How to check timing belt alignment?

Technical and Repair Discussions

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PostPosted: Thu Sep 03, 2015 7:47 am
Spun Sunday and did not get clutch in soon enough to prevent a stall. My car timing cover has the 5/8 inspection hole at top. But don't know what I am looking for to confirm timing belt didn't skip a tooth. See what appears to be a pulley with a 1/2 inch hole through it and behind that a single dimple appears when the hole is at 12:00. What is supposed to line up with what?

Engine starts fine and seems to run ok but we were in rain so couldn't tell if it is pulling at full power.
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PostPosted: Thu Sep 03, 2015 10:25 am
There is a little pointer on the cam pulley. It should line up with the dimple when the crank pulley is at TDC. I think in the manual they say to take the crank pulley off to see the reference marks...
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PostPosted: Thu Sep 03, 2015 2:24 pm
After taking the crank pulley off you can mark it with a paint stick on an exterior portion of the pulley and plastic cover so you can skip this step in the future.
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PostPosted: Thu Sep 03, 2015 5:42 pm
Dog Licked Racing wrote:After taking the crank pulley off you can mark it with a paint stick on an exterior portion of the pulley and plastic cover so you can skip this step in the future.

It can also help to put dots on the cam marks, then you can use a timing light to check - I will risk displaying my ignorance by saying the light needs to be advanced 27 degrees...
Dave Harriman
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PostPosted: Fri Sep 04, 2015 7:50 am
When the timing belt on these engines (gen2) skips a tooth, is it really obvious from the way they run?
Scott Ross
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PostPosted: Fri Sep 04, 2015 9:00 am
I can manifest itself, if retarded, by "lying down" (running out of revs) on straights. If advanced, you'll see it rev up faster to redline. That's what happened to my GEN2 at The Glen Major last year. Ran great! Until it whacked an exhaust valve on trailing throttle entering the Heel of the Boot. The second I picked up the throttle I knew it was GEN3 time. Blammo! What lovely, symmetrical hole it made in the number one piston...
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PostPosted: Fri Sep 04, 2015 10:30 am
Yep, I thought this was a Bigfoot type scenario as I had heard of it many times but had never seen it in the wild myself... that is until Gateway a couple of years ago when Tim Blakeley was 8-10 MPH down going into T1 and no one could figure out why. We floated the idea as a last gasp measure, Dalrymple checked and sure enough... next session Tim was back in the hunt.
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PostPosted: Tue Sep 08, 2015 3:22 pm
I've experienced the belt jumping forward two teeth, and backward two teeth.

If your timing does check out okay, the next thing I'd suggest is to clean the MAF sensor with the CRC spray product for that purpose. I've had a dirty MAF be the culprit when my 1.9 engine was running flat about seven years ago.

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