[MB968]

So, help me out here. I've looked at a lot of posted info on these pads. As far as I can tell mine look good. I used a depth mic to measure the amount that the link is above the groove in the pads and subtraced that info form the actual width of the link. Looks like my tracks are about .65 mm., which according to what I read should be OK since it is less than 1 mm.



Out of curiosity, I also measured the amount that the rollers on the chain are below the edges of the link. According to this measurement the tracks would have to be on the order of 1.35 mm deep before the rollers would actually contact the pads. All the pictures of worn out pads showed fairly heavy tracks from the rollers in addition to the tracks from the links of the chain. So, for these worn pads the penetration of the links into the pads must have been deeper than the 1.35 mm. So, it seems to me that the "less than 1 mm" on the very safe side.



Since I'm brand new to the Porsche community, guess I'd just like to get some dialog/confirmation on my conclusions.

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[Cloud9...68]

How did you get a look at the bottom bad? I understand it's very difficult (or next to impossible) to see without taking the cams out. For some reason, the bottom pad tends to wear faster. Do you have any records as to when the pads were last changed? Their service life varies greatly, but some have been known to go a very long time.

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[Langley968]

I plan to change mine this winter, since I hear that even though they may not be worn, seing that they are made of "plastic", they tend to get brittle with age and have been know to shatter. Correct me if I'm wrong....

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[Scott Collins]

It's true that they will become "brittle" with age and use. They tend to get pitted where they chain makes contact. So it's tough to see that until you get them off. Both my upper and lower pads were pitted and worn when they were removed, and I had the pads and chain replaced at the same time.

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[Cloud9...68]

Yeah, this is one of those things that if you have any doubt, you should probably go ahead and replace them. However, be aware that it is a very big job - the cams have to come out, which means they have to be timed, which is a tricky procedure that not many people in the country know how to do.



Check the repair history of your car carefully. I went ahead and replaced mine soon after I got my car, and was amazed to find that the old ones looked brand new. Later, much to my dismay, I found a receipt indicating that they had been replaced not long before I had them done, so I wasted a lot of money.

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[ds968]

" the cams have to come out, which means they have to be timed, which is a tricky procedure that not many people in the country know how to do."



this is very true, the slightest variance in setting that timing can translate to material loss of hp ( I was told that a - 15 to 20 hp deviation can easily happen absent a "surgical precision" ideal setting ) so it may help to have a 968 expert who has done the job once ot twice successfully, guide you or your mechanic on the phone while the timing is set. just a suggestion.

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[Cloud9...68]

Dan is right. The challenge is going to be finding such a person.

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[DaveN]

I changed mine this year during the rebuild for the SC. I thought my top pad had very little wear so all wasn't too bad but when were removed the cam chain the bottom was worn a lot; don't go by the top one. And yes they get brittle with age and start to leave chunks floating around your cam <img src="/forum/images/smilies/968/sad.png" class="smilie" alt="" />

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