Stihl 460 spark plug hole

Dougfur · May 13, 2022

I recently bought a 460 off Craigslist. Went to put a new plug in it and noticed the plug was way smaller than the hole. Then i notice what seemed to be a reducer on the old plug that came out of the head. Is this a normal part that stays in the head usually, or did somebody strip it, drill it out and thread this reducer in?

Maintenance supervisor · May 13, 2022

Its been stripped out. Thats a threaded insert.

Dougfur · May 13, 2022

Ok thanks. Should i put something on it to lock it in the cylinder? It comes out with the plug now

Maintenance supervisor · May 13, 2022

It needs to be air tight or you run the possibility of the saw running lean and ruining the piston and cylinder.
In my opinion its best to remove the cylinder and have a reputable welder fill the plug hole and re tap it.

stihltech · May 15, 2022

The repair insert came out with the plug. If you can remove it from the plug, you may be able to reinstall it. I would recommend a new.insert.so that it can be swdged at the top. Red rtv is what is recommended by the insert manufacturer. Common issue that can be repaired as long as the threads in the cylinder are still good.