Club1320

What is the round about price to have a shop tighten the tension of the timing belt in the 32 valve 928? (86.5) to be exact.

When i purchased the 928 recently the p/o told me that the light coming on now and again is normal. Obviously this guy should know better. I have done alot of research about these on here. My tension light only seems to come on if you redline any one of the gears. Normal driving causes no prob. Therefore i drive normal, if i drive it at all.

Being that i just purchased this car, i have many things to work out, so i am going down the list one at a time.

Chris.

joejoe

If not known when belt was last changed then do it. I spun the belt off mine (also 86.5) on start up. No warning light. I pulled the motor myself and was lucky only two valves were bent. Cost of this mistake was about $4,000 (I did do quite a bit missed maintainance also)

If you have the tool you can check yourself. It takes some disassembly of passenger side rotor and cover. When there condition of belt can also be done. Do this with engine cold for correct reading. Not sure what cost at shop would be as places charge different rates. If shop not experienced with 928 expect more I think (also expect them to find a multitude of things that need replacement) Before I started doing own work I would usually have to fix things shop had broken when repairing something. Hope this helps some.

SeanR

If they know what they are doing, it will be an hours of labor for 30 minutes of work. As said, be sure when the belt was last changed.

Landseer

Why don't you, for the heck of it, post a picture of the timing belt tracking?

Just pull off the passenger side intake tube and shoot a picture straight down into the timing cover vent hole on that side. Might need to do it in sunlight, else have somebody shine a light down in there.

GlenL

Not "normal" but certainly not "unusual."

Get the aftermarket "Kempf" tool and do it yourself. Might take two hours but you'll have $100 in your pocket. OK. $50 and a new, cool tool.

If that's not yer style, get strong references for a local shop. Don't do the dealer.

Mrmerlin

note the timing belt tension must be checked with the engine cold and at TDC make sure to check that the cam timing marks are both lined up

Landseer

^^^^ +1, what Glen & Stan said. You can get a good read on the situation by pulling the cover off.

danglerb

If they don't know the 928 and screw up, $2k to $5k depending on how the system fails later on.

Sad to say I don't think in general you can put any trust into work done by or for a previous owner, unless its a known good 928 mechanic.

Find a good 928 mechanic and have them look it over carefully, making sure the tensioner is full of oil and was rebuilt, that all the gears are in good shape and that the belt is tracking well.

James Bailey

It is NEVER a good idea to just tighten the belt....NEVER ! You need to KNOW if anything else is happening that would cause the belt to be loose. It is possible that the belt was never as tight as it should be or the tensioner has no oil in it or a none OEM belt was used or the tensioner arm bolt is bending or any number of other things. However for peace of mind you might just consider replacing the belt etc. and enjoy driving your car !

Club1320

I have a receipt for the timing belt being changed from the owner before last. I will have to look again but its less then 20,000 miles ago. As i have stated in other posts. The owner i bought it from did not seem to know what he was purchasing. Just think he liked saying he had a porsche. The guy before him was a 928 oc member and kept amazing records of service. So i basically got a good 928 with a lack of maintenance recently. Like i said, i am going thru the list of things i was told about 1 at a time to get it all sorted. Thanks for the heads up and ill get a pick posted up as soon as possible.

M. Requin

Listen to Mr Bailey. I would only add, based on what you have related, that if the receipt for the TB change is dated right before the sale to the PO, then itmight just be that the belt was never properly retensioned. In other words, belt replaced, car sold immediately, new owner (your PO) did not know/just didn't care - whatever - that the belt needed to be retensioned, and didn't. That does not mean that a simple retensioning will solve the problem.

Club1320

Good point, although alot of work was done at the same time as timing belt. The water pump replaced, shortblock rebuilt, trans service, radiator replaced all radiator hoses, all new belts. etc.

blown 87

I agree

PorKen

There could always be other issues, but a high rpm trigger is often caused by a loss of oil in the tensioner.

Landseer

I think original undertensioning, ie, less than 1/2 window on a 32V car, is a possible reason.

Combined with a little belt stretch....

Mine had oil (another reason if low), but I improperly tensioned them originally.
Did something similar to Cpayne's car a few weeks ago, too, that we've now solved via proper tensioning.

Then again, I'd have to pull the crank cover off and peruse the whole system on a new acquisition. Unless one of you guys looked me in the eye and told me exactly what you replaced in the system.