Originally Posted by SB (Post 4778744)

#7 water to cylinder for sure. Between #5 and #7 cyl could have been letting a little combustion leak between themselves.

Also remember, a misfiring cylinder or two can suck water back like a 20yr old can beer on Thirsty Thursday on campus. :)

Factory heads or aftermarket ? Reason for asking, some aftermarket heads have wider combustion chambers and require a larger bore head gasket, even if larger than cyl bore.

Originally Posted by BillK (Post 4778745)

Just curious ..... was that the Fel Pro marine gasket ? How many hours on it ?

Originally Posted by onesickpantera (Post 4778752)

Hey Scott, long time no talk. Factory 502 (088) heads.

Originally Posted by sonicss42 (Post 4778757)

Be sure to check the exhaust ports thoroughly on those 088 heads. You may need to have them pressure tested. They are known to rot where it is hard to see with naked eye. BTDT. Just another idea in the process of elimination. Good luck.

Originally Posted by Revelocity (Post 4778850)

One other source of water that I encountered - ouch. The Merc belt-driven combo fuel pump/seawater pump can fail and water can be sucked from the failed fuel pump into the intake manifold through the vacuum line.