Repairing Threads

[moparfreak]

I need to repair two 7/16-18 threads on my ****** case, but I've come across a problem...

I have helicoils for it, but the inserts are not designed for through holes. I need to pass a bolt and stud through the hole, and with the helicoil insert installed, this would be impossible.

Are there any other types of thread inserts that are designed for a bolt to pass straight through?

Thanks,
Adam

 

[Satatic]

So the hole that needs threaded is in the block? You would probably just have to take the trasnmission off.

 

[sberry]

There is a better thread insert tha heli-coil, its called E-zlok thread insert. some auto parts may have them, fastenall usually does. They use common taps and drills too. http://www.ezlok.com/

 

[moparfreak]

The case is on my bench...doing a complete overhaul...

That EZlok thing looks exactly like what I need...thanks!!

Adam

 

[TOMWELDS]

If the threads are damaged on Aluminum, i would put some AL braze (alumalloy) in the hole and rethread it or can you weld a nut on the other side?

 

[swgray]

I have helicoils for it, but the inserts are not designed for through holes. I need to pass a bolt and stud through the hole, and with the helicoil insert installed, this would be impossible.

Are there any other types of thread inserts that are designed for a bolt to pass straight through?

I've never seen a helicoil that couldn't let a bolt or stud pass thru it.

You're supposed to break the tang off.

Wayne

 

[TOMWELDS]

Is there enough meat on there to drill and tap to the next size?

 

[Runum]

Are you sure about the thread pitch? I've heard of 7/16-14 and 7/16-20. I know there are oddball thread sizes out there, just never came across them in an automotive application. Good luck.

 

[89vert]

I'm sales rep for Heli Coil and there's absolutely no problem with repairing a thread that's in a through hole with a Heli Coil thread repair insert.

As far as ez lock being a superior fasteneing system , just ask Boeing Aircraft , Prattt and Whitney , General Motors and the U.S. Military why they choose Heli-coil inserts as an OEM item to provide the maximum in thread strength and longevity in their products .

Just my .02 cents worth....

 

[oldgoat]

I work for Boeing and at small shops and Heli-coil inserts can be ok, but especially if you are using a impact wrench to take bolts out then Heli-coil inserts have a tendency to back out of the tools after a while. We repair the fixtures with Keensert repair. They are basically the same as ezlock except the use a oversize drill for the standard tap and then you have 4 blades that you tap down into the hole tha locks the insert in place. They take more room than Heli-coil but I like them a lot better as long as you have the room to use them.

 

[Charles (in GA)]

As Wayne has already noted, after installation, you break the tang off, then a bolt or stud can thread right on thru. IF the hole is deep and you need more thread, you can stack helicoils on top of each other.

Charles

 

[89vert]

Helicoils are typically stronger than the original threads in most standard materials and castings , especially aluminum . Their installation requires the least amount of metal in the damaged fixture to be removed.

One of the demo's I utilize when I am training distributor sales people , is to have the rep repair a stripped thread in a piece of aluminum. When the repair is complete, I'll have the rep tighten a grade 5 bolt in the hole he just fixed with a HeliCoil until he snaps the head right off .If you tried this in the same size hole tapped into aluminum, you'd strip the thread very quickly!

To ensure that the installation will be as strong as possible, it is imperative that the correct size hole be drilled . Not the closest you have on hand . The exact size specified. Then the correct Helicoil tap must be used . When I receive calls from users complaining about their Helicoils failing , it's typically because they have not followed the installation instructions.