F 250 strange fuel starving problem - The Hull Truth

cwms · 03-16-2008, 03:39 PM

A1-
I am stuck in the Bahamas. I have a new (40 hours) F 250 Yamaha on a new boat, and it starved and stalled while running. Restarted and went about 30 seconds and now nothing at all.
What I have tried:
- drained Racor filter bottom and it looked fine
- disassembled plastic filter (with wire on it front of engine) and drain it and float flops up and down fine
- drained the phillips screw on the bottom of the big pump (port side) into the hose attached to it- got a bit of flow but not a lot
- tried to pump fuel with the bulb all the way to the liitle hose above but could not get it to flow
- checked the fuses (all, including the ones related to fuel pumps) and all good
The only thing I have noticed is the sound of the fuel pump when the switch is turned to "on" is different. It sounded like a pump before. Now it is a high pitched hum.
I am sensitive about fuel in the bahamas and have only refilled three times from Florida at high volume high end marinas.
What am I missing? The boat is in the water so difficult to work on not to mention get to the nearest dealer.
Thanks for any help.
Carl

A1 Outboard · 03-17-2008, 05:59 AM

You mention that the pump has a humming sound instead of the normal running sound. If it just hums, perhaps the pump is locked up. That happens when water gets into the fuel and rusts the gyrotor pump parts freezing up things.

To find out, you would need a pressure gauge to test the primary and the secondary elelctric fuel pumps to see if they output the correct pressure, both when the key is first turned to ON and while the motor is cranking over.

cgmiller · 05-19-2008, 10:37 AM

CWMS,

I experienced a starving problem on a buddies boat and it turned out to be some debris stuck in the antisyphon valve onthe pickup tube for the fuel tank. The tube is a metal straw with a check ball valve at the end. Maybe you have an obstruction in the fuel line.