Low pressure fuel pump going out?

[Joshrloya]

2003 f225 txrb, engine fires up and will run anywhere from 5-45 minutes,then dies. It will not restart right away. By the next morning it will fire back up.
changed all filters except VST... New fuel, new filters.
Any ideas?

[fairdeal]

It will not restart right away. By the next morning it will fire back up.

that doesn't fit with a lift pump problem.
The engine runs off the fuel that is in the VST - that is its "mini gas tank"
the low pressure pump - when it runs - keeps the VST topped up;
but you can substitute for the LP pump with your primer bulb -
if the problem is that the LP pump has let the VST run empty,
you can immediately fill it yourself with the bulb -
in which case the engine should start.

Nothing related to that has to wait for the next morning;
the lift pump is not going to run overnight

Conversely, a flooded condition - too much gasoline in the intake manifold - now that might resolve itself overnight.

[Joshrloya]

Ok,tested the low pressure pump. It works fine.
so I'm still stuck with a dead engine that will fire up when I pump the primer bulb.
Now what to look for?

[TownsendsFJR1300]

A fuel / air leak somewhere in the line between the tank and the engine.

Sounds like your sucking air instead of fuel into the engine.

I'd start with hooking up a portable fuel tank to the engine-to rule in (or out), the main tank fuel lines/ tank/ pick up.

Also if you do a search, there several threads on using clear hose to see/find air bubbles at the engine (bubbles NOT good)..


Something basic, but your screw on, fuel filter (NOT on the engine), make sure the gasket surface is spotless, no corrosion and of course, only one gasket..

[99yam40]

Ok,tested the low pressure pump. It works fine.
so I'm still stuck with a dead engine that will fire up when I pump the primer bulb.
Now what to look for?

Testing the pump does not mean it is running when it should be running.
monitoring the pumps or the pressures to see what they are doing would be the best

[DennisG01]

Just a thought to maybe help narrow things down... immediately after the engine dies, drain the VST into a suitable container. How much fuel comes out? I don't know the exact spec (maybe someone can fill in here), but I "assume" there should be at least enough fuel to equal about half to 2/3 of the VST tank volume?

[Joshrloya]

Ok, so I looked at the Racor fuel/water separator filter housing and found the rear of it was corroded so bad it had a small hole through it.
I had a vacuum leak! Replaced the housing,and problem solved!
Thanks for all the replies👍

[TownsendsFJR1300]

Ok, so I looked at the Racor fuel/water separator filter housing and found the rear of it was corroded so bad it had a small hole through it.
I had a vacuum leak! Replaced the housing,and problem solved!
Thanks for all the replies👍

Great!! Easy fix too!

[DennisG01]

Yes, it's nice to get those easy fixes once in a while. Don't get 'em all that often! Glad you got it sorted out.