Gas out of top of Rochester Carb

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Eighty5ov

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I’ve about had it with this Rochester Quadrajet.

Recently just had fuel starvation to the thing, the check valve in the fuel filter wasn’t operating. Changed that. Before that problem the truck ran good.

Now after start up, it runs good for 20 seconds and then fuel comes out the top from two openings. I don’t know the technical terms but the skinny tube at the top front and the skinny slot in the middle top.

Any suggestions ?
 

Octane

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Float stuck.Rebuild,replace needle,seat and float.The float doesnt usually come in a rebuild kit.They are some kind of fibrous weird material.After years sitting in gas the swell just enough to occasionally stick.I rebuilt my carb.And found this to be the case.Had to open it back up and replace the float
 

Ricko1966

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Float stuck.Rebuild,replace needle,seat and float.The float doesnt usually come in a rebuild kit.They are some kind of fibrous weird material.After years sitting in gas the swell just enough to occasionally stick.I rebuilt my carb.And found this to be the case.Had to open it back up and replace the float
To add to this get a non windowed needle and seat. Are you running the factory hardline or is there a section of rubber hose anywhere between the pump and carbureator. If so pinch the rubber hose shut, start the truck,get up by your vicegrips or whatever is pinching the line just as the truck runs out of fuel and dies release the pinch on the fuel line,I mean the second it dies. The sudden rush of fuel under pressure will sometimes wash a piece of dirt out from under the needle. If it's just dirt under the needle,you just fixed it. Do you have a 3 port fuel pump or a 2 port fuel pump? 2 port doesn't get a check valve in the fuel filter, and I can see where putting the wrong filter in could cause a problem.
 
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Eighty5ov

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When I put the fuel filter nut back on, could I have over tightened it and crush the fuel filter?
 

fast 99

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Doubtful, spring filter then nut. Why do you ask?

Previous posts contain correct instructions. Was the float replaced? Fiber floats get heavy with age. Should never be reused. That's one of the Q-jet negatives. Some may disagree, brass floats are available, my experience they don't float the same as fiber.
 

Eighty5ov

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Does the spring on the needle matter ?
 

Ricko1966

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Does the spring on the needle matter ?
Depends on who you talk to as to whether you should use one.But if it's there it needs to be installed correctly, and it's not the way a lot of people think. Look for an internet pic.
 

Eighty5ov

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So I got a rebuild kit. Changed needle and seat. And airhorn gasket. Now on start up it’s shooting flames out the top
 

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