teke951

Hey all,
Hopefully, someone can answer this and easy my fears. I've got an '87 951 I bought 7 months ago. When I bought it, I had everything inspected and what didn't look alright, I replaced. My main concern was the timing belt. The Porsche mechanic said that it looked good to him at the time. The previous owner said last time it was changed was 20,000 miles ago. Well, a friend of mine who used to own a 951 said that his timing belt would go every 20-25,000 miles. So now, 7 months later, and only 2,500 miles added on (its only a weekend car and autox a few times) I'm thinking my 951 will have the same fate as my friends soon. Am I over concerned or has anyone else had experiences with timing belts going so quickly. Should their be anything to look out for or inspect, or any sounds I should listen for. Thanx for the input.
BTW - I am new to the Rennlist forum and damn glad to be here. Since I've bought my 951, I don't think driven a more fun car.

christian

There is an interesting article in excellence August 94. Current status is to change the belts at 45,000 or 60,000 miles following the servicing technicians discretion (earlier if you use your car on the track). They always should be checked each 15,000 miles. The major problem seem to occur when the belts have not been tensioned properly and checked with a special tool P9201 (about USD 500). This should even be done on the newer engines (starting 1987) although they are not that big of a problem as they do have the self tensioner (but they can fail). If the previous owner has no records for the belts then I would assume that they haven't been changed or tensioned properly. Have them changed asap by an OPC with the proper tools. Don't forget to have the accessory belt changed as well as it drives the water pump and a water pump replacement is major labor intensive work.

tecart

on my 1986, it has no self adjusting tensioner, so i replace all my belts every 15,000 miles and retension the timing and balance shaft belts 2,000 miles afterwards, usually the timing belt is a little loose at this point, after that i run the car without worry, i chang mine often but i dont want a bent valve, because i run the car hard but if you dont boost past 17 psi often then 25,000 miles replacment should be done for all belts

adrial

35k miles is fine for timing and balance belts..

15k is excessive IMO, as is 25k.

What does boost have to do with belt life??

None of them have a tensioner that adjusts as you drive, the 87 and laters that have the auto-tensioner requires that a bolt be loosened...then the tensioner sets the tension...then you tighten the bolt and put it back together.

After you change it, it should be tensioned 1500 miles later and many suggest retensioning after another 15k.

951carter

The water pump is driven by the back of the timing belt, not the accessory belt.

I reccommend changing @ 30,000 and retension @ 2,000

This also depends greatly on age. I would not want to run on an old belt even if it had little mileage

jason952

Do you know the age of the belt? If less than 4-5 years you may be good for 10k or so more miles. Or you could change it and not worry. I am personally sticking with changing at ~30k or 3yrs. I doubt even the best mechanic can look at a belt and say it's ok, v-belts maybe but the uncertainty is there.

Jason

teke951

Thanks to all who responded. Since the belts were replaced about 3 years, 22,000 miles ago, and I have no record of when the water pump was replaced, I'll probably go ahead and get it all replaced. It will put my mind at ease at least.