AJ AJ

Hi - so I've got my new water pump in and belts back on - It runs. I checked the belts and noticed that the new belt was in contact with the new water pump - it appears to be about 3mm too close to the engine. I checked the diagram and noticed that parts 22 and 31 were not there. They didn't come off the car I'm pretty sure. It looks like a washer and shims. That would push the tensioner out and hold the belt away from the engine?


The tensioner has no play where the washer and circlip go to hold it on the spindle. Has anyone got any ideas of what I've done wrong?


Many thanks.

Charlie

there are two types of bearing pins part 13 for the 968. The later cars had an improved design. I believe the in this part diagram this is the later part. Part 21 are o-rings and part 22 are shims. I assume the improved design was to make a better seal and keep grease in place. The best I remember the earlier pin did not use 2 o-rings.

The tensioner arm when placed on the bearing pin will have very little horizontal movement. It is a tight fit.

Charlie

Show a picture of the belt on the tensioner pulley.

AJ AJ

I'll pop into the garage and take a photo. The tensioner arm has no free play (well maybe 1/1000 if any - certainly not enough to take another shim. My car's a 92 - so probably without the O-rings. I'd read an forum post prior to the job where a guy couldn't remember which side the shim went on - so i'd only accounted for the one shim and I've not found another lying around. I'm wondering if the new water pump has a slightly thinker casting?

AJ AJ

It's quite hard to get in there with the camera. The belt is butted up against the flange at the rear. I can't feel any play in the pulley at all the brass bushing feels good and there was grease on it when I removed it.

Charlie

It looks as if the belt is riding too far back on the cam sprocket. water pump pulley and tensioner pulley. Do you have crank pulley on correctly????

AJ AJ

Is it possible to get it on wrong? I didn't remove the crank pulley, but did remove the alternator pulley and flange. - the only bit that I think would be possible to get wrong is the flange?

Charlie

I suppose you could put the crank pulley on with the flange the wrong way. If it is correct then I would think you have to have a water pump problem. The belt on my 968 runs where the brown marks are on your cam pulley. I just measured and my belt is around 1/16 of an inch from the front of the cam pulley. Yours appears to be much more, that is why I was quetioning the crank pulley.

Charlie

Can you get a pic of the crank pulley??? There has to be an explanation.

AJ AJ

I've had a good look at the crank pulley, but the belt is too close to the engine there too. There's nothing touching it to push it over, like a flange or similar. I've worked out a way to fix it, but it's not really legit and does not address the cause. If I put a 3 mm washer behind the spindle (part 13 above) it'll track the belt in the correct location. This does not address why it's moved over though. All I did was change the water pump. The uro pump that I put on appears to be 2-3mm thinker - but this would not change the track of the belt.

Charlie

If you removed the spindle (part 13) then be sure to use red loctite when installing. I would check and make sure you have the metal washer between the crank pulley and oil pump drive gear.

thomasmryan

the spacing looks a bit too much on your tensioner cog. here is a picture that kinda shows the clearance. you might ask someone for a measurement that has their covers off.

uro parts are famous for being less than stellar.

AJ AJ

The clearance between the roller and the tensioner body is 1.6mm - that would seem about right unfortunately - there's no play there either. I'm thinking that these rollers were all replaced by the previous but one owner - He had a lot of work done and all the rollers, belts, pump were all replaced.

I'll lock the flywheel when i get home and pop the crank pulleys off - I'm sure that the issue must be there - somehow.

thomasmryan

The flange on the crank and tensioner cog are what keep the belt aligned so if those check out, it might be a wandering pump. You might take the belt off and use a dial gauge on the water pump pulley to check for radial runout.