1982 250cu fuel issue

[Chazmaz]

Truck was running fine for past few months. After painting it a few weeks ago, I went for a ride and only made it 1/2 mile. It was stumbling and ran out of fuel. Truck has new carb and fuel pump and fuel filter, so I changed out tank and pickup assembly, also replaced all rubber lines. Will not start now. I primed the fuel lines and it will run long enough to burn that off but then stops. Any ideas?

 

[Rickf]

What came first, the new carb, fuel pump and filter or the stumbling? Have you tried to crank it over with the fuel line disconnected from the carb to check flow? Have you tried to put air pressure (5psi max.) to test between the tank and fuel pump inlet hose to check for restriction?

 

[YakkoWarner]

Truck was running fine for past few months. After painting it a few weeks ago, I went for a ride and only made it 1/2 mile. It was stumbling and ran out of fuel. Truck has new carb and fuel pump and fuel filter, so I changed out tank and pickup assembly, also replaced all rubber lines. Will not start now. I primed the fuel lines and it will run long enough to burn that off but then stops. Any ideas?

I had a brand new mechanical fuel pump on a Jeep (using the GM 4 cylinder "iron duke" engine) that failed after the first startup - probably the same pump your GM 6 cylinder uses. I'd pull the line off the inlet side, run a temp. hose to a gas can or boat fuel tank and see if it pulls fuel from there. If the answer is "yes" then you know the problem is futher back in the lines or tank.

 

[Chazmaz]

Carb and fuel pump been on 4 months. In-carb filter was very clogged a few weeks ago so that's why I changed tank. I put another fuel pump on just to make sure I didn't have a defect. I blew air thru the lines to check for restrictions.

 

[Ricko1966]

Pull the fuel line at the carb,route it into a bottle or can. Prime the carb and start tge engine. Did you get a can full of gas? Yes? Pull the top off the carb check for trash in the needle and seat and the float bowl.no? Pull the inlet line off the pump route a line from a lawn mower can of gas to the pump. Prime the carb start it. Did you get a can full of gas? Yes? hook the carb line up see if it runs on the lawn mower can. No? see if the pump eccentric is moving the pump arm. Yes?replace the pump. No? Let us know things just got deep.

 

[Chazmaz]

Awesome, sounds like I got work to do. Thanks for the plan!

 

[Chazmaz]

Pull the fuel line at the carb,route it into a bottle or can. Prime the carb and start tge engine. Did you get a can full of gas? Yes? Pull the top off the carb check for trash in the needle and seat and the float bowl.no? Pull the inlet line off the pump route a line from a lawn mower can of gas to the pump. Prime the carb start it. Did you get a can full of gas? Yes? hook the carb line up see if it runs on the lawn mower can. No? see if the pump eccentric is moving the pump arm. Yes?replace the pump. No? Let us know things just got deep.

Hey Ricko,
I pulled the feed line off the fuel pump and put it in a glass jar of gas. Truck fired right up! So, I must have a plugged hard line to the tank, probably rust from the old tank. I'm gonna use new rubber gas line from tank to fuel pump. Thanks again!

 

[Ricko1966]

Hey Ricko,
I pulled the feed line off the fuel pump and put it in a glass jar of gas. Truck fired right up! So, I must have a plugged hard line to the tank, probably rust from the old tank. I'm gonna use new rubber gas line from tank to fuel pump. Thanks again!

Run a steel line with short rubber couplers 1st try to blow the line out.,make sure that there are no holes in the existing steel or rubber lines.