Question: My son bought a dune buggy but the bolts that hold the rockers arms to the engine were broken a long time ago & repaired by screwing these self tapping things into the the head. Well those aren't holding anymore & I was going to try to put bolts through the hole with nuts & washers on the back (could be a problem getting off in the future).
Answer: I think your heads are kaput. If helicoils have been put in the heads, and now those have pulled out, it is time for new heads. I doubt the nut and bolt solution would work. Any failure of the head(s) could ruin the rest of the engine.
New heads aren't very expensive, and I think in your case it would be money well spent.
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