Trying to put in new plugs. 1989 Chevy truck 350 engine. Cast iron heads. Two of the plugs are stuck tight. When I put pressure on the wrench it just does move. It feels like the threads are fixing to gauld. Now, before I wring these threads out, how is the best way to remove these plugs? Also, What should I put on the threads so that I don't have this problem next time?
Thanks
Ugh... Yes... Avoid all inkling to turn them out without getting some lube on them. Short of pulling the heads, and if you can lay it up for a while, Run the engine, Rev it up good and high, then dump ATF down the intake till she's smoking and choking off.. then, Kill the engine with the key while still pouring it in. Hopefully, you will get a "wet batch" splattered all over inside. The ATF will penetrate the threads.
Then, use some penetrating oil down in the plug recesses and let it sit for a few days.
The ATF will not do any damage if not overdone, and the wait will sure beat the amount of work you will have to do if you tear out the threads. Helicoils are certainly not as nice as original threads !
Grummy
Hot Kroil soak for as long as you can wait, a couple of days? A good couple of raps on the steel part not the insulator. Copper filled "Anti-seize" I like it better than the Aluminum flavor.
PB Blaster worked for me on my Dodge pickup.
i
Ruin to get warm. Grab a bithday cake candle and stick it down beside the plug to melt it in around the base of the plug. Warm it up a few times, and work the plug back and forth just a wee bit at a time when it is warm.
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