Timing belt basics- belt seems too small

[Walker944]

Ok, I'm changing the timing belt and balance shaft belt on my '91 944 S2. I've had the car about a year and doing this for the first time. I've changed the belts on my early '85 and 86 951, but haven't yet had the pleasure of working with the mechanical tensioner.

After a great deal of aggrevation, I've removed both belts. I had to remove the tensioner, which some procedures said wasn't necessary, but there is no damn way the old timing belt could have been removed, without first removing the tensioner. After a significant fight, the tensioner is back on. Ok...that being done, I am in the process of putting on the new timing belt, but it seems like it is about 1/4" too small. I'm attempting to install with the tensioner retracted and locked down, so that there is no tension. There is no way the belt is going to go on. I checked the part number...it is correct.

It's got to be something I'm overlooking.

Also, the procedures I'm using state that the tensioner assembly can be removed by removing three bolts that are behind the assembly. This doesn't make any sense to me. I don't see anything that looks like what this is referring to. Is there a way to remove the tensioner without having to deal with recompressing the spring to get it reassembled. That's a real pain.

If anyone has gone through this process I'd appreciate hearing from them. And actually, I think the best way would be to have a conversation.

Any help would be appreciated. Thanks. Mike

Has anyone run into a problem installing the timing belt on the >'87 944 in which the belt seems to be too small?

[Lawrence Coppari]

Physically compare the two belts out of the car. If they are same size, then it is a precedure problem. Place one on top of the other on a flat surface - so they have same axis - and compare.

[ChrisBennet]

I must have a had a fit problem on my '89 S2 because I remember comparing them. What I think is important is that they have the same number of teeth. To compare them I:
-Turned them inside out so the teeth pointed out
-Held the belt up to each other so the teeth "meshed" like gears
-Made chalk mark across the edge of both belts
-Used my fingers to hold the belts together while I pulled the belts through my fingers until I got back to my chalk mark.
-If the marks line up, the belts have the same number of teeth.

The first time I did the belts (3-4 years ago) I removed the tensioner like you did (disassembled it). The whole tensioner will come off as an assembly, you don't need to disassemble it.
-Chris

[Scott R]

Yes the bolts are not visiable due to the design. But they are there. Remove it, route the belt then reinstall the tensioner.

[Walker944]

Thanks guys! What a pain, but the job is done and the car actually started and runs great!!! I found the three hidden bolts and removed the tensioner. However, getting the belt on was still a major arm wrestling match. Muscle won out over machanics in the end. I don't think I've seen a correctly written procedure for doing this job. Several of the documents I read said the power steering belt pulley does not need to be removed... I hardly think that is correct. Wasted a lot of time trying to not have to take off the pulley. In the end, though, all worked out, this time. Thanks to the comments from the above board members.

Mike