I stripped one of the bolts on my UIM. I chased the threads clean w/ proper tap but it wont grab the bolt.. it threads in but gets to the bottom and spins. Can I just spin in a helicoil thread section, or do you have to use a special tap?

 

I've had a Helicoil in my exhaust manifold since 9/11/01.

No problems yet. Figure that the exhaust manifold is a much harsher environment than the intake.

Buy the helicoil you need, drill the UIM out to the diameter it calls out and thread it in. Simple.

 

you have to drill it larger in order to fit a helicoil for the stock size bolt. just make sure you drill straight its pretty easy to go off at an angle in aluminum. get a kit that comes with the proper tap and the insertion tool.

 

And be very careful that the drilled hole is as small as the drill size can make it. In aluminum, it's easy to make the hole a little too big if you're sloppy and then the helicoil won't fit tightly.

Dave

 

Helicoils work perfectly when correctly installed as others have stated. The best thing to do is call around and find a "Helicoil Kit". This will have the proper size drill bit, helicoils, and the installation tool all in one package. All you need to know is what diameter and thread pitch you want.