How do I install a helicoil?

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Jul 23, 2005
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I've drilled a new hole and threaded it. Now how do I screw the helicoil into it? The helicoil is a coil of wire with one end bent across the diameter of the coil. Does this end go in first? Do I use JB Weld or similar to hold it in place?

The hole's in an aluminum bellhousing, for the starter motor.
 
If you bought a kit it should come with a tool that drives the tang into the threads. If the threads are not too deep you can use needle nose pliers to grab the 90 degree tang (through the coil) and thread it in. Once it is in place (deep enough) you can break off the tang or leave it in. You do not need any thread locker or JB weld because friction holds it in place and the bolt you screw into it will lock it in place.
 
Ok... first you're gonna need to correct drill bit for the OD of the tap... the tap itself, the helicoil, and the helicoil instalation tool.
1. Drill hole as perpendicular to surface as possible, do your best not to ream it out any.
2. Use the tap and tap the thread into the new hole, remember (for anyone who hasn't tapped before, use some sort of lubricant on the tap and don't forget to back track the tap every couple of turns to break off the cut material)
3. Clean out the hole
4. slide the part of the helicoil that cuts across the axis into the tool and start threading the coil into the tapped hole. (Cross axis peice should be first end into the hole)
5. ONce it's threaded in a couple threads deep in the hole, use a punch/needlenose/end of the insertion tool to break off the cross axis peice.
6. The fit of the coil into the thread should be pretty tight, thread a bolt of the correct size into the helicoil and tap it sharply with a hammer, this will help the coil to seat into the thread so it won't move.

I think that should about do it... if I"m not already too late or someone has more to add post it up
 
Thanks for the replies, guys. I'm lucky that all four holes I need to helicoil go all the way through the part. It seems like doing a blind hole would be a little more challenging.
 
krash kendall said:
I was taught years ago to use red loc-tite when installing heli-coils and always have since.
Wow, I sure wouldn't do that! Loctite will not harden in the presence of air. So the Loctite won't harden until you thread your bolt in. And loctite red is too strong. If you ever want to get it apart you have to heat it. When you heat the aluminum part, it will expand more than the steel helicoil, loosening the bond between the two parts. I never use loctite red. I would especially not use it on a helicoil.

Have you ever removed any of the fasteners used on these loctited helicoils? Maybe it works fine, but it's very counter intuitive to me. And I know that the helicoil will work great without loctite.
 
I was taught by my pops who used them in the mfg company he worked for. Used them for steel thread in alluminum parts and they installed them exactly as I put it :shrug: no loctite or anything.
I've heard of those cat inserts, 'spose to be easier to use, but I'm pretty sure they are harder to find
 
I think any Caterpillar dealer should be able to get them, we get them from a supplier called McMaster-Carr. They are and absolute breeze to use and can be drilled out if you need to remove them in the future. Also, since you use a larger than normal tap drill, you really don't have much of a chance to break a tap if it's in a tough spot. But I agree, I sure wouldn't use red loc-tite on thread inserts, I use blue on pretty much anything (but never on thread inserts)and have yet to have anything come loose. I work in a machine shop that services and repairs logging and sawmill equipment so it's very extreme environment. Anything I do on my car or dirt bike seems fragile by comparison!
 
zookeeper said:
we get them from a supplier called McMaster-Carr.

*snip*

I work in a machine shop that services and repairs logging and sawmill equipment so it's very extreme environment. Anything I do on my car or dirt bike seems fragile by comparison!

Thats where we get just about all our small hardware parts at work, which is a small R&D protype shop.

Bikes seem especially fragile. Over tighten a capscrew and suddenly you've stripped a hole for the clutch cover......with no room for even HeliCoils!
 
Hack said:
Loctite will not harden in the presence of air. So the Loctite won't harden until you thread your bolt in. And loctite red is too strong. If you ever want to get it apart you have to heat it.

You only put a little on the OD of the heli-coil. I know it's anaerobic and it will harden between it and the ID of the tapped hole. Just a drop will do, you don't have to dip it in the stuff. And yes red is strong, the heli coil becomes permanent in the original part. Have you ever removed a bolt that somebody had heli-coiled and had the coil come out because it didn't bond with the tapped hole due to being in a warm, oily enviroment? It is very annoying. Just my preference, and I do appreciate that there is more than one way to skin a cat.
 
I agree that too many guys over-use loc-tite. I use just a drop of red when I do use it and I can usually get it off with no heat at all. As far as the frailty of bike stuff, my CRF450 has a lot of aluminum bolts on it and I have to really be careful when tightening the subframe bolts and seat bolts. BTW, Kendall, have you ever spent some time looking through the McMaster-Carr catalog? Jeeez, they have everything!
 
Just because McMaster stocks everything they are by no means the cheepest on everything. I learned this the hard way when I ordered 3 grand worth of stainless pipe fittings that they special shipped direct from their supplier, their supplier turned out to be another company we also order parts from that I had no idea even stocked such an item...as you can imagine we could have gotten them cheaper there.