Fuel flowing back to tank after shut down

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1986ChrisK10

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Hey folks,
So I don't know if it is normal or not. But I noticed that the see thru filter that the gas appears to be flowing back to the tank. What gives, is this normal? I installed a new mechanic fuel pump. The truck did sit since 2009 and figured it would be a good thing to do while I was freshening up a few things. This back flow I would guess also would be the noise I hear, almost like a very small trickle of water from the carb vents.

Also, the Choke Light comes on and off while it sitting there idling. Is this normal too? I haven't been able to drive it yet. I put a new clutch slave in it and still no pedal pressure, so a new master will be here tomorrow.

Anyway, I am sure some are scratching their head. :shrug:

Thanks ahead of time.
 

firebane

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If fuel is flowing back to the tanks your fuel pump is bad. Choke light flickering could be due to oil pressure.
 

1986ChrisK10

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Thanks firebane, the truck starts right back up with no issue. Even sitting over night it fired right up. The fuel pump is brand new, I know that don't mean its not faulty. I've installed a many parts to find out they are junk.

The oil pressure seems to be accurate it goes up and down with RPM's. But I remember reading somewhere that the oil pressure sending unit and the choke are linked/powered together.
 

HotRodPC

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Does sound like the check valve in the fuel pump is allowing the gas to flow back to the tank. Not a huge issue really. If it's starting right up even after overnight, your carb well plugs must be sealed good and it's starting off of fuel left in the float bowls. If it's not a hard start problem, IMO it's a moot issue and I wouldn't lose any sleep over it at all.

I have the problem in my 84. If I let it sit overnight, I have to crank the hell out of it to get fuel back to the carb cuz both my check valve in the pump is bad and the well plugs in the carb leak and empties the float bowls.
 

bucket

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While the fuel draining back out of the filter may not technically be correct operation, it's fine in my opinion. I've had that happen even with new mechanical pumps.
 

1986ChrisK10

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Thanks guys for the info. So today while monkeying around with the hydraulics for the clutch, we noticed fuel still in the filter. So, I am willing to think that the check valve in the pump has freed up.

Thanks again for the info fellas.
 

1986ChrisK10

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Seems its the fuel pump, popped the hood today and its fuel soaked. Autozone strike again. :gr_guns:
 

bucket

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Seems its the fuel pump, popped the hood today and its fuel soaked. Autozone strike again. :gr_guns:

There's not much to them. Is it leaking between the two halves or is it maybe just a leaking fitting?
 

1986ChrisK10

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Thanks Bucket like always.
It was seeping around where the two halves went together. I went to Napa on my way home from work and bought their brand. Maybe I will have a little luck.
 

Camar068

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Thanks for posting this, I noticed this on my truck the other day....filter dry. But haven't seen it since. Have never seen it before on this one or the camaro so I was a bit concerned....but it fired right up.

Know what to change when it goes south.

Thanks again
 

1986ChrisK10

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darn it , it's doing it again Where are these well plugs? something some what easy to fix?
 

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