Extension to Case Heli-coils?

[Grasor]

Hi all,

I was reinstalling my extension housing tonight and ran into a snag. I think when this transmission was remanufactured the installer put in heli-coils in each of the extension to case mounting bolt holes and one of them busted felt like the bolt had stripped out and just kept turning. As always - it was the last bolt too.

see pics.

I'm pretty sure at this point I'll need to drop the pan to make sure any metal particles that fell out are removed - which is a bummer - but at least I can take the opportunity to adjust the bands.

On the issue of the "heli-coil"

1) is that what I'm looking at?
2) ...what now? Never worked with these.


1979 Scout 2 w 727 Dana 20

 

[FDChappie]

That looks like the threads have stripped out of the aluminum case. You will need to heli-coil that hole now. It's pretty easy to do just make sure you break off the little tab after it's installed so it doesn't find it's way to something critical in your xmission.

 

[Grasor]

I figured as much. Two follow-ups:

1) is the heli-coil tap the same as a standard tap I would have in my tap and die kit? Or is this a heli-coil specific tool?

2) think I can just run a heli-coil back into the hole if the original heli-coil threads are ok? I cleaned it out and ran a bolt in, I could feel that it was grabbing but then it hit the las 1/8" of remaining heli-coil and stopped. Possibly I could just get away with the inserts?

 

[Scooter]

The tap for heli-coils are specific to each size of coil. Almost any hardware store and some auto parts stores carry kits that come with the tap, helicoils, and insert tool.

If the threads have been repaired in the past by some random po, and remnants of old helicoil are still in the previously repaired hole, then the old helicoil needs.to come out before a new one can be inserted

 

[Grasor]

Thanks scooter. You're always a big help.

 

[Scooter]

You're welcome. Glad I can help when I can. Mr chappie is always good on the help factor too. Seen some of his helpful tips often. I actually went back through my last post to fix some typos. Phat fingers on my toy phone gets all cross eyed sometimes.

When it comes to helicoils, I really don't like using them. But sometimes they can be a necessary evil.