Helicoil

[Hookmaster]

Last night I started my 20-year old Craftsman lawn mower (20 or 22 inch self-propelled) on the first pull after sitting over the winter. While I was cutting some deep grass (courtesy of the dog) it was laboring and spit the plug. How much does it cost to put in a helicoil if I do it myself? What tools are needed to do this? I may just buy another small push mower since all I use this for is trimming certain areas my rider can’t get into. I have definitely gotten my moneys worth from this one.

[Jigging Joe]

I would say the kit would cost around $15, it usually comes with the drill, tap, helicoil, and insertion tool. Napa should have it or any other parts store.

[Surface Tension]

As Joe mentioned they are sold in a kit with everything you need.

Since removing the head is easy you might want to look for a new or used head and new gasket instead though.

[cygnus]

A complete kit with tap, drill and helicoil could be over $30. I think the ones we sell are even more then that. Regardless, a new cylinder head for that machine might only be $25-35. If that's the case, don't even screw around with the helicoil, get a new head.

[Eric Wettschreck]

If it were me I'd be looking for a different head. I'm not a fan of Helicoils. Eventually most of them fail. Not all, but a lot.

[NEXPLANAR]

Wouldn't it be easier just to go out and buy a new lawn mower? Being that its 20 years old already.

[harvey lee]

When we were racing go karts, we use to use those alot of exhaust bolts and carb bolts and had very good luck with them.

Personally I would look for a used or new head.

[Shack]

I used a a Heli-coil repair on my sons dirtbike about 3 years ago. It might be cheaper because your thread could be standard and it is sold as a complete kit for one shot. My sons Honda was a metric small sized thread. I had to buy a complete shop type kit which ran about $60-$70 dollars.

He is pulling and seating the plug all the time and has had no issues. In my case it was either $150-$200 for a used head and about a day or so of installing it in my spare time, or $70 and about 10 minutes. It was an easy choice.

If it came to a blown spark plug in your daily driver vehicle I would pass on any Heli-Coil, but instead use an insert style thread replacement.

I guess as far as what your final outcome should be, only you my friend can answer that. If we are talking a push mower, the newness of a new push mower lasts about 2 mows. Then at that point you are thinking the $50 (+/-) to fix the old one might not have been all that bad.

Good luck!