Re: 359 Spark Plug Threads Stripped

Posted by Tim Cole On 2015/6/12 17:28:59

GM specifically advises against using anti-seize because the plugs run deeper into the head before achieving torque. After long usage the carbon build up on the exposed threads will lock and tear the threads out of the cylinder head upon removal.

So I would use anti-seize only when specified by the manufacturer.

Most of the Packard 12s with aluminum heads have been converted to larger plugs that won't break off in the head.