One Engine Losing Prime

[kartracer]

While running this weekend port engine shut down and would not restart. During the week we have checked all fuel lines and clamps, check value in fuel line, fuel filter, fuel in tank thought we may have air suction. Found nothing,,,
If you fill the fuel filter manually engine will run until you shut it down. Let engine sit, not running, for 1/2 hour or so and it will not start, filter dry. Can fuel be going back to fuel tank? Filter is lower than tank outlet.
454 Chevy
Electric Fuel Pump

 

[ulysses]

Yes, fuel could be going back into fuel tank. I would check your fuel tank vent to ensure that you are not creating a vacume in tank.

 

[sdowney717]

Also check your tank pickup tube. Mine failed cracked and rotted. Engine would lose prime and randomly quit running.

 

[psneeld]

Also...a lot of fuel lines delaminate and constrict while the engine is running....

If they are more than 5 years old or so...and you have checked everything else...try replacing the fuel lines.

 

[boatpoker]

Dad said "Always check the simplest, easiest, cheapest thing first".
Vent screen .... plugged with spider crap ?

 

[FlyWright]

Had similar symptom once after changing on-engine secondary fuel filter. The filter had failed to seat properly. Disassemble, realign the rubber O ring, bleed the system and problem solved. Hopefully yours is as simple.

 

[FF]

"If they are more than 5 years old or so...and you have checked everything else...try replacing the fuel lines."

If replacing long lines use metal and only use rubber lines as short section to allow for engine vibration or movement.

Learning to flare a metal tube is 5 min of effort.

Buy the tubing bender if a really neat finish is desired.

 

[bayview]

don't gas engines have tank check valves?

 

[sunchaser]

Not an uncommon malady for gassers in this ethanol age. Old rubber lines, "O" rings and gaskets rot out. Unfortunately so do some plastic and FRP fuel tanks creating debris clogs. Carbs or EFI?

Hook up small separate feed jug to eliminate/confirm tanks and lines as issue.