Engine issues when driving with 1/2 tank of gas or less.

[handloader90]

'76 K10 SWB
355 SBC, mild cam, Edelbrock 1406
700r4/208
D44/12 Bolt 3.08 gears
33x12.5x15 A/T's

My truck is having issues when the fuel tank is 1/2 full or less (forcing me to fuel it up every other day).

When I sit at a stop light or stop sign for anything over 1 minute or so the truck engine starts to run a little rougher, enough where it shakes the truck a little. The rpms drop just a tad, I can hear it from the engine/exhaust and see it on the tach, it might drop from 500 rpm to 400 rpm, nothing too horrible.

Now when it comes time for me to go through the light/sign and I give it a little gas it hesitates... real bad and I have to limp through until I get on a straight stretch and its a constant battle with the gas pedal of letting off and giving it gas and after some time it will go back to regular.

It's really pissing me off and I want to blame it on the Edelbrock carb but it never used to do this.

It is extremely hot where I am now and the humidity is ridiculous. Could it be that my fuel is too hot or theres a lot of fumes in my tank, pick-up problems?

The carb is tuned good, the timing is pretty good, spark plugs and wires about 3 weeks ago.

 

[handloader90]

Also, the engine temp stays fine through all of this. I have a massive radiator and mechanical fan and the temp is always consistent even when stopped for long periods of time.

I do not have an oil pressure gauge so I can't monitor that.

 

[riflerk20]

I would guess the rubber line between the sock and hard line in the sending unit is bad

 

[diesel4me]

My first guess too...keeping it submerged by topping off the tank makes it run better because no air gets sucked in,instead of gas...

 

[mckustomfab]

X3, The big problem is the pressure to the engine is low because its all pushing back into the tank. I spent about an hour dropping my fuel tank to replace a 4" long piece of submersible fuel hose! But at least it will only really cost you time!