Question about Installing a Timing Belt...

[my3awds]

It has been brought to my attention that I may be running poorly because of a misaligned timing belt. So I wanted to redo it today. I checked the timing marks on the cam gears yesterday and the acutal marks on the gears 'seem' to line up when they come around. Also, the mark on the timing belt seems to match up with the timingbelt cover marks.

Here is my problem: I've rotated that thing probably 50 times and I haven't been able to get all of my marks to line up like they do when you first install the belt. I can't seem to get the cam marks to ever meet up with the belt marks, and the crank mark to match up with the belt mark all at the same time. Is this normal?

If it is my belt that is causing it to run poorly, I imagine that since I had the heads freshly rebuilt, the HLA's hadn't set proprly when I installed it, and now after running it, it's caused my timing to be off a tooth (maybe?). Anyone running without a timing belt cover? I know it's not recommended, but I'd like to run without one for a few days after I reinstall the belt just to see if it jumps.

Thanks~

[Legacy777]

It's fine......the belt marks don't need to line up with the gear marks.

All that is important is that the pulley & gear marks line up with their appropriate marks on the timing belt covers and oil pump housing.

[thehookeup]

once you line up everything, and set the belt, and then rotate it a couple of times. it will be off just slightly. it will never be exactly on. it can vary up to half a tooth width off from the marks.

But as long as all the marks on the belt line up with the marks on the gears. youll be fine

[entirelyturbo]

I have to disagree Josh.

When I do a timing belt, I make sure the marks on the belt line up with the marks on the gears, because those marks should line up perfectly. The marks probably won't line up exactly with the marks on the timing covers, but as long as the belt marks line up with the gear marks, you're golden. If they don't, then your timing is likely off.

Also remember to use the mark on the BACK of the crank gear, on the crank sensor tooth, NOT the one on the front. That mark, I believe, is to indicate BDC on #1, and has nothing to do with the timing belt.

[my3awds]

Ok thanks for the replies. Eventually though, shouldn't at least the cam gear marks and the crank gear mark go to their perspecitve timing mark at the same time, regardless if the belt marks match up? Because that hasn't happened either.

I'll take pictures of before and after the reinstall. Maybe some of you can help indicate if I was off by alot or not. Thanks again.

[sammydafish]

subyluvr2212, you're not reading the thread.... once the car is run the marks on the belt will not line up anymore. You've have to turn the engine over exactly the amount of times that there are teeth on the belt before the mark would line up again. Josh is right on with what he's saying.

When you're putting the belt on, yes, the marks (on the belt) need to line up with the marks on the gears. But the marks on the gears 'may not' line up perfictly with the marks on the cover. They should be within half a tooth though.

[entirelyturbo]

Okay, I see what you're saying. I stand corrected. Sorry Josh.

[Matt Monson]

If the belt was set up properly in the first place, what I am going to guess has happened is that the timing belt tensioner has failed and allowed the belt to skip a tooth or two. This isn't a big deal since this is a non-interference engine. A friend recently had the same problem on a v4 STi and his valves smacked the pistons on one cylinder...

[my3awds]

Id like to thank everyone who has helped me out because it indeed was 2 teeth off. And I answered my own question by diagnosing: The center crank gear is exactly 1/2 the diameter of the cam gears. So every 2 complete rotations for the crank gear, ALL the timing marks should line up. In other words, all the timing marks should line up when initially looking at the cam gears.

Threw everything back together, fired her up and she sounds sooooo lovely. Idles nicely, revs nicely, and sits very still I plan on replacing the o2 sensor and plugs tmw since I'm sure they are pitch black from running the car like ass for 3 days. But I am so happy right now. If I could buy everyone a pint here I would. You guys roxorz.

[Richard]

How can you tell that you might be off a tooth or two? Is there an engine code that could pop up? How would the engine run? I ask this because I did my water pump a couple months back and I wasn't 100% happy with how the belt looked. I'd say close to 95% happy, but still, something with the belt and the cams made me 5% unsure. Didn't look exactly 100% deadnuts, and being a persnickty second guessing bastard, I want to be 100% sure that everything's right on.

[my3awds]

If you bought a new belt, there should be marks on the belt that help indicate where the timing marks should go. When I put the timing gears to their mark, the mark on the crank pully was off 2 teeth btdc. The car ran very poorly, but would not give any codes. From my understanding some timing belt jobs will look slightly off on the cam side, but they should be pretty close. After I redid mine, they were spot on. Car runs well now.

[THAWA]

I have to disagree Josh.

When I do a timing belt, I make sure the marks on the belt line up with the marks on the gears, because those marks should line up perfectly. The marks probably won't line up exactly with the marks on the timing covers, but as long as the belt marks line up with the gear marks, you're golden. If they don't, then your timing is likely off.

Also remember to use the mark on the BACK of the crank gear, on the crank sensor tooth, NOT the one on the front. That mark, I believe, is to indicate BDC on #1, and has nothing to do with the timing belt.

Actually, with the way the belts are marked they dont always line up with the marks on the sprockets. They can be half a tooth off too. You just have to get everything close enough.

[sammydafish]

I have to disagree Josh.

When I do a timing belt, I make sure the marks on the belt line up with the marks on the gears, because those marks should line up perfectly. The marks probably won't line up exactly with the marks on the timing covers, but as long as the belt marks line up with the gear marks, you're golden. If they don't, then your timing is likely off.

Also remember to use the mark on the BACK of the crank gear, on the crank sensor tooth, NOT the one on the front. That mark, I believe, is to indicate BDC on #1, and has nothing to do with the timing belt.

Actually, with the way the belts are marked they dont always line up with the marks on the sprockets. They can be half a tooth off too. You just have to get everything close enough.

he's already been corected and admited his mistake...... read up a few posts