Truck starts runs cuts out after a minute of running

[Denace]

I have a 1986 6.2 CUCV. New remote filter, all new lines, new lift pump still have air in the fuel filter. Truck ran fine, I had to pull a head off to get a glow plug out, put it back together it runs for a minute to a minute and a 1/2 then cuts out and will not start again.

 

[cucvrus]

Check your lift pump. There are 2 that fit and one is the wrong one. The lever on the correct one has resistance pumping action immediately upon depression and the lever is short and the spring is inside under the lever. The wrong pump has no resistance and the pumping action resistance takes place about 1" into the lever depression. The cam eccentric can not depress the wrong pumps lever arm enough to get fuel moving fast enough to the pump. The injection pump will pump a minute amount of fuel but not enough to keep the engine running. Been there 2 times. I lived and learned. If you have your old pump look at it. Show a picture here. Good Luck. Check the pump.

 

[sneekyeye]

You want the pump with the straight arm, not the one that has a little bent portion in it. The one with the kink in the pump arm is wrong and won't develop pressure properly.

 

[2INSANE]

Pressurize you’re fuel system to 10 psi threw the fuel tank neck. Check all fuel lines for wetness or leaks.

 

[markg]

if you find that the lift pump is not pumping fuel check the pump rod. i have seen them break after installing a new pump. been there and done that multiple times.

 

[Davetheplumber]

I had to just keep runnning it and running it forever to get ALL the air out.. one time it took hours. It’s nice to put an electric pump near the tank.. then you can open the line just before the IP and bleed it out with the electric pump instead of fire the engine up 100 times. Also, if you fire it up with a bit of throttle to keep the rpms about 1500 is will sometimes stay running while blowing the air right threw the injectors

permanent fix for me was a big block 454 gas engine