Tom R.

Not satisfied that Porsche doesn't publish a scheduled maintenance/replacement for the cam chain tensioner/tensioner ramp, I posted a question on the 928 board hoping there was a schedule for the 928. No luck yet.

I called a local Porsche dealer for a price on the part ($316 to a street customer). The parts salesman gave me the name of a reputable shop the happens to advertise in the local PCNA magazine.

I called the shop, and the mechanic there was very helpful on the phone.

He said that if you replace, you replace the whole thing.

More importantly, he doesn't recommend opening the motor unless there is noise coming from the cam. He offered to put a stethoscope to my motor to see if all sounds OK. From what I gathered, the chain will start to slap around as the tensioner wears.

I guess the stethoscope is the most definitive answer so far.

Doesn't that suck in a way? The cost of replacing the part is high, the cost of a broken part is higher, and the most logical preventative maintenace is simply a good listen.

rpm's S2

Replaced my tensioner pad several months ago with little fuss. I did have the assistance of a friend who is an experienced mechanic - though my S2 is his first foray into Porsche. This site was invaluable:

Cam Tensioner Replacement

along with a thread from last August titled Cam Tensioner - plastic ramp (you can find it with the search function)
Good Luck!

Michael Stephenson

If you look at the picture from the above Cam Chain Tensioner link, you will notice that the pad broke as it was being removed. It is my understanding that pad breakage is the most common form of failure.

While I see how a stethoscope can help diagnose the condition of the chain / cams interface, I do not see how a stethoscope would be able to detect a faulty pad.

Personally, I like to look at the whole shebang at least once a year. I do a few DE events and the last thing I want is a tensioner failure. A visual inspection just makes me feel better. However, I do pay the price of very slight oil leakage around the cam cover, even when I replace the gasket.

------------------------

While we are on the subject, does anyone know the type of plastic used in the tensioner? It seems that it would not be to hard to fashion a bottom tensioner pad. Come to think of it, I might take a new top pad and try just such a thing…

jim968

Michael.. WRT your slight oil leakage: I dunno about the S2, but my 968 had a tiny amount of sealant at the corners of the head, apparently from the factory.

While I had the cam cover off to check the Variocam mechanism, I noticed a trace amount of white sealant on the head side of the surface that the gasket seals against. I wiped it off & put a dab of blue RTV in the same spot, then spread it with my finger tip.
It runs about 3/4" out from the corner, along both the side and end sealing surfaces of the head, and is thickest in the corner.

No leaks so far. Also no clue as to what this may do to the gasket when I pull it again...

I'm guessing from appearance that the ramp is nylon, but I'm not at all sure. If someone has a broken one they want to sacrifice, I'll look up the ID characteristics (simple DIY tests), tho' the oil saturation may blur the results. Do I recall correctly that a new one is more-or-less milky white?

Jim, noting that a "dab" is a metric unit of precision volume measurement, and slightly larger then a "smidgen" but much less than a "dollop."

rpm's S2

I have been pleasantly surprised that I have not had any leakage. I did replace the gasket. My next adventure is motor mounts

Riff

Michael-

About the 928's, AFAIK all the 32V cars used the same cam chain tensioner system, I'll double check the PN with PET tonight. My buddy has it in his '89 GT, but for some reason, the 928 does not suffer the same failure or at least there are very few reported failures which I find odd since the 928 had 4V per cylinder back in the mid/late 80's.

For building you're own replacement pads, that is a possibilty. I would think that the pads are a form of Nylon for the tuffness, but I could be way off. It would be pretty easy to get the material analysed, then all you'd have to do is create a plastic inj. mold tool, prolly run about $800, then the cost of running a small batch.

I remember that someone in the past replaced the plastic pads with brass, but I think that would be a bad idea. The ramps act as a sacrificial piece, you strengthen the pad then something else becomes the wear item (the chain!) in the system and I would rather replace the tensioner than the chain anyday.

Cheers

jim3

The 944S plastic pad and chain tensioner are available under a single part no from Porsche for the big $. But as I understand it the 928 pad is the same part and is available without the whole tensioner. Zims sells the pad alone for under $30. Conservative PM says change pad at 60k miles. If you've got more than a 100k miles conservative PM says change the chain as it does stretch. For any one new to 16 valve motor, it's not if it will fail, but when. The S list always had someone bemoaning a failure. Then it's really expensive!!!

Roy LaZelle

I pulled the valve cover on my 89 S2 and checked the tensioner pad. I could just catch a fingernail in the wear groves. My take is the PO must have replaced the tensioner and pad. My currnet plan is to check for wear yearly. --Roy--

Tom

According to my Parts and Technical Reference catalog, the 928 uses a different tensioner PN for each bank of cylinders while the 944S uses a 944 PN tensioner. I can't think of why there should be differences other than to make life more complicated but apparently the differences are there. I don't know whether this would mean that 928s can't use the tensioner pad.

Crackhead944S

I changed the tensioner in my car. I bought the entire part, pads and all from Paragon @ about $280. I think, both the top and bottom pads' part numbers started with 928. I'm also, fairly certain that the old pads also started with 928, but I'll check and post it if I can find the old part.

BTW, the only leak I got from removing the valve cover three times(some of you might remember the stripped tensioner bolt and Heli-coil story) is a small one from one of rubber grommets around a bolt that holds the cover on. And I reused the old gasket.

Mark
'88 944S

John 944S2

The tensioner pads are a 928 part and can be purchased from a Porsche main dealer.

I got mine in the UK for £2 (about $3).

I have a thread here somewhere which quotes the full 928 part number which was identifical to the one I removed from my S2.

I replaced mine at 80K and it showed very little wear.

John

Tom R.

Ok, lets try to get a general consensus here.

The $3 pads are cheap, and for preventative maintenance change them at 70K, even if the chain sounds good using a stethoscope.

If the motor is open/valve work is being done then change the whole hydraulic tensioner assembly (and chain) or change at ??? miles whichever comes first.

How's that sound?

Now the tuff part, what's the difference between the Zim's $30 part, and the Porsche dealer's $3 part?


Also, I don't know how to post a link to the other threemposts on this topic (2 on 944 board, 1 (mine) on 928 board) here. Could we make this a solid thread by adding the links.

Thanks again.

Crackhead944S

OK, I finally found my old part. The number on the top pad is 928.105.509.01 and the number on the bottom pad is 928.105.347.01. I called two dealerships and the price quotes for just the bottom tensioner pad were $297.00 and $340.00. Thank you paragon for the entire assembly for $280.00. I know I could have got the top pad for $25.00, but is someone going to make a bottom pad or can one get it from the UK for three bucks?

BTW for those considering an “S” verse a regular NA, this was changed in under two hours by myself, the mechanically declined.

Mark
’88 944S and loving it

AndyK

Hey Crackhead-

I would love to see a step-by-step on how you changed out the pads in under 2 hours! I am mechanically de-clined, and would never think of messing with a vital engine part--unless it was relatively easy.

Jeff928S4

So 944S, did you change the entire Tensioner or just the pads?? I have a S and know that the J-tube that supplies the oil to the Tensioner should all be replaced (basically the whole unit).

When checking the Pads, did you just simply remove the Valve cover and look in?? You didn't have to move anything else did ya??

My S has about 75,000 miles - should I start checking now??? Am I safe for a bit or am I in the danger area??