Loss of fuel flow to tank

[dshultis]

Great Boat is a 1985 3100 Open.  Fuel path is Tank/Water Separator/Fuel flow sensor/Fuel filter/Fuel Pump then Carburetor.
Engineer runs great til fuel filter empty’s then shuts down.  Fuel filter is not getting fuel from tank.  Water Separator stays full but fuel filter not replenishing. Brand new fuel pump, water separatorand fuel filter in the spring. Ran terrific all summer. Please anyone, any thoughts would be greatly appreciated!!
Dean

[Uhehner]

Great Boat is a 1985 3100 Open.  Fuel path is Tank/Water Separator/Fuel flow sensor/Fuel filter/Fuel Pump then Carburetor.
Engineer runs great til fuel filter empty’s then shuts down.  Fuel filter is not getting fuel from tank.  Water Separator stays full but fuel filter not replenishing. Brand new fuel pump, water separatorand fuel filter in the spring.  Ran terrific all summer. Please anyone, any thoughts would be greatly appreciated!!
Dean

You did not say if there is an ANTI-SIPHON  valve in the line at the tanks 90 degree fitting.  They are known to stick and sometimes just a tap opens them up.  A clear piece of tubing in the line is a way to check for bubbles and an air leak. And then there is always the plugged tank vent problem.  Do you have the problem if you open the gas cap ?

Capt. George

[jclark003]

If water seperator remains full and filter drains I would suspect an air leak between the two, possibly the flow sensor or seal in the water sep. Otherwise capt George pretty much captured other likely suspects. ive seen old / cracked fuel lines let air in and also have had pickup tubes crack and allow air to bleed in when tank level drops.

[dshultis]

A. S

If water seperator remains full and filter drains I would suspect an air leak between the two, possibly the flow sensor or seal in the water sep. Otherwise capt George pretty much captured other likely suspects. ive seen old / cracked fuel lines let air in and also have had pickup tubes crack and allow air to bleed in when tank level drops.

Using cross connect, I ran Port engine off STBD tank to make sure STBD tank ok. Ran great 15 min. Back to normal lineup and replaced STBD water separator. Runs great for 15 min. Today still great.  Not sure what really fixed it other than I put in new separator??
Dean