Porsche 911SC Maintenance

Have this little 911SC towed into the shop as it was not running, along for a few maintenance items like turn signal switch, a high idle issue (when it was running), and a few other minor odds and ends.

The airbox had recently been replaced at another non local shop because it blew up with no pop off valve installed, but when they installed the new box and installed a pop off valve, it was not done with the correct epoxy, hence a backfire and it popped out again, thus the non running car. I reinstalled with some proper epoxy and solved that issue. The next issue was the high idle issue. The air/fuel mixture was way off, and it took me a while to figure out why. The cold start system was not working properly, so someone had richened up the mixture so high to get it to start, that when running, then it had a high idle. With the mixture off so far, my guess is the car backfired big a couple times and cracked the airbox. I finally found a burnt wiring harness at the starter for the cold start valve system, so I rebuilt a stand alone harness for that circuit, along with replacing the cold start valve and the thermo time switch. This should allow us to properly set the air fuel mixture which should take care of our high idle.


A few minor oil leaks, but nothing major.

Customer had a set of weltmeister hydrastops that he wanted installed on the mechanical chain tensioners. I win some and I lose some (not very often) on items like this on occasion, but I do I feel the proper update is to the porsche hydraulic tensioner system as installed on the later cars. It isn’t cheap, but it is the right direction to take. The hydrastops install on the tensioners and act as a stop so when the tensioners fail, they can only collapse so far. The downside of these pieces is that you have to inspect and adjust the height every 15k miles, so in the long run you aren’t saving anything over the hydraulic chain tensioner update.

More from the Blog

Leave a Reply

Your email address will not be published. Required fields are marked *