No fuel to fuel pump

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Jason Lester

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My truck sat in a garage for years. When I got it home I decided to unhook the fuel line to the pump and use an electric
Pump to empty the tank.
At about 2.5 gallons it acted like it was empty. No more fuel flowed from the tank
So I assumed it was empty. I filled it with 5 gallons of gas and put an inline filter in place. Cranked on the key and no fuel was pulled through the filter. I hooked up a boat tank and it pumped from it on the mechanical pump. At least some and ran ok. I tried the electric pump again and nothing from the tank.

Now my question is what is the likely cause of nothing coming through the tank/lines up to the pump. Some kind of blockage?
Can I blow Air back through it to clear anything in the lines without causing damage?

thoughts? Trying to avoid dropping the tank for now.
 

Blue Ox

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There's a plastic screen on the end of the pickup tube in the tank that is probably plugged with gack. If you blow back through the lines with shop air you'll probably blow it off, which is not desirable. If you have a regulator you could probably push a few psi to try to clear it, but whatever crud is in the tank will probably just get sucked back into it. Most likely you're going to end up pulling the sender to clean the tank.
 

Jason Lester

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That is kinda what I was thinking. I was hoping the sock wasn’t the cause. The fuel looked normal not dark when it came out. So I was hoping it was ok.
I guess I’ll plan on dropping the tank again.
I was originally thinking I’d replace the tank and sending unit.
 

Blue Ox

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Maybe you can pull the filler hose off and dip your pump pickup in there to empty the tank and see what you've got in there. Also, where are you attaching your pump? Is it right at the tank, or are you closer to the front of the truck? It's always a possibility that there's a bad hose in the system. Although I'm never that lucky.
 

AuroraGirl

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Have you tried putting fuel in the tank and connecting the fuel sender to the fuel pump

Took forever but that was my problem once (hopefully someone sensed my sarcasm)
 

Octane

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Reverse blow the line and it may not ever build up again to stop it up. May just send all the stuff thru in small enuff particles to be caught by the filter.What I'd do anyway first.I know this is hard to admit,but I owned a Gremlin...it had blockage at the sock filter.Dont tell anyone I owned a Gremlin.Lol
 

bucket

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I agree, I'd reverse blow the line with air. If it blows the sock off then it was probably plugged up and garbage anyway. Just be sure to run a good sized filter inline before the pump.
 

Blue Ox

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If it blows the sock off then it was probably plugged up and garbage anyway. Just be sure to run a good sized filter inline before the pump.

And never let the tank go below 1/4 full. That sock serves as more than a filter.
 

Corvette Ed

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If you blow it out just go easy with the pressure.
 

bucket

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And never let the tank go below 1/4 full. That sock serves as more than a filter.

Eh, maybe to some degree. I've never found that the sock really keeps the pickup wet when the fuel is sloshing around.
 

Blue Ox

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Eh, maybe to some degree. I've never found that the sock really keeps the pickup wet when the fuel is sloshing around.

Vehicle stalls after turn. I've known many occasions where that has been a significant problem. Including a 1970s vintage Army Jeep. Do what you like, but don't plan on the throttle after a turn with a low tank.
 

AuroraGirl

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Reverse blow the line and it may not ever build up again to stop it up. May just send all the stuff thru in small enuff particles to be caught by the filter.What I'd do anyway first.I know this is hard to admit,but I owned a Gremlin...it had blockage at the sock filter.Dont tell anyone I owned a Gremlin.Lol
we will keep your secret
 

bucket

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Vehicle stalls after turn. I've known many occasions where that has been a significant problem. Including a 1970s vintage Army Jeep. Do what you like, but don't plan on the throttle after a turn with a low tank.

A lot depends on tank design too. Tanks that are more upright in design, it won't matter one bit. But a long saddle tank like these trucks, yeah I agree the sock is definitely going to help some. But if it's just trying to clear a line and see if the truck will run, I'll blow that sucker out with zero concern for the sock. If the tank ends up having to come out, the sock should be getting replaced anyway.
 

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