simply be aligned to tdc + timing marks?
I assume that this may also be because you want the impulse from combustion events to hit all portions of the belt, such that certain spots take all that stress at once and wear out faster?
My Ford Courier 2.0 did this and I didn't know why, Now I do! I counted 53 turns to get it back to "installation links to dots" and strangely it had 106 links...double the rotations..? It was a 19/36 gear set.
Ive been watching you for years and just realized I hadnt subscribed to your channel...I remedied that problem today...sorry about that
it is a function of how many teeth are on each sprocket and the differences in size of each sprocket x the number of chain/belt teeth....
Who ever told you about hunting, must have been referring to the computer's ability to adjust timing and "hunt" to optimize idle based on timing and VE settings. This is not related to the precision of timing alignment marks. Timing marks for alignment purposes, are generally not super precise, but close enough where if you are off by a tooth, it's very obvious. It depends on the make. Miata 1.6 marks tend to be dead on when viewed straight, where as 1.8 marks are slightly off, but again, it's obvious when you are off by a tooth, because they are "way" off.
Hi Eric "l think" you just answered my dilemma but can u plz confirm.
2000 xterra timing belt replaced. All timing marks lined up adjusted belt tensioner pulley. Rotated main shaft multiple times not paying attention to how many..... tried rotating backwards to get back to tdc and marks in place. Not happening. Am l good?
Hey Eric, I just replaced my water pump on a 2007 accent. I thought I reinstalled the timing chain correctly but the engine ticked and stalled out. How should I go about retiming my engine? TIA
I have a 2005 mitsu eclipse 2.4 with the timing belt . Looks like the timing on the oil pump gear is off 1 tooth could that make the oil can light on an off on the dashboard ? It starts runs an idles fine . Except it did develop a knock an 1 set of rod bearings needs changing . Wonder if it being a tooth off could throw the oil light an cause the bearing to go bad or would the oil pump gone bad all together ??? Any help please 🥺 !!
This answered my question, what about those Honda odyssey V6 engine? Does both front camshaft marks have to line up perfectly to the marks on the timing marks? My rear camshaft was off a little bit but mine van is running fine after timing belt replacement job. Could it cause a p0420 code for a little off?
26 jan 2019 5:22 pm est:
i wonder whether timing-mark tell distributor(former name for engine-control-unit),about current piston-postiion
source:
'A crank sensor is an electronic device used in an internal combustion engine,
both petrol and diesel, to monitor the position or rotational speed of the crankshaft.
This information is used by engine management systems to control the fuel injection
or the ignition system timing and other engine parameters. Before electronic
crank sensors were available, the distributor would have to be manually
adjusted to a timing mark on petrol engines.' in en.wikipedia.org/wiki/Crankshaft_position_sensor from google(car engine piston sensor location)result 1
i wonder how old-car determine when is the time to make spark-plug make spark to push piston to rotate crankshaft
On my 72 2.0 My timing belt is on right I think " Compared it with my 73 - but my timing light shows it's off by like an inch on the 72, Car won't run if I put at 6 before TDC. Could the Distributor be why it's not lining up right with the light strobe. The 73 strobes the light spot on 6 before TDC
Thanks. As a weekend idiot I've done about a dozen timing belts on my cars and have always agonized over those marks not being precise.
I am trying to do the timing belt on our 2008 Audi A4. The trouble I have is that when I get the crank pulley mark and cam gear mark to pointing correctly, the crank won't stay and slowly moves CCW, resting an inch or so off the mark! I tried going past the mark a little, but the crank still rotates CCW to the same place off the mark. I had loosened the plugs to make it easier to rotate by hand. Tomorrow I will try tightening the plugs to see if it makes a difference. Any one know the reason why this is happening?
Why would anyone thumbs down this vid? EXCELLENT INFO!
if they are ever so slightly off, and I have dual cams, then when my exhaust cam in showing TDC but my intake cam is a hair behind in rotation. which TDC mark on which cam gear should i use as my TDC when adjusting my valves?
Wouww. Everybody just shows how to rotate the pulleys but you are explaining what we should expect and why we should not surprise if we cannot align at the first place. Now it makes sense. The question is when should we align the timing belt?)I mean I want to change only tensioner. I am planning to use old timing belt. Do I have to still align it?
What up with the weird sound effects & what are they? So what does this mean? That you have to turn the engine over 52 times (+ or -) to know if your timing mark(s) are properly aligned?
So I’m not going crazy I just did a timing job on a ford f150 lined the timing marks up pulled clip and rotated it like 3 times and not aligned in fact keeps moving away.
all good sprockets are uneven, to spread wear, it was bad practise to have two cogs that are a division of the other or they wear badly. in this case the belt is part of the system
Cool video.
If the belt was off one tooth, what would the motor sound like would there be a noticeable difference? I have a j35 that is giving me misfire check engine light when I know I lined up everything properly. Could it be one tooth off and still run good?
It's not that it is designed in at all. It's a simple factor of how belts and chains work. Unless you have two equal sized sprockets a chain or belt can never hit the same marks every rotation.
Here is a simple thought experiment to understand it. If you take two equal sized circles you could replace the belt/chain with a bar attached to each sprocket on a rotating pin (Think how all the drive wheels are coupled on a steam locomotive) and the circles could still spin around freely cause they are 1 to 1. However, if you take a big circle and a small circle and try to connect them with a bar in the same manner they will get jammed up because the ratio isn't 1 to 1. Since a belt and chain doesn't have to connect at a fixed point on both wheels it avoids this inherent problem that bar links had.
thanks man, this saved me some grey hair, I changed my belt on my Lexus and after the first rotation it didn't line up any more...now I know why!
Great video and information! Was going crazy trying to line the timing marks up only to repeat this over and over again.
Didn’t know that. Then I thought about and I figure probably 4 turns.... man I was way off. How interesting.
Because the size difference in sprockets. American education system really failed us lol
I have a 05 sonata 2.7 with dual over head cams, the front bank (closest to radiator)rotates and lands drirectly on the mark, however the other cam skips right over it, any suggestions?
adding. i turned in my clio 1,2 2002 for timingbelt and tensioner change, after that my car dont go as fast any more..... im useing km/hour so top sped on it before was 160 km/h and pritty fast to go there to. now it go to 150 km/h and it takes long time from 135 km /h can it be one tooth wrong they set it ?
super crazy it’s actually my birthday that felt personal thanks etcg1!!!
I have a 1975 ford ltd, the timing marks are way off, i had to set timing with a vacuum gauge. what would cause the timing marks to be more than 20 degrees off?
Designed to be hunting? What the hell does that mean. Ridiculous. Why not designed to be lined up. Which Is what they make it clear you must do. Why don't they mention that ridiculous claim of hunting. It's obvious you are either repeating that phrase without thinking cuz if you did think about it you would realize it makes no sense. " yes let's design all this so everything works in sync but if the sync is messed up in a tiny way cuz it's bound to as things stretch and or wear or shrink but to we will say that we designed it to be hunting so dumb people can think it means something even though it doesn't but it sounds like it does if you are dumb." Designed to be hunting? No no it isn't. It isn't designed to be off a bit and then hunt to be on but only hunt never find cuz if it found it it would then not have to do what it's designed to do and that's Hunt. Ugh
The gears don't hunt anything. To make a belt "hunt" you need a belt with prime number of tooths like in this Honda it's 51 tooths since it starts over at 52. The TDC marks on cam and crank do not hunt.
That shit is magic
You’re referring to the installation marks on the belt right? I’m doing a belt right now where I cannot for the life of me get all three marks lined up even though all gears are correctly timed. Compared installation marks to the old belt and they look perfect. Do the marks ha e anything to do with structural integrity of the belt or just as a guideline? Because I would’ve started this thing up hours ago if someone can tell me they’re not that important.
Not sure "hunting" is the correct nomenclature, but if the concept of ratios as it relates to timing components wasn't intuitive or obvious to you to begin with, you should have stayed in school past 6th grade, and probably should not be replacing engine timing components.
so so so. i removed the timing cover on my 2011 v6 stang bc im doing the timing chain. i found the camshaft phasers timing marks dont align with the timing chain marks. Alldata says to put piston 1 at tdc which i did and the picture they show, the right side cam phaser is slightly offset pointing to the right and the left phaser slightly offset pointing to the left. however when i have my engine at tdc for poston 1 and the timing marks from the timing chain, the phasers dont show as the picture from all data. my right phaser is slightly offset pointing to the right as shown on alldata. but my left side phaser is more straight up and down. i want to know is this is anything very bad before i remove it. idk if this will mess me up during installation.
They don't line up on motorcycles either, drove me Nuts......then I realized this has Got to be normal......ONLY if it's a few millimeters....it it's looking straight up Crooked-off.....then you might need to play with it, to see if it's Really off, or not.
Question Eric! My time belt broke a tooth and the belt is slipping, when I try to align it I can't. Is there a way to align the engine without the belt?
2012 honda pilot. Two timing marks line up but one is off buy four teeth can I turn the one crank back to the mark with the belt off
The Internet says it’s only supposed to go through 20 rotations to four .. so it probably jumped a lot of gears to get that bad. 😂
Question....What causes a car to jump out of timing?Had this happen to my 2005 Honda civic.
this saved my life just about to strip the motor down as I thought I had jumped the teeth , now makes sense why the mark on the chain disappeared but my sprockets remained in line
168 turns for Mini Cooper to line up colored links with factory marks as per manual and I have done it myself as well, lol.
Thanks you I was so close to pulling the belt off again. I noticed my crank and cam gears we're in the right spot but the belt was way off. Short story thank you
I guess if you video the timing light on it, it wouldn't show without a high shutter speed camera that you could slow the footage down a bit instead of spending all that time hand cranking speeding up footage instead. Thanks for going through the trouble anyway
i ave a problem with my d16 engine, it idles fine but when it reach like 1500 rpm it start to behave like it is missing until u pass 2000rpm, u can tell me wat could cause that
And if i mark the crank pulley gear alligned with the belt, i Imagine that they doesn't correspond at all. It's correct?