I decided to to get started on changing the timing belt tonight and I ran into a little problem. I lined up the tdc mark on the cam and made sure the mark for crank was set too. Removed the timing belt and tensioner. Then I tried to get the crank bolt out(impact gun) to get to the seal behind it and now I'm a little worried I might have crank position off. I think the crank moves 2 full turns for each rotation of the cam sprocket before the marks line up again, but i'm not 100% sure about this. How could I tell for sure that the crank is set right when I put the new belt on?

It looks like the No. 1 cylinders up each time I turn the crank a full turn to the mark. Is it possible its off 180 degrees from the cam when it's at the tdc mark?

Thanks for your help guys!!!! I really appreciate any advice. -Peter

 

Do not turn the crank with the timing belt off more than a few degrees. You will hit a open valve if you do and probably break it.

 

Wouldn't the valves be closed when the mark on the cam is aligned with the valve cover?

 

http://www.audiworld.com/tech/eng.html

 

Didn't you insert that plug into the crank to lock it before you went at the sprocket?

 

Here's what you do. First, make sure the CAM gear is a little off of TDC. Slowly bring the CRANK gear in line with the TDC mark. Then, bring the CAM gear back in line with the mark. Install your belt and slowly turn the CRANK gear by hand two full turns. You will feel resistance during the compression stroke. Stop and wait a couple seconds, then continue turning. If you still feel resistance, stop and double check everything. While the CAM shaft does turn twice as as often, I don't think the valves are ever open when the piston is TDC.

 

That plug is only for V6 engines

 

Well I got it all back together last night and she started right up. I was really getting worried that when I turned crank trying to get the bolt out I could have bent a valve. It couldn't have turned more then once(one full turn) and I think I turned it right back to the same spot it was in before since I marked a spot on the sprocket/block. I also counted the teeth on the belt between the mark I made and the one thats already on the upper cam sprocket to make sure it was the same as before with the old belt.

Anyway I went for a drive earlier and it seems fine. The coolant was at the lower level in the overflow tank so I filled that to the full mark. It was alot of work and I'm just glad it's over. I hope there isn't anything else for a while!!!!

Thanks for the replies.

 

ohh yea, and another thing. The belt was alot looser with the old style tensioner and I could almost slide it off the sprockets by hand!!!!

99.5 with 63,800miles

 

Nice job.

I just did my timing belt this weekend. Welcome to the club!

My tensioner had broken, i found out after taking it apart!

I had to find TDC using a compression reader, then lined up the top marks, then adjusted the crankshasft some because I think my belt jumped a tooth or two. On the dampner pulley that connects to the crankshaft, there is a mark that lines up with a mark on the lower timing belt cover. That is what I used to make sure the camshaft and crank were in the right positions.