TH 350 tail housing bolt hole stripped out !!! Help !

[87BlazeLS]

Hey folks, Just found out I have a stripped bolt on the passenger side of my tail housing on the TH 350.
It is right where the 2 bolts extend through the transmission mount and into the aluminum housing.
The problem Is, there is not much room to drill it out larger or deeper.

Anybody had this issue ? and what was used to resolve it ? Heli coil ? If so what size ?

jake 87BlazeLS

 

[deanlemans81]

I`m not sure what the bolt size is but I would just use a heli-coil of the same size. Get the complete kit for your size bolt and you`ll have all you need. It`s real easy and only takes a couple of minutes.
deanlemans81

 

[ChiefCut83]

I had the same problem happen and after checking it out and talking it over with my instructor, the best thing to use is a EZ-lock thread repair kit it's about 50 bucks with shipping and after a lot of research the size is 3/8-16 course, I purchased mine from used-enco.com ( it has internal and external threads with a red thread lock on it), hope this helps us both

 

[carmangary]

I had that problem on mine, too. Helicoiled it.

 

[87BlazeLS]

It seems much larger like the threads are so bad the bolt would slide all the way home without turning.
Would the helicoil fix that much wear on the old threads ?

Confirm 3/8-16 ? 1985 Th 350 GM not BOP

 

[deanlemans81]

Yes it will. You will basically be drilling a bit bigger and installing an imsert that brings the hole back to it's original size.
Deanlemans81

 

[87BlazeLS]

Does the Heli coil get cut down to fit the depth of the hole ?

Should the bolt threaded area only be as long as the heli coil is deep ????


thanks for all the comments

jake 87BlazeLS

 

[pontiacgp]

the helicoil is designed with the number of threads to safely hold the bolt. You can use the same bolt that you use for that location. Helicoils are used in many parts of aircraft as bolts are not allowed the be threaded into any grade of aluminium or dural without a helicoil