Fuel issues on 120 Ford Lehman

bbarnes61 · Sunday at 7:27 PM

I know this has been discussed before but I have not found a definitive answer in any of the threads (could be I’m not looking hard enough).
I replaced my old CAV fuel filters with new spin on adapters. I went to start the engine and it turned over but I had forgot to reopen the main fuel valves. After reopening I went back down and loosened the bleed bolts on the secondaries and pumped with manual lift pump. I also have an electric priming pump by by primary Racors. I tried that but was not pushing any fuel through the line. I unhooked the fuel line from the bottom of the lift pump and turned the primer pump on with no fuel coming out of the fuel line. I’m thinking maybe the priming pump is only for my primary Racors and doesn’t push it through to the lift pump?
I reconnected the fuel line to the lift pump, opened the first bleed bolt in the secondary filters and pumped the manual lift pump. After the initial few pumps it didn’t feel like the lift pump had any pressure. I pumped repeatedly for quite a while with no pressure coming out the bleed hole.
I’m at a loss. Help!

Comodave · Sunday at 7:36 PM

Having an electric priming pump that doesn’t prime the secondary filter makes no sense. The purpose of an electric priming pump is to prime the whole fuel system. Off hand it sounds like there is a restriction or plugged up fuel hose or maybe your new secondary filters are plugged up. Maybe another shutoff valve that you missed? I might try taking the fuel line from the tank to the Racor and see if it is open.

bbarnes61 · Sunday at 7:44 PM

thanks for the reply. I removed the line before the new filters and ran the priming pump with no fuel coming out. I assume the fuel would be running at a pretty good clip with the priming pump on.

RT Firefly · Sunday at 8:13 PM

Greetings,
Is the lift pump arm off the cam?
On I-pad. Terse reply..

SteveK · Sunday at 8:29 PM

The lift pump will not prime if the line has air or is sucking air.
Maybe the electric pump is not self priming also, is it below fuel level? loosen connection to electric pump outlet, fuel should gravity flow if below fuel tank level.

Comodave · Sunday at 9:46 PM

If fuel isn’t coming out with the priming pump and the hose is disconnected at the secondaries then it could be the pickup tube in the fuel tank is plugged. Or is there a shutoff valve at the tank that is closed?

bbarnes61 · Sunday at 10:49 PM

I went back tonight and turned the motor over a bit, re-bled the two new filters, the main line going into the fuel injection and the two bolts on the fuel injector. Presto bango it fired up. Ran it for an extended period with no problems.
I think SteveK hit it on the head there was air in the line and wouldn’t prime.

Thanks for the assistance now on to the stuffing box that’s leaking.

Comodave · Sunday at 11:58 PM

Glad you got it running.

Fuel issues on 120 Ford Lehman

bbarnes61

Member

Comodave

Moderator Emeritus

bbarnes61

Member

RT Firefly

Enigma

SteveK

Guru

Comodave

Moderator Emeritus

bbarnes61

Member

Comodave

Moderator Emeritus

Similar threads

Latest posts