nedkelly

Guys,

A while back I was gathering some info about doing the belts on my 92 tip coupe. Well the day finally arrived when I put the car into the shop. They stripped the front out to reveal the belts and then I got the dreaded phone call about everything else that need sto be done....oh no I thought!
Not too bad though in the end, only the pulleys were shot. The cam belt was looking a bit ropey but it does have 70,000 KM on it! I visited the shop to inspect the issues and was suprised to see there is no hydraulic tensioner in my engine. Only the mechanical tensioners like in the 944 I think (looking at the clarks-garage website). With my car being a 92 model maybe they were not fitted to this early model? Anyway just the belts and the idler pulley and the water pump[ pulley needs replacing. No play at all in the water pump and no tell tale signs of any leaks. Should have it back on the road in a few days with the smile well and truly back on my face. Anybody shed any light on the missing hydraulic tensioner?

Cheers,

BruceWard

It has been suggested that the hydraulic tensioner can be replaced with the tensioner from the S2. Some owners say they would prefer the S2 type. My hydraulic tensioner failed and I had to replace it. I considered the S2 route which I believe would have been less expensive but never having seen one I decided to go with the hydraulic version.

PorscheG96

What are the last 4 digits in your VIN # and the car's build date? Despite it being a '92 the engine should have come with a hydraulic timing belt tensioner from the factory. Bruce is suggesting that it may have been replaced with the 944 tensioner by a previous owner/mechanic...which is a possibility.

Alex Cook

I thought the 944s had automatic tensioners also (from about '87?)

RajDatta

Ned, I think the previous owner was like me and decided to swap it with the S2 part. Springs dont leak, hydraulic seals do as often witnessed. I would recommend the swap to anyone and would not go back to hydraulic tensioner even if I got a brand new one for free.
Ofcourse, normal disclaimers apply! .
Raj

nedkelly

Thanks Guys for your input.
Strange thing about my car though is that there is no spring tensioner either! On the front of the block there I cannot remember seeing any lugs or holes either to suggest one was ever fitted. Just the eccentric tensioners on the cam belt roller and balance belt roller. Looks like I've ended up with the genetic leftovers from yesteryears Porsches, oh no I must go back into the shop and check before it's all back together. Decided to have the brakes off whilst they have it and have them sand blasted, seals replaced and then repainted red with a good dose of clearcoat. Should take my mind of the tensioners!

RajDatta

Ned, can you post some pics. That is really the only way to know for sure what is going on. There has to be something there to tension teh timing belt. It is somewhat snug without the tensioner but i doubt it would have lasted this long without it.
Raj

nedkelly

Raj,
Take a look at www.clarks-garage.com, specifically ENG-10 procedure for cam belt tensioning. My set up looks just like the first one out of the three that are shown. Will get some pics hopefully today on the way home from this dreadfully long night shift *@#%^!
Thanks.

RajDatta

Ned, that would be the cheapest way to do it and that is the only reason I can see someone going to that setup. It requires the P9201 tool to perform the task.
Chances are they had problems with the hydraulic tensioner and decided to use the cheapest method to be able to tension again.
Raj

nedkelly

Raj,
I agree that it is the cheapest/less complex setup. I was shocked to see it though as the car was serviced every 3000KM by porsche OPC in Japan. I would be surprised to hear that OPC had changed the setup. Also, like I said earlier, I cannot remember seeing any holes or lugs present for any type of tensioner to be fitted. I am not losing any sleep over the issue but as I am brand new to this marque it is nice to learn a little bit more about them and their quirks.

BruceWard

Ned, if you can take some pictures but need a place to host them email them to me. I would love to see what you have.

RajDatta

Ned, there is usually a stud that is connected to the block and the tensioner arm swivels on this stud. There are bunch of washers involved as well. I do have a complete setup if you want to retrofit. I would recommend against the hydraulic tensioner but if you want to try the original setup without spending close to $500, let me know.
Raj

nedkelly

Okay fellas,
Pictures hopefully in the next 24 hrs. Bruce, thanks for the offer for posting the pics, will email them as soon as I have downloaded on to my PC. Raj, what do you feel the benefits would be retro fitting the spring tensioner setup? The obvious that springs to mind (pun intended) is that if the eccentric adjusters slip then maybe the spring tensioner will take up enough of the slack to prevent the belt coming off completely and to take up slack due to belt stretch over time.
Thanks fellas.

BruceWard

Ned, I believe the spring type tensioner is much less likely to fail. I inspected my belts in December I found the belts to be in excellent condition but the tensioner had lost its filler. I had a $5k belt failure on the way!

If I had the experience to understand how to do so I probably would have fitted the spring tensioner. But not ever having seen the S2 version I decided to replace the hydraulic tensioner, this also removed the concern about correctly tensioning the timing belt. I believe the main advantage of the hydraulic tensioner is the lack of need to set the tension on the timing belt.

RajDatta

I 2nd that. The 968 tensioner is designed to be constantly tensioning with hydraulic pressure. It is a "dynamic" tensioner unlike the S2, where you set it to preload according to the spring and then tighten the mechanism. Even with that setup, all you do is unload the tensioner and let it spring tension back on the timing belt and then retighten it. I will have some pics for you this weekend.
So, that is pretty much it. 968 tensioners will always tension at all given loads but are hydraulic and can fail where as S2 tensioners are spring loaded and will provide static tension.
Hope that clears a few things.