I got the truck put back together and an exhaust appointment on Thursday. Went to start the truck last night, and it will run if I pour gas in the carb, but died as soon as that gas burns.

I got it to run last week, no problems. When I turn the key, I can see fuel and air bubbling in the clear fuel filter between the paper filter and carb. However, when I pour gas in the carb and get it to fire, that clear filter showd no movement. Carb isn't blocked I dont believe, I pulled it off and blew through all passages with no issues.

has the mechanical fuel pump died on me?

 

Well let see what we can do.
What work was done that the truck was put back together?
How much fuel is in the tank(s) and please don't say the gauge shows XXX, pour 5 gal in and see what happens.
How old are all the rubber fuel lines? Again don't say they look good. They can on the out side but be bad (plugged) on the inside, just replace them if old. remember the 1 from tank to metal line on frame.
Make sure you use the right size hose when replacing them. I had 3/8" in place of 5/16" on the inlet of the pump and could not pull fuel from a small gas can on the fender.
Pull the line off the carb and place in a container and crank the motor over to see if any fuel come out.
If yes then the carb float needle is stuck closed. Sometimes a light tap with a hammer can unjam them or seat them if needed.

If all that is done and still will not pull fuel take hose and a small container of gas place the gas on the fender and the hose from can to pump inlet and see if it will pull fuel.
If not I would say bad pump. My pump for the 300 six was like $20 - $25 I did not know how old it was and when it had a hard time pulling fuel from the fender can out it came.
I don't have any fuel in the tanks as I don't want it going bad wile I rebuild the truck but got tired of pushing it in & out of the garage.

Good luck
Dave ----

 

Thanks Dave.


the tank has 10 gallons in it, and I replaced all but one of the lines and it was fairly new.


the pump will pump the clear filter half full and then can't do anything else.

I put a bottle over the post pump side and nothing came out, but 12" from the end is the filter. I think pump is tired. Got a new one on the way.

 

Um, did you know that there is a real fuel filter located below the fuel pump in a canister if you have a 352/360/390/302, and one above the pump if you have a 240/300? It is probably so gunked up with crud so that is probably why there is an inline filter on the fuel line. You can take it off with a strap wrench or a pair of channel locks if you are real careful. I would take it off to check it before you change the pump. Maybe you killed the pump because it has so much crap in it. Oh well, a new pump has a new filter on it anyways. Just remember to change it often.

 

Forgot to mention that I changed that filter too. The old one was way over due. New pump will be Here today.