Fix-a-thread. how?

[Izeloz]

Hey, I just stripped out the bolt holes on my aluminum bellhousing. I bought a fix-a-thread kit from Auto-Zone to fix it and I want to verify some things. It says that the bolt size should match the tap perfectly. That's what I don't understand. Do they mean the tap should match the heli-coil perfectly? I don't see how you could drill out the hole and tap it with the supplied tap and THEN insert the heli-coil and have the bolt match the tap. Anyone who could shed some light on this for me would be greatly appreciated. Basically my question is, should the bolt match the tap supplied in the kit exactly or should the tap be larger than the bolt?

[hy_desert_4wheeler]

The bolt should fit the helicoil.. The tap should be the same size as the outside diameter of the helicoil..

[Balsax]

The bolt should fit the helicoil.. The tap should be the same size as the outside diameter of the helicoil..

What he said...

Helicoil taps are special because they have the thread pitch of the bolt but are a larger diameter to make room for the helicoil insert. I've used them many times and haven't had one fail yet. They work great for aluminum things. Make sure that you have the correct size drill bit and just go slow with tap. Screw the insert onto the tool and thread the insert in with their tool until it's flush and then break off the little "nub" on the bottom of the instert with a screwdrier or something.

Good luck

[Grapehead]

how many holes did you strip out?

helicoils arent what you want if it is a lot of them.

[ironpig70]

how many holes did you strip out?

helicoils arent what you want if it is a lot of them.



exactly. do it like a math problem if its more than say 25%( i have 7 bolts in my so if i stripped 2 then it would be 2/7 =28%) i'd figure out what size tap i'd need and retap the holes to the next bolt size if possible. so if there 7/16 you may want to tap them to 1/2"

[stupidfast]

its not too hard to figure out. if you bought a "kit" then all of the things u need should be there. first you drill out the stripped threads with a drill bit that will match the diameter of the inside of the treads of the helicoil (i forgot all the proper terms for diameters). then you tap the new hole, and use the tool to screw it in. then, like somone else said, break off the little nub. the helicoil should have the same pitch and diameter of the bolts your using in your bell housing. when all is done, good as new. and dont use cheap fixes for motor/tranny parts like the matchstick or toothpick trick. the only time u can use that is on something insignificant, like the screw that holds a plastic pannle of interior on or something.

['71 800B]

Time-sert is the way to go.

[packnrat]

if you bought a kit then the correct drill should be in there,

the correct tap should be in the kit also.

and the inserts with the correct tool to put them in the hole.

this = kit.

[Peter_C]

Time-sert is the way to go.
Agreed Time-Serts are best system. Heli-Coils are junk and fail. Nothing under stress should ever use a Heli-coil. Plus when removing a bolt it will often pull the Heli-Coil out with it.

[mudslinger99]

Time Serts are the way to go..

What are the specific advantages of TIME-SERT over Helicoil?
The TIME-SERT inserts have a flange, which will give them a positive placement on installation, for “accurate specific depths”. This ensures that the insert does not wind down into the threaded hole. TIME-SERTs are solid bushing and self locking, TIME-SERT being a solid bushing insert gives it added strength. TIME-SERTs have no messy prongs to break off down in the hole which can be a problem in deep holes. TIME-SERTs are self-locking having an actual locking feature which will prevent them coming out when a bolt is removed, again adding to the advantages over coil types. TIME-SERTs are timed internal to external, which give them a thin wall for tight applications but added strength over the coil styles, and can also use loc-tite, if so desired.