Thanks for all the help guys. It was indeed a hole in the riser. Spent 2 weeks rebuilding the motor. Finally finished last weekend. Everything started up great, So went to start up the starboard, and the starter is bad. Grrr no problem, run to the marine store and ask for a starter for a mercruiser 3.7 470. He asks me standard or reverse. I say its standard rotation. I get back to boat and install the starter, its cranking fast!!! But it does not fire, I pause for a minute, then try again, BAM metal on metal slam and engine will not turn at all. I get out the remote starter switch to see what is going on. I notice the starter is trying to turn the engine backwards! So I take it back to the parts store, and tell him he gave me a reverse rotation starter. He says no, its standard. Counterclockwise..... I then have to prove to him that he is wrong and its clockwise rotation (when looking from the front). So he then gives me the right one. I intsall it but of course it acts like its seized.
I get someone to come and see what happened he said timing chain broke. I was curious this last weekend So I pull all the plugs, hit the starter and water blasts out of every cylinder..........
So, here is the theory and I would like your guys opinion. I think the reverse rotation starter spun the drive and impeller backwards, thus creating a suction in the exhaust that sucked water up and over the riser into the cylinders. All 4 was completly full of water, but no water anywhere else. oil was clean as no leak down had occured yet. The riser and manifold are 6 months old and in perfect condition. The engine has................ 24 hours..........I litterly just finished break in when the other engine happened coming back in.
HT32BX115 I am definitely avoiding any storms at this point. I have had many of the standard 470 issues, and many more of the WHY ME issues that just should not have happened unless your luck has run dry, and my luck ran dry the minute I bought this boat. Seriously, every time something goes wrong, its worst case. I started doing all my own work thinking that it was just poor mechanics in the area, but no. Its a combination of very bad luck, and some very efficient boat gremlins that just dont give up.