409 crack repair

38Chevy

Well Known Member
I worked at a machine shop many years ago and have repaired many cracked block and heads using the case iron tapered plugs. I would start just before the crack and drill and install the first plug. Then I would drill right on the edge of that plug for the next plug continuing on to the end. The finished repair looked almost like a ‘row of dimes’ weld. I would the grind it all down flush and go over it with a small pneumatic punch that worked like a big engraver and the result would look just like the surrounding cast iron
 
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425/409ER

Well Known Member
I welded my other 409 block that had been sitting in the basement for 35 years with muggyweld. The 77 rods worked great. Had nothing to lose by doing this. Both sides held 35psi for 3 hours. I saved it because it was a mint std. bore engine and could not stand to see it go to waste.
 

tenxal

Well Known Member
I welded my other 409 block that had been sitting in the basement for 35 years with muggyweld. The 77 rods worked great. Had nothing to lose by doing this. Both sides held 35psi for 3 hours. I saved it because it was a mint std. bore engine and could not stand to see it go to waste.

A local guy pins the ends and uses the Muggyweld 77 rod with good results.
 
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