Spark Plug Thread Repair Kit Suggestions?

[woodstover]

When we had our VW aircooled shop we used tons of helicoils for spark plugs/exhaust studs. Always a success. Used red loctite when installing. As a shop, we would buy starter kits for what was required and then just ordered extra inserts kits as required. Slowly built up to having all the common thread sizes. A few seldom used sizes we would buy a longer insert refills and just cut them to length instead of buying different lenghth refill kits.

 

[StarTech]

That is the problem that cheap kit is not a Heli-coil version but is a threaded insert. Plus they are reaming the hole and then tapping it for the insert all in one operation. Next time I try the kit I brought I am going just drill the hole and they tapping it. But I am looking for regular Heli-coil tool sets for the 10, 12, and 14mm plugs. I know three different kits so that is around $400 to start with.

 

[Rivets]

Have you seen this kit, had one in the last shop I worked in, before i retired. For M14 I used spark plug tool. https://www.vevor.com/home-tool-kit...MIpbm_3Y_6kAMV7lR_AB0u8Ra5EAQYCSABEgKZavD_BwE

 

[StarTech]

Not even the right thread pitch.

I need M10-1.00, M12-1.25 and M14-1.25.

 

[sgkent]

thread cert is more common in the air cooled world. The best fix is to make a video on replacing the head, or show someone how to properly remove the head, weld it, surface, and drill / tap a new plug hole. I would only use a heli-coil or thread cert on a head that was NLA used or new, or very expensive. Lots of the old mower engines from the 1990's are out there in masse as to used parts. Both thread certs and heli-coils can fail or be problematic when the plugs comes the next time the it is removed. So ask yourself why go thru all the hoops to remove and then repair it, then put the old one back when you could have a replacement ready to go.

 

[Rivets]

What about these individual kits?

E-Z Lok E-Z Coil Thread Repair Kit for Metal - Standard - M10-1.0 x 3/8 SK50932 | Zoro

Order E-Z Lok E-Z Coil Thread Repair Kit for Metal - Standard - M10-1.0 x 3/8, SK50932 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

www.zoro.com

E-Z Lok E-Z Coil Thread Repair Kit for Metal - Economy - M12-1.25 x .500 EK51034 | Zoro

Order E-Z Lok E-Z Coil Thread Repair Kit for Metal - Economy - M12-1.25 x .500, EK51034 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

www.zoro.com

E-Z Lok E-Z Coil Thread Repair Kit for Metal - Standard - M14-1.25 x 3/8 SK51132 | Zoro

Order E-Z Lok E-Z Coil Thread Repair Kit for Metal - Standard - M14-1.25 x 3/8, SK51132 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

www.zoro.com