Dannyp

Help my 84 944na is throwing belts right and left.
The alt/ac belt ive replaced 2 in about 3 weeks, and yes it was tight.
What the !@##@$#$%$%(* is going on?
Any help would be great.
Danny <img src="confused.gif" border="0">

Matt 86 951

Check the guides on all of the pullies. I think the tensioner is the one you really need to look at. The rib should be away from the engine, not closer to it. Ribs or Perry went through a similar problem, hopefully one of them will speak up.

Thaddeus

Though I've never experienced this on a Porsche, I've seen it on other cars. In the case of those, the rollers somehow got out of alignment such that the belt was not moving in a planiform way. Check the tension roller as per above, and make sure everything is lined up properly.

Thaddeus

Danno

Some of the rollers have guides only on one side. They should alternate back and forth along the belt's travel path.

The other thing it could be is that the protruding bolts for some of the idler pulleys may be bent. Like the tensioner and idler for the lower balance shaft.

instigator

guys i think he is talking about the belts not inside the timing cover, good theories though.

look very good at the alt/ac/crank pullies for bends or looseness

jim968

I'm pretty sure Instigator has pegged it; throwing belts is a sign of a bent or loose pulley, or maybe a bad bearing in the alt. or AC.

Danny, pull the belt off (I know, but it's the surest way) and try to wiggle each of the three pulleys on it's shaft (back to front & side to side) to check for a loose pulley. Then spin the alt & AC pulleys by hand. Watch for wobble (bent pulley), feel for roughness, listen for noise (bearing in alt or AC clutch). My guess is a loose crank pulley, but it could be any of the three.

Then as best you can from top & bottom, sight along the outer edge of each pulley to the next one; look for any misalignment from pulley to pulley (loose compressor or alt., busted bracket, etc.).

And that freakin' belt has to be _tight_! Expect to maybe need to re-tighten a new belt in a few hundred miles (this may be the source of your problem).

Jim, "Help stop inbreeding! Ban country music!" <img src="graemlins/nono.gif" border="0" alt="[nono]" />

Matt B.

My 86 944 na tore up 3 belts in 2 weeks right when i bought it. many people told me the pullys had to be not strait with eachother. it turned out after i turned it over to my local shop after say the 4th belt or so, that the ac compressor was freezeing up and makeing it chew the belt off. it was a brand new looking sandon rotary compressor and cooled great. i got a new a/c compressor and it has never happened again. if you have the old belt look at it see if it was just thrown off from mis alignment or if it is glazed and burnt like mine was from the bearing locking up on either pully.

athens944

When i originally bought my car the PO or his "mechanic" had the tensioner on the altenator in the wrong hole. This will take you through altenator belts quicky. Look at the picture of the underside of the vehicle if you have a Haynes Manual. It shows the tensioner as it should be.

Hans

They should last longer.
One of the belts in mine (power steering pump) shows it is made by Porsche!!!
My best guess is that it is still OEM. (Porsche dealers in NL know where to get V-belts for normal prices).

Corrosion or damage on one of the pulley flanges will kill a belt as well.
Check the thrown belt for signs of were (glazing) or damage like cutting marks / rough or worn side walls.
Glazing indicates transmission problems like blocked bearings (over load of the belt), rough walls indicate an alighnment / corrosion / damage problem.
Take Care