need to repair a exhaust stud

[Ron Broman]

I have a spare engine I'm assembling to install in my 1970 911T. The problem was noticed as I began installing the heat exchangers. The exhaust port on number 6, along with several others, is missing the stud. The outside stud hole is tapered - obviously the object of several different studs, bolts or what ever!
That's the problem. I need some expert help on the best way to fix this short of tearing the engine apart and replacing the head.
I bought this engine to use while I am rebuilding/modifying the original engine. I was going to try JB weld, but don't know if I can get enough threads to catch and keep the stud perpendicular to the head. How about time-certs? Being a Porsche newbie I need to get some opinions. Thanks for all advice.

rbroman@cox.net

[Ron Broman]

Bump! I bought this engine as a long block- took all the accessories off the original and assembling them on the new/old longblock

ron

[john walker's workshop]

if there's enough meat left, a timesert may work. there are thick wall inserts also, like a 8mm vw case stud repair insert. 12mm threads i think. just have to get it centered, and in deep enough. cut off the excess sticking out, and you're in business. it's always a challenge.

[Wayne 962]

I doubt the JB would work, as these get super-hot. Try the inserts - I have seen a lot of heads with them in them work fine...

-Wayne

[HawgRyder]

Another possibility is a stepped stud.
This is a stud that has one end larger than the other.
I have used 8mm/10mm studs in VW engines in the past to fix this exact problem.
Just be careful to get it centred...and get the step all the way down to the surface so that the header seats.
Bob