ANY HELP WITH THIS FUEL QUESTION WOULD ROCK!!

[Outlaw720]

So my 1980 720 4x4 i dont thing is getting enough fuel. but how do you tell? my set up on it is a 32 36 Weber. but when its running the you can hardly see fuel goin though the filter. it only fills up when the truck is shut off. it idles great. but when i go take it on the test drive it goes from first gear to second great then cuts out. so im not to sure what that means but any info would be very cool! thanks in advance

[DAT510]

how old is the Weber?

My 521 did this and turned out to be the float bowl.

My Z31 also did this, but died after letting off the throttle, but this was because a vacuum leak.

[ggzilla]

Do the fuel pump tests! Click for directions.

[ggzilla]

when its running the you can hardly see fuel goin though the filter. it only fills up when the truck is shut off

That is normal looks. Don't worry about that, instead check that the fuel pump volume test is good.

[Dawa]

lines could be clogged up with rust/dirt, thats what i would check.

[ggzilla]

How do you test that? with the fuel pump volume test.

[datzenmike]

The bottom of the electric fuel pump twists off. Inside is a filter. Check it or replace. Another inline filter may have been added in the engine compartment. A dirty or restrictive filter will cut the fuel flow to the carb.

[Ratwagon1600]

Everything what the other guys have said.

 

I generally start at the fuel tank and move forward to the carb. Looking for fuel flow from the tank, no crimped or bent

Lines, fuel filter(s) clean, fuel pump flowing at correct rate, float level correct etc.

 

Good luck, these things can be particularly annoying.

[Outlaw720]

yeah this whole truck has been a lets find the small issue kinda deal. i love the truck so its worth it to me.

[daddydonuts]

Rubber fuel line not sealing properly? This happened on my Z when I replaced the tank, fuel hose and filters. Check those first before throwing lots if cash at it.