Stripped Bolt

[Av8r3400]

A T-40 torx bit is .260" from point to point.

A 1/4" (.250" flat to flat, .289" from point to point)

A 6mm (.236" flat to flat, .272" from point to point).

This makes a t-40 an excellent tool to tap into a stripped 6mm socket head cap screw. The torx bit will hold much more torque than a hex shaped socket.

Give it a try and see.

Some heat is good to release locktite, but heating the aluminum is dangerous. It may damage the case if too much heat is applied. Never use a torch on this application. Heating the screw itself will only make it expand and get tighter.

Heat the whole area with a heat gun.

[Slyfox]

sorry i disagree totally on this. I been doing transmissions for 30 years and have been using my techniques for as many. You must be going on theory on what you say. If you are careful and use a very small tip you can heat up the head of the bolt and it will come out. I can prove it through having to do it. Sorry guy.

Now this is my theory, you heat up the head with a torch, you concentrate the heat right at the head. Sure the bolt will expand, but, what I think is important here is the head releases itself from being a clamping force on the parts. So now you have just the bolt to turn out. I don't remember the bolts having locktite on them when I did my gearcase on the 912ul, but that might have changed. With my procedure that to will be taken care of because it doesn't take much heat to release the locktite. So tell me, did the bolts you did take out have locktite? It should be a white look and caked up on the threads, not only that the bolt will come out tight all the way out.

If you are skepticle just put small amounts of heat at a time to the bolt and try unscrewing it, if it doesn't work, add a little more heat. Years ago I thought like you and fought with removing bolts that stripped the heads, than I grabbed the torch and started getting them out.

steve

[Av8r3400]

Do as you like. Personally I wouldn't get anywhere near my $20k motor's gear case with a torch, but that's just me.

In 30 years of tranny work, I'm very surprised you haven't used the torx bit trick. That's not theory; it works very well. (Almost 20 years of being a machinist.)

[horsepower]

Believe it or not it works,I cant say that I have tried it on a aircraft part but do it all the time on outboard motors.If you heat just the head of the bolt the aluminum will pull the heat away from the bolt real fast while actually shrinking the bolt and expanding the threaded hole that the bolt is in.The key is to have all the tools ready and timing is everything, dont dilly dally and most likely it will come out.There are other ways to do it but this is the method I use.Good Luck Randy

[SkyPirate]

I've use heat also on bolts to remove them,..on race cars ,. airplanes ..bull dozers,.. excavators ,,it only cost 500K for a john deere 992 excavator,..don't worry about the cost ..just use the method that does the job right because what ever it is your fixxing isn't worth anything if it isn't working properly

Chase

[Paul Z]

Don't heat it up like you are trying to weld it, and keep the Center of the flame on the Allen Head. All you are trying to do is heat up the bolt not melt the aluminum!

[Slyfox]

I use torx bits, allen bits and those grippers that go around the outside of the bolt. Whatever grips. But you have to heat up the bolt or you will loose the war.