Merc V-6 EFI jet problem

[nokaoi]

Today i was out on the water cruising at 30-35mph when my jet boat suddenly lost power and the engine started sounding rough so I waived down a tow and brought the boat home when cleaning it i tried starting it and it turns over but won't crank and when i looked at the exhaust there was oil leaking out of it? any idea what might be wrong?:(

[pondmedic]

Sounds like a blown head gasket. Worst case scenario...cracked head or block. You have water in your crankcase and cylinder head. If it won't turn over, you've bent a rod.


I know this because I just did the same thing (without bending a rod) to my 460 in my 76 Hondo.

Get ready to shell out some bucks for a good engine machinist to rebuild it. Mine is getting a complete machine job and rebuilt with all new internals for $2500.

Good luck!

Trent

[rockdamage]

compression check 1. should be 120-135lbs

check fuel for water 2.

check for spark 3.

most likely the oil was just unburnt juel that was discarded from your engine during start up.