scotsman60

All,

This thread is a continuation of a previous thread entitled "Pinging". I've started a new thread because of a significant change in the problem since I first posted about the pinging problem.

The story so far......

After increasing the octane rating of the gas I use by mixing premium with race gas my pinging problem went away. I then started to hear a new noise which I suspected was arcing in the high tension system.

In preparation for an investigation tonight - in the dark with a water mister - I thought I'd quickly check for distributor belt slippage - no problem there.

I then started to check the plugs to make sure they were all tight and properly connected. While I was fishing around in the plug recess on the inlet side of number 3 cylinder I felt something loose. To my horror it turned out to be a broken head stud!!!!

I now suspect that the noise I've been hearing since the pinging went away was in fact leakage between the cylinder head and the cylinder and not arcing.

So I'm now looking at a substantial amount of work. My initial thoughts are that at the very least I'll have to remove the engine and strip the left bank off. I'm thinking that I should be able to remove the cam towers and heads as a single unit, pull out the cylinders, extract the broken stud, replace it and re-assemble.

Does this seem reasonable?

Should I replace all studs and if so why?

Should I do both banks? (Of course I'll check that I don't have any more broken studs)

Since I'll have the cylinders out I'll be able to check the rings and valves for detonation induced damage.


I'm planning on modifying this car with a new (used) twin turbo engine next year so I'm not motivated to do a full engine tear down and recondition at this time......





Doug

Wachuko

Same situation occurred to my car a few days after I purchased the car.... I was doing the valve adjustment, changing oil hoses, etc... preventive maintenance... when I heard a loud 'POP' from the right side of the engine. I used the car for another 8k miles (taking it easy) before I decided to take the plunge and have the car repaired by the Porsche dealer.

Total bill (parts and labor) came to around US$6,000.00. This included all studs (yes go ahead and replace them all... best to go with Raceware or ARP), all seals/rings/gaskets, new clutch/bearing/pressure plate, two tires, brake pads, brake fluid replaced, transmission oil replaced, spark plugs, wheel alignment.

Wachuko

Forgot to include that you should consider updating the guide tube and release fork. In my case that was already done (along with the flywheel) by the PO.