I'm not sure if that has something to do with it or not, but when spark plugs keep backing out- the problem is that the threads are too loose, or you're not tightening the plugs down enough. I'm assuming it's not the second one since you probably increased torque since the plugs loosened.
Get you some nickel anti-seize, the last time I looked here it was $7 for a big grey container of it that you'll get years of use out of. It also comes in little one time use packets for $1, but I see those as a waste. It's much better to have anti-seize laying around- it's very handy. I put some on where my axles fit into the hub so those won't seize up like the factory parts did. There are some places where using it might not be the wisest thing- like pinch bolts. But spark plugs in aluminum heads is a definite must-have.
It's messy. Just use a little on the top threads, and tighten down to 20-25 ft-lbs carefully. If you have been tightening to 20, and that wasn't working, you shouldn't cause any damage by going up to 25- now 45 might be a big deal, so don't go too far on your own.
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Originally Posted by the user formerly known as ZX3_Chick
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