helli coil
Race Director
Joined: Jul 2004
Posts: 12,685
Likes: 329
From: Scottsdale Arizona
The only con is that you'll have to drill out the hole a little and thread it for the helicoil. If the hole goes through to the interior of the transmission, the metal shards will too. Also a little challenging drilling and tapping with the transmission in place.
Those aside, no down side. A helicoil is a lot better than a bolt that doesn't hold anything.
Those aside, no down side. A helicoil is a lot better than a bolt that doesn't hold anything.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
If the damaged thread is on the tranny main case oil pan rail, I highly recommend you helicoil that one plus any others that look weak or have worn/damaged threads. I bought a helicoil kit with 16 helicoils, drill, tap, and installation tool. Then I did all the threads that passed completely through the pan rail and some others which had enough depth to assure not drilling into the body of the transmission. The bolts torqued up nice and firm with none of that "aluminum yield" feeling I used to get. And....no leaks so far.
The most difficulty I had was keeping the drill steady during the removal of the original threads. A hand drill will want to grab into the aluminum case and wobble around. If you have [or could rig up] some sort of a drill jig or drill bushing, the job would be easier; otherwise, just hold the drill as firm and still as you can while resting your hands on the underside of the tranny case.
The most difficulty I had was keeping the drill steady during the removal of the original threads. A hand drill will want to grab into the aluminum case and wobble around. If you have [or could rig up] some sort of a drill jig or drill bushing, the job would be easier; otherwise, just hold the drill as firm and still as you can while resting your hands on the underside of the tranny case.
Melting Slicks
Joined: Jan 2007
Posts: 2,589
Likes: 5
From: Salisbury Maryland
Since it's in the transmission, you could try Loctite's Form-a-thread #28654. Good for up to Grade 5 bolts and up to 128 lbs. of torque. Must be clean! But should work for an "in place" repair.
Good Luck either way.
Good Luck either way.
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