afenton

Hi - I've got an '84 944 NA that my brothers and I purchased from a used car salesman in 1994. We noticed a few years down the road that the #4 spark plug/socket had been cross-threaded. Tried chasing it ourselves but weren't happy with the job and ended up taking it to a shop for a more professional fix.

Since then I've been careful with that socket, but have still been able to torque it and everything.

This weekend while taking off from a red light (like normal -- wasn't pushing it), the #4 plug popped out. Went to the local Advance Auto store and got a 14mm thread chaser. It's not really sticking in there at all. I tried using the chaser on one of the other sockets and it seemed to work like it should, so I think that ruled out the wrong size chaser.

So any suggestions for what to do from here? Not sure what my options are -- whether it should be possible to chase the threads, or maybe I'm using the wrong size chaser, or if I'm looking at something more drastic.

Thanks for your help!

Adam
'84 944 NA

931guru

There is a repair kit for spark plug holes called a TimeSert. Have your mechanic rethread the hole using this system. Should cost you about $100. Lifetime fix.

Rock

Worse case you get an N/a head and bolt it on there.

Be careful you dont want aluminum shreads in the combustion chamber.

AR10

The TimeSert method is the way to go! I have used it to repair all kinds of stripped bolt and spark plug holes. You should be able to buy a kit to do spark plug holes for about $50 and do it yourself.
Use grease on the tools to keep most of the aluminum from falling in. A few pieces in there will not
hurt anything, they will blow out through the exhaust valve.

Mark-87-951

slightly off-topic but will that timesert work for an intake manifold bolt hole that appears to be stripped?

AR10

Yes

FRporscheman

A friend of mine just had this happen to his 968. It was also the #4 plug hole. He took it to a mechanic, and the mechanic charged him like $300 to do a Helicoil. That mechanic said timesert is no good for aluminum and that helicoil is better. I think that guy is a jerk and charges too much for so-so work, but apparently the helicoil works too because my friend's 968 has been running well for thousands of miles now.

Mike Murphy

Wow, I did not know about the TimeSert and was going to suggest getting a new head. I'd be interested to learn if this TimeSert really does work well or not. My feeling is that you need to retain the exact shape and size of the combustion chamber, so anything that affect those two things is not good.

FRporscheman

The timesert (and helicoil) are just thread inserts that reduce the size of a hole. When a 8mm hole gets stripped, you drill it to 9mm and tap it. Then you stick in the insert and now you have a 8mm hole again. It doesn't change anything's shape or function at all. Except, reportedly helicoil can't take too much torquing.

TF

I also had the helicoil done on #4 worked fine, didn't cost $300 I think $50

AR10

Helicoil works ok, but I like the Timesert because it is less likely to come out with the plug when you are replacing them. It is a steel insert with a collar on top that allows you to tighten it in place.
Highly recommended!

FRporscheman

Yeah I also think timesert is better but they both work. And yes, a repair like this should not cost $300.

marky522

Timesert is the Porsche fix, we have a kit for doing all sorts of different repairs. We have a 996 running around this area with both caliper bolts on the passenger side helicoiled, but they both took factory torque, and did not loosen up.

Mark