Heli-coil chainsaw?

[scorpio333]

I've got a Stihl chainsaw my dad gave me a few years back. Great saw until I lent it to a neighbor a little back. I got it back yesterday and went to start it up. No start. Went through the troubleshooting steps and found the spark plug was out. Strange. As I'm threading it back in I know something ain't right. The MF'ing head is stripped. It was also set to winter which it wasn't when I last used it. I gave the guy a perfectly good saw and got one back that is pretty much totalled. A new head is $220 and the saw new is $279. I asked him if he had any problems...nope, started right up and ran great. Well, not much I can do to prove he did it or didn't do it. It is quite possible the plug vibrated out, but that wouldn't explain it set to winter.

For now on he ain't getting any tools without a cash deposit for the full cost of the tool. I don't have time for games like this, anything I've ever borrowed from friends they got it back cleaned and ready to use, if something broke I fixed it. I'm keeping my man card and respect other's peoples stuff. I got a stump that needs chopped out and I'm screwed without the saw.

Anyone tried to heli-coil on something tiny like this? It's just a small section of the threads that are stripped, maybe about 3/8th's of an inch.

[Silverhatch]

Don't know about the heli-coil, but that was ****ed up of the neighbor to do that. Talk about not being able to man up.

[John4cam]

You might be able to re-tap the threads back into it enough to hold the plug.

[TooFast98Cobra]

You might be able to re-tap the threads back into it enough to hold the plug.

x2 that metal is so soft use alot of greese

[scorpio333]

x2 that metal is so soft use alot of greese

That's my concern...service guy said they wouldn't even try because they can't guarantee it which I understand. Figure it's worth a shot, can't make it any worse.

[SK@StreetLethal]

I would go with the helicoil. What size are the threads of the spark plug?

[mustang50lx]

They make helicoils just for spark plugs. It will be better than it was new with the insert in it.

[scorpio333]

Stihl calls for a NGK CMR6H which looks to be a 10mm thread size. I've never done a heli coil. My buddy is a BMW tech, but he's sick as a dog right now. Once he gets better he said he'd give it whirl.