leak

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horchata81k10

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leaking gas through this hole -https://iscanner.com/sharing/45d88576
 

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fast 99

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That's the bowl vent. Probably high fuel level caused by heavy float. Rebuild should fix it.

Nipple usually has a hose to the charcoal cannister or is plugged with vacuum cap.
 

Ricko1966

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When does it leak? What fuel pump are you running? Any work done recently to the engine or fuel system? Fast is probably right on,but a couple other possibilities come to mind
 

horchata81k10

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https://iscanner.com/sharing/45d88576 -TruGrade Fuel / Fuel Pump from auto zone- last night it turned on fine and idled fine for about 30 min before i turned it off, this morning i turned it on and stayed on okay then i smelt gas and i saw it leaking a lot of gas.
 
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Ricko1966

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I am assuming the problem occured right after the pump change.Was this a 3 line pump or a 2 line pump? Did your truck originally have a 2 line or a 3 line pump? I no longer think a rebuild will help you.
 

horchata81k10

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it’s a 2 line pump and yes after the fuel pump change. but this morning yesterday night there was no issue
 

Ricko1966

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Okay. Was the original pump 2 line? And the replacement is 2 line? Is there a vent line not connected down by the fuel pump supply line at the frame?
 

horchata81k10

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here’s was the old old and here’s the new one it has 2 hoses connected to it. and i turned it on right now it was on for about 1 min and then it started to spill through the hole again and i shut it off and it leaked quite a bit of gas when i turned it off same hole (btw) i don’t know much about these trucks it’s my first one and i’m having trouble
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Ricko1966

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Look down by the frame where your supply hose is. Is there a steel 3/16 pipe that leads back to the tank? If it it has the vent tube running back to the tank put on a 3 line pump,so it can relieve fuel pressure back to the tank. If not check your fuel pressure, I'm going to guess it's too high and rises as the fuel expands blowing the needle and seat open. In which case it's going to be a game of musical fuel pumps,adding a deadhead regulator or adding a bypass. Personally I would add a bypass.
 
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horchata81k10

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you know what it might be a 3 line
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horchata81k10

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hm okay so change to a 3 line fuel pump first or is that just an option, how do i bypass it?
 

Ricko1966

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Changing to a 3 line pump is cleanest and easiest. By pass you'll have to cut the outlet line and buy a bypass regulator, or use a wix 30041 fuel filter if you can find one it will have a small bypass fitting with a restrictor in it. Or you can plumb in a tee straight leg from pump through to carbureator,dog leg of the tee will go to return line,you will have to make your own restrictor. I am using a fuel cut off valve for a lawn mower as my restrictor more open = more bypass,more closed=more pressure. At the shop I used to work at we just used a piece of brass and drilled a hole for a bypass,but don't remember the size. If you have a selection of carbureator jets at your disposal you could experiment with different size jets as a restrictor.
 

horchata81k10

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okay i want to change to a 3 line but i only have 2 hoses to connect would i connect a hose from where it’s leaking and to the fuel pump
 

Ricko1966

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Okay from post 10. I thought you had determined you needed a 3 line. I'm going to show you a pic of both hoses connected at the pump,same hoses connected at the frame side,and the 2 lines running down the frame. You need to see if you have the small line on the frame. Pic 1 pump side pic 2 frame side pic 3 and 4 tunes on the frame.
 

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