^ i have had the same issue something with the metal they use the heat cycle is too much for it and it weakens your notalone i have had it happen to 2 ls motors but a local machine shop has inserts for the block ( kinda like a heli-coil)
inserts will work. ive never tried them i just try to locate another block. are those heli coils solid or are they like a spring type deal? as long as they hold up to 50ftlbs do it. will save you money
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