Stripped thread in exhaust manifold
 

Did some searching but didn't find this specific problem addressed yet. Will keep looking but any input would be appreciated. The problem -

Discovered I had a missing nut and stud on my downpipe. Found that manifold thread for the stud is stripped at least half way down the blind hole, although there is some thread remaining at the bottom. The stripped portion actually looks to be greater diameter than the thread would have been - in other words it probably has a previous history of damage and maybe repair attempts. Any ideas on fixing it? (Yes, the turbos ARE out of the car).

Thanks

Dave

Remove the damaged stud and buy another. If the hole in the exhaust manifold is fubared use a Helicoil to repair it. I have 3 of them in my manifold right now. It's a permanent repair.

You're way ahead of the game since the turbos are already out.

DamonB -

Thanks for the reply.

The stud is already out - because, since I owned the car, it was never in! When I look at it, like I said, it looks like it was damaged a while ago. Currently, in the first half of the hole, there is no thread at all! Indeed, it almost looks like somebody tried to drill out the old stud and, as a result, enlarged the hole to a diameter greater than the original thread outer diameter, (and probably a little off-center), for at least half the depth of the thread.

I'm encouraged by your good experience with the Helicoils, but, given the above description, my question ref your response is, "in such a case, will the Helicoil still fix it?"

Thanks

Dave

Stripped exhaust manifold stud thread
 

Bump!

Anyone out there had experience of using a Heloicoil with a manifold thread damaged as I described in last post?

Thanks

Dave

Yes the helicoil is fine. Here is a link to some. You have to scroll down for the metrics.

http://www.toolsource.com/ost/result...FQkVHgod7ydvvw

i would try to use a tap and attempt to correct some treads... though if there are not threads i would yes then drill it and put a heli coil in there. take a picture so i know exactly what your talking about... though im quite sure. good luck :)

The fact that the threads are missing doesn't concern me at all, that just means it's stripped. Look closely at the hole. If the threads are merely gone I'm certain a Helicoil will be fine. If someone tried to drill it out the hole may already be too enlarged to fit the proper size Helicoil for that stud. If somebody made a huge hole with a drill then it's possible the hole is already to big to allow repair without going to a fatter stud.

I broke a thread in my manifold and found it easier to just buy a used manifold from somebody going to single turbo. There are plenty of those out there and they are cheap too.