My 55SS with 8v92's has cracked both heads on the starboard engine in the last 2 years. Today, I take the boat from my dock to the travel lift for winter haulout and find the port engine coolant bottle full and foaming. The engine was warmed up and never more than idle. I'll have to figure which head but thinking of just replacing both over the winter because I have more time and can pull the floor to make it a bit easier. Is there anything I should check while I'm doing this that might help explain it? The only common thread is that the previous owner replaced the heads. The mechanics around here say he wasn't the mechanic he thought he was so maybe he used poor heads or faulty installation? I don't see how, I've owned the boat for 3 years so I think faults would have shown up before. The only other information i have is that the previous owner did an engine flush prior to me buying it and i did fint lots of crap in the overflow bottles that I had to clean out repeatedly for a year.