John 944S2

Need some advice here.

I have recently had new timing and balance belts fitted to my 944S2 by an Official Porsche Centre. I have noticed rubber deposits on the upper cam idler gear, which I guess is coming from the new cam belt. The belts have been re-tensioned after 2K miles as per normal procedure. The belts still whine and I want to know if:-

a)anyone believes whining belts are normal after 3K miles

b)anyone seen this rubber deposit before (i.e. is it just because the belts are new)

My personal opinion is that the belts are too tight, they do get hot after a long run but this may be from the engine.

Any thoughts before I go back to the OPC.

Thanks

John

jim968

FWIW, I'm 99% sure that the cam belt on an S2 has an automatic tensioner, and does not require retensioning, other than maybe as a check of proper functioning of the tensioner.

Yes, if it's still whining, a belt is too tight; probably the balance shaft belt, which is manually tensioned. This 'un needs _very_ little tension, since it transmits almost no power, compared to the cam belt. I DIY'd mine (968) three times w/o the gauge; either it was scary loose, or it was whining. I finally had my wrench do it with the magic tool, and it was quiet, and _almost_ scary loose.

Not a clue as the source of rubber deposits, unless the belt has oil on it, softening the rubber????

Jim, "A person who is nice to you but rude to the waiter is not a nice person."

John 944S2

Thanks Jim for the comments.

You are right, it does have the automatic tensioner but I do notice a very slight deflection in the belt against the idler. This maybe normal !!

re: balance belts. yes these are very loose, so much so that you can spin the balance belt idler against the belt.

I can see a re-visit to the OPC on the way.

Cheers

Forrest

John -

I just had all belts/tension rollers/idler pulleys (and water pump, too) replaced on my '89S2 at 79k miles (last belt replace was at 40k miles). One of the idlers was squeaking good and the tech wanted to replace it before letting the car go out the shop. I went ahead and had it and everything else replaced as a preventative measure while the car was opened up (the belts were w/in approx. 5k miles of the replacement interval).

The S2 does not have an automatic tensioner. It should be adjusted at time of belt replacement and again after 2k or so more miles. (Porsche recommends belt replacement every 45k; cautious others recommend more frequent at every 30k; it is also prudent to have belt tension checked also at 15k mi intervals in addition to the above.) I think only the 968 has an hydraulic tensioner and does not need periodic adjustment (therefore belts can go as long as 60k before needing replacement). The reason the belts need replacement is because they stretch after time/use/heat/load/etc. The reason the belt tension needs checking periodically is because it is not self-adjusting.

As far as the squeal/whining on your car goes, one of the idler pulleys may also need replacement. Was the whine present before you had the belts replaced? If so, the tech probably should have caught the source of the noise. If you only had the belts replaced, it is conceivable it began to make noise afterwards.

I am assuming the rubber deposition is from the new belts (or particulates from the old belts).

Hope this helps. The belts/pulleys/etc. seem to be the only major expense/maintenance pain (oh, forgot the control arms!)

Next time you have the belts replaced, if car is above 75k miles, consider having water pump replaced at same time. Labor to replace belts is 5 hrs. Labor to replace water pump is 8 hrs if done separately (all the belts have to come off to get to.)

Ciao!
Forrest
'89 944S2 and having entirely too much fun with it.

MadMax

John,
I had all the belts, seals, tensioners, and water pump replaced at ~75K miles. The work was done by Brumos Porsche in Jacksonville, FL. There was no whine present before the service and there is one now. I had the belt tension checked/adjusted at the 1.5-2K interval and the belts still whine.

I asked both the Service Manager and the actual mechanic at Brumos if this noise was normal (mechanic is particularly fond of the 944, owned several himself over the years), and they both told me it was. Mechanic told me that sometimes, no matter what you do, you can't keep the balance belt from whining.

If they are BSing me then it would be the first time Brumos has ever done that.

IHTH,
Max

Michael Stephenson

The S2 has a tensioner for the belts, but it is not automatic. In theory, you loosen it and let it find the right tension then you tighten it back down. I am not sure of the exact procedure, but that is the gist of it. I have heard that it is still a good idea to verify the tension with “the tool”

I inspect my belts several times a year and each time I remove the cover I wipe off a thin film of black rubber dust, which I imagine is from the belts.

My belts do whine a bit. I do not really notice it unless the windows are down and I am passing close to something solid, like a retaining wall or a guardrail. If try to I hear it, I can hear it. It is my understanding that some whine is normal. However, what is “normal” is anybody’s guess.

John 944S2

Thanks for all the comments.

You are correct, I mistook the spring tensioner for the automatic tensioner. It appears that 968 owners are lucky.

The car has just completed 80K, the new belts (2nd set) being fitted at 78K. I had previously replaced all the idler gears at 50K and after checking they are still OK. Whining belts appears to vary from car to car, and if its generally the balance belts then I can live it with. It can only be heard with the windows open. I will watch the rubber deposits (small lumps of rubber stuck to the cam idler) and see if it gets worse.

I do get a vibration noise at 1.5-2K revs and have never been able to trace it, this is the reason I changed the idler gears (rollers). I wonder if this could be the water pump, its definitely from the front of the engine. It has never been replaced.

Any thoughts

thanks