Engine cuts out in rough seas - fuel tank problem

[Kathleen]

We have just purchased a 1991 Catalina 28. The previous owner mentioned a problem with the fuel tank and "sending unit" in the tank. The movement of the fuel into one of the baffled chambers in the tank causes the "sending unit" in the tank to be out of contact with the fuel, and thus the engine cuts out. She turns off the key, waits a few minutes for the fuel to settle down, and restarts the engine. This sounds a bit strange, however we wanted to know if anyone else has experienced this or a similar problem, and how to correct it? Thanks!

 

[Matt Blender]

Engine cuts out

I always understood the term "sending uunit" to refer to the mechanism that simply tells you how much fuel there is in the tank. That has nothing to do with getting the fuel from the tank to the engine. Your problem sounds like crud in the bottom of the tank that gets stirred up in rough seas and clogs the fuel line. I would also look at the inline fuel filter, if you have one, and make sure the element is clean.

 

[Joe Barrett]

Fuel Filters

Kathleen, I was coming back from Key West in my new(one year old) Catalina 320 in very rough seas and was surprised when the RPM dropped and the engine died. I replaced both fuel filters (now I know how!) and had a Ft Myers company called Florida Sludge Suckers come and polish the fuel & tank. No problems since then. I agree with Matt the sending unit sends a message to the fuel gauge telling you how much fuel is in your tank.

 

[Garry]

bAFFLEMENT

The baffles in your fuel tank are solid across the top to prevent sloshing but should have openings at the bottom to allow fuel to drain back into the pickup area. It is hard to see how this could have the effect you describe. But the problem might lie elsewhere, namely in the engine oil level. If the oil level is low and the seas are rough the oil pump might run dry and oil pressure drop. Many engines have automatic shutoffs which operate when the oil pressure drops. If the return galleries in your engine are gummed up the lubricating system may pump so much oil up into the cylinder head that the sump runs low. Continuous heeling may contribute. Check the oil level and flush the oil galleries.

 

[Larry W.]

Engine cutout

Kathleen; The sending unit is a float mechanism that shows how much fuel is in the tank. Could be the fuel level is low and rough seas caused the pick-up tube to suck air briefly. Also, check the bottom of the pick-up tube. If it has a screen on it, cut the screen off and throw it away, let the filters do the filtering. Take a diesel engine class, it'll give you insights into what is happening inside that pile of iron.