Pilot II generator hydrolock

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rgano

Guru
Joined
Oct 8, 2007
Messages
4,995
Location
USA
Vessel Name
FROLIC
Vessel Make
Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
Because my lift was damaged during hurricane Michael, I have been forced to moor my boat in the water next to the lift. The engine exhaust ports are on the starboard side which is exposed to occasional rough weather (one mile of fetch to the south) as winter fronts pass by. I have been running the boat including the 3.5 KW Nextgen generator (brand new last June) every week to ensure no barnacles grow on the naked propeller and trim tabs. A few weeks back I found the generator would not turn over and removed the glow plug finding the suspected water exited when the unit was cranked. I have no doubt that the low rise exhaust filled as wave slapped the side of the boat during a frontal passage. And no, due to debris underwater from the destruction of my boat lift cover, I cannot safely reverse the direction of the boat. Luckily, the generator seems to be working well in the ensuing weeks indicating that I caught the problem early. Until my lift is repaired, I am keeping an ordinary sink drain plug in the exhaust and the seacock shut when the unit is not operating. There is a brightly colored cord from the plug to a red object lying in the middle of the cockpit deck to remind me of the shut condition of the cooling water circuit.
 
You dodged a bullet.


You could have bent a piston due to the hydrolock or corroded some valves due to the sea water inside. I assume you have changed the oil a few times.

That genset originally had a poorly designed exhaust riser. If you had the old one that could have caused the problem, although I suspect it could still happen with the newly designed riser in the conditions you described. Slugs of water go over the exhaust hose high point, fill the lift muffler until the water is high enough to back into the engine.

Plugging the exhaust is a good solution.

David
 
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You could just hang something on the generator ignition switch, similar to how you lock-out an electrical circuit on a panel when you're working on that circuit. I'd hate to be constantly walking over something sitting on the floor with a line running off somewhere.

I might be a little OCD though.
 

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