HELP!!!!!
WE ARE HAVING WITH FUEL STARVATION ON AN INTERMITTENT BASIS. BLEEDING THE FUEL LINE IMMEDIATELY RESTORES THE ENGINE TO RUNNING STATUS. HAVE CHCKED AND RECHECKED THE FUEL PICK UP, VENT LINES, FUEL LINES ETC. EACH TIME THIS HAPPENS THE FUEL FILTER IS EMPTY.
ANY AND ALL SUGGESTIONS WILL BE WELCOMED!

My guess is that you have an air leak into the fuel line somewhere after the lift pump (little one on the side of the engine). This would result in air in the fuel line causing the engine to shut down.

Another possibility is that there is some blockage in the fuel line between the main fuel metering pump and the fuel tank. If the pump can't draw the fuel it needs, the fuel pressure on the tank side would drop low enough to cause air to come out of the fuel.

Check the lift pump too. If its not working properly, you'd have the same effect as a blockage.

Good Luck....

[This message has been edited by Alan Grim (edited 07-20-2000).]

I also had a similar problem. I replaced the entire fuel line, but that didn't help. I then bypassed the fuel/water seperator and it worked great. For about $60, I replaced the fuel/water seperator and the engine is running air free.

As the previous post mentions, I believe there was something in the seperator blocking the fuel, which in turn made the engine start sucking air.

I would also check to make sure the screw used to bleed the engine has the brass gasket on it. If not, that could also be an air source.

Good luck

I had the identical problem after I upgraded to a Racor fuel filter on Love & War. The engine would run fine for quite a while, then shut down with the engine filter bowl empty. I'd bleed it and everything would be fine again, for a while. The problem turned out to be the brass plugs Racor provides for the inlets & outlets not used. I had not adequately tightened them, and they would allow a miniscule amount of air in as the fuel pump pulled the fuel through. There was no apparent leaking of fuel out, so visible signs.

Does anyone know the normal operating oil pressure for a Yanmar 15. I find that my engine runs for the first hour at about 38psi; after about an hour it drops down to 21psi and stays there. Is this a problem? I had to motor for three hours this past weekend and it was stressing me out. Help!