shadowknight

Need some advice. I have been trying to remove a cross threaded spark plug. The method I have been using is spraying the bejesus out of the spark plug with Kroil penetrating oil then turning the plug 40 degrees counter clockwise then 30 degrees clockwise several times then respray. It does not appear that the plug is working it's way out and I'm also concerned at the amount of force required to move the plug in both directions, as I don't want to break the plug. How much force is to much?

WallyP

Contrary to popular belief, it might be easier to remove the plug with the engine hot. The aluminum head (and plug hole) will expand more than the steel plug. (Some people believe that the plug hole gets smaller, instead of larger, as the head gets hotter - nope.)

shadowknight

Wally the engine is in a non operational state. could I use a butane torch to heat it up the spark plug and surrounding area or would that crack the ceramic part of the plug.

dr bob

You won't be able to get enough heat in with a butane torch to make a difference, unfortunately. The engine is a big aluminum heat sink, and the plug is specifically designed with that ceramic insulator so it doesn't pass heat between the threaded steel part and the center conductor. It would work only if the head was off the car, and at that point you'd be better off heating the whole thing slowly in an oven.

Kiln_Red

Is the spark plug actually cross threaded or is it just simply seized?