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Old 01-30-2009, 10:39 PM   #1
drewfever1020
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Location: san antonio, texas
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gas question?

ok iv noticed that my gas in my gas filter goes down when i turn my truckoff
why is that?
i have to pump to get the gas to my carb cuz my gas goes idk were haha
anyone?
can it be my fuel pump?
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Old 01-30-2009, 10:52 PM   #2
Kayotic
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Re: gas question?

Is the tank vented?

Is it vented properly?

Also check the cap..
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Old 01-30-2009, 11:08 PM   #3
drewfever1020
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Re: gas question?

u mean close proply?
there cant be no air excaping?
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Old 01-30-2009, 11:16 PM   #4
mr48chev
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Re: gas question?

It is pretty normal on these trucks and yes the fuel pump may be a bit weak letting the fuel flow back towards the tank.

You have to have a vented cap or the fuel pump will create a vacuum in the tank when the engine is running but that is not your problem. If you don't have a vented cap the truck will act like it runs out of gas in a couple of miles when you get a vacuum in the tank. An easy way to check that is to carefully open the tank if the truck does die and listen for air rushing in and the sides of the tank popping back out.

What usually happens to cause what you are talking about is that the valves in the fuel pump get a bit worn or dirty and let the fuel bleed back towards the tank and don't maintain pressure against the needle valve.
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Old 01-31-2009, 12:37 AM   #5
Longhorn Man
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Re: gas question?

however, you will pretty much always need to pump the throttle to fire a carb'd engine.
Basicly, don't worry about it.
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