Timing Belt Rubbing Rear Cover

[tooter884]

Prior to refurbing my '83 944, the timing belt was rubbing the rear cover in the area between the idler/roller and cam sprocket. The tensioners and idler/rollers were in very poor condition, and I assumed that replacing them would sove this problem. It did not. I have installed new tensioners and idler/rollers for both the timing belt and balance belt, installed new belts, and tensioned the belts with the Kriket tool. Unfortunately, the timing belt is still rubbing the rear cover. It is tracking flush with the rear edge of the cam sprocket, and toward the rear of my old-style water pump pulley. I'm sure the tensioner, idler/roller and crank pulley are installed correctly. The water pump has been working properly and the pulley appears to be OK, but perhaps a new updated water pump would solve the problem. Even though the timing belt is tracking toward the rear, does anyone know if the belt should clear a properly installed rear cover? Any ideas why the belt is tracking to the rear of the cam sprocket? What other gremlins should I be looking for? Could a too-tight belt cause this problem?

[SoCal Driver]

Tension pulleys have single flanges. The one for the timing belt should have it's flange on the engine side. The one for the balance belt should have it's flange away from the engine. There is also a flange on the main crank pulley. I need to go to the garage and check it's orientation.

[SoCal Driver]

The flange on the crank pulley is toward the front. The tension pulley is what sets the tracking for the timing belt around the crank and to the cam pulley. If the flange is toward the engine check that the stud is not pulling out of the block.

[Hank3G]

This is a hellaold thread, but it comes up first in Google searches for this problem. I have .02 to add to it because I had the same problem. Whoever designed the covers should be taken out back and put out of his misery.
There is not a fail safe way to secure the upper right part of the back cover. So, how if its rubbing there and all pullys are installed correctly and you still have chafeage do you fix it? I found the secret is in the air hose that comes from the cleaner to the back of that cover section.

Loosen the hose clamp holding the hose to the air cleaner, dont fully remove it. (not the intake hose, the one that runs to the belt covers.)

Twist it toward the rear of the car while looking at the other end where it is clamped into the rear of the cover to make sure that side is not loose.

While twisting the still connected hose look at the back of the cover and see that the cover moves away from the belt because in effect pulling the cover toward the back of the car. There is no bolt or anything holding this section of the cover and if its warped due to heat or age this is the only way to fix it.

Look at the hex bolt on the pulley in the same area give yourself .5 mm of clearance and tighten the hose clamp you loosened earlier while holding the tension. Check it by sliding something behind the belt to make sure you have clearance. Run the car with the cover off to look for any other abnormalities.

Hope this helps

[fmartenies]

Except the timing belt is on the upper left, not the upper right. And if it is rubbing it will be between the tension pulley and the cam sprocket. Soooo put the pulleys and sprockets back in plane. The plastic cover is great otherwise you wouldn't hear the problem until you were ripping the belt on metal.

[mikepellegrini]

My kid had that problem on his 951. It was rubbing the case right under the cam gear, on top.

What he found was that the case wasn't quite tightened down - the top bolt hole didn't precisely match the hole in the block, so the PO had left off that bolt.

Without taking off the belt, we were able to enlarge the hole in the case sufficiently so we were able to get a bolt in it. Tightened down properly, the rubbing stopped.

You verified the bolts are there, or that they're tight?

[LUFTMAN]

is there a flat washer behind cam belt tensioner? if not put one and try it to see if that fixes your problem . early 944 models had a washer there. regards tom

[fmartenies]

I have an early 944 and there was not a washer there when I got it...never saw one behind in the fiche, just in front. Regardless, there is now. No more rubbing and whining.

[Gary2397]

I put a flat washer behind the cam belt tensioner. The belt noise still there even though
the belt got clearance. I sprayed STP all serpentine belt usage on the cam belt and balance shaft belt to get rid of corossion and fiction.

Now, it runs better. I will drive the way it is due to the belt had less than 10K miles.
_____________________
1983 944

[John_AZ]

Great seeing "SoCal Driver" posts.

John