Replacing cam chain tensioners...
 

I am thinking about replacing the cam chain tensioners to the spring loaded style on my car as a bit of preventative maintenance. I have a 97 boxster with 120K and as far as I know it's got the original ones.

When it's cold it makes a pretty noticeable rattle on start up, especially if it's under 40 degrees outside. In the summer, it only does it when it has been sitting for a few days. I did some searching on the forum, asked my mechanic and it sounds like a normal thing, but I really hate it and I am afraid that it will will the motor.

I looked at the instructions on Pelican Parts and it looks pretty straight forward. The only thing that I don't have is the P253 tool to lock the cams. Do I need to lock the cams to replace the external tensioners? Has any one DIY'ed this one and have some tips to share?

Thanks,

Reed

I replaced mine several months ago on my '98. One of the questions that comes up again and again is, "do I have to lock the cams". The answer that I have seen most is that if you lock the crank at top dead center and replace one tensioner at a time, you may be able to complete the repair without consequence. But, not everyone gets lucky, and there is the possibility that the chain could skip a tooth. It is my understanding that early boxsters with double row IMS bearings have more chain tension and are less likely to skip time. I rolled the dice and won. If doing it again, I think I would purchase the tool kit from ln for doing the IMS bearing. It includes the cam locking tool along with the other specialty tools needed for replacing the IMS bearing, yet costs about the same or less than the Sir P253. Since I plan to replace the IMS sometime in the future, it may have made sense to have purchased the kit when doing the tensioners. In retrospect, it was probably foolish to risk an engine over the cost of a $200 tool.

I wish I would have known to purchase the updated tensioners with the external spring. My engine still has start-up rattle even after replacing the tensioners....bummer