70 horse rebuild problems

[Jugfisher]

I have a 1981 70 horse mercury and I have had it rebuilt 3 times because everytime I get it back with in the first 30 min it burns up the No. 2 piston. Yes the water pump is working fine and yes I had the rebuild done by a certified mercury mechanic. Any thoughts...

 

[hoeser]

Re: 70 horse rebuild problems

I am wodnering what your certified mercury mechanic thinks is the problem, you'd think after 3 attempts he'd have some clues. Now I'm curious!