Porsche Enthusiasts Club Forum

I am now well on the way to re-newing the timing belts, before I finish I want to check the condition of the chain and adjuster. There doesnt seem to be much clearance under the two fuel lines that cross the cam cover towards the back of the engine. Will the cover come off without removing these pipes or lifting the injector rail?
BTW I have measured the tension of the balance belt using a spring balance and ruler on the longest run and will set the new belt to that tension, unless someone can lend me the proper tool.
Bruce

Hi Bruce,

Looking at this picture:

http://boerger.golden-tech.com/camshafts.jpg

it does look possible.

Hi i have just changed my cam chain slipper pads and it does come off without removing fuel pipes
You have to remove the rocker cover bolts completely they screw out so far then can be pulled out complete with rubber grommet, theres a 10mm bolt at the back holding clutch pipe to remove, and thats it just wiggle cover free

Thanks for the replies and advice. That part of the job has been put back a touch as I had massive problems undoing the crankshaft pulley bolt. a 3/4 drive knuckle bar plus 4 ft of pipe did it oin the end.
Bruce

Out of interest, how do you intend to check those cam sprockets and the chain? Just by eyeballing them, or by doing some measurement?


Oli.

HI,
Your question prompted me to look at the car's service history. The belts and pulleys were changed at 105K but that was 4 1/2 years ago, hence the belt change now. The chain was also replaced as was the upper tensioner slipper, but not the lower slipper. This is all on paperwork from Hartech, a note from the then owner says the chain tensioner was also replaced. The car has now done 122K so now I don't know whether to check it or not. Advice please.
Bruce

There is no hard and fast rule regarding the chain and tensioner for the 16V models and Porsche have to this day never published a maintenance guideline. When I first bought my S2 in 1998 at 90,000 miles we were just starting to hear of a few chain failures as cars approached 10 years old. I had my chain and slipper changed at the very next service and everything was reported to be fine. I had it changed again at 150k miles just to be safe and this year it will be approaching 200k miles so I will have it changed again.

The trouble is you cannot easily see if any wear is occuring to the chain or sprockets, and most of the work involved to inspect it is the same as having it changed so I prefer to err on the side of caution and stump up a few hundred quid every 5 years or so for peace of mind.

Really? What's involved in inspecting it?

Changing it is a big job - it will be removal of the belts as well as removal of the cams to get the chain out (assuming the chain doesn't split). Inspecting it must be easier than this, surely?


Oli.

There is no hard and fast rule regarding the chain and tensioner for the 16V models and Porsche have to this day never published a maintenance guideline.

I think this is why porsche made the slipper pads so simple to change, after all chain is probably the strongest drive device known to man
If they are tensioned properly they last thousands of miles. How often do you hear of BMWs snapping chains i know they do but only after starship miles
Porsche probably use the same sort of chain (german) When a friend of mine changed his 944 chain recently it had not stretched a mm it was exactly the same length as the new one
In my experience (life long biker) if you keep a chain tensioned properly sprockets especially last longer also

Took the car out yesterday evening, wonderful, big smile etc etc, well worth all the hassle.
I did not check the chain and sprokets because I could not undo the socket cap screws holding down the cam cover. I almost rounded one off and decided to check with Hartech ( see earlier). Very helpful, the guy I spoke to looked up the cars history and said that after 17000 miles in 5 years it really wouldnt be worth the effort.
He also said that the chain rarely wears, its the teeth on the sprockets that causes the problems. The sprockets as they are part of the cam shaft are not hardened in the same way as motorbike or other drive sprockets, also the profile is a compromise as the sprockets are not really a large enough diameter. As the teeth wear the rollers hit the tips of the teeth instead of going down into the hollow between, eventually one or more tips break off. He said that some go straight down into the sump and no problems occur, others get caught in the chain and boing! you are in trouble. He also said that the factory recognised the problem and later cam shfts have different profile sprockets. How much is good info and how much is not I dont know, being an Essex bloke I have never had dealings with Hartech before now.

Bruce