Fuel drain back

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4UDAD
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Fuel drain back

Post by 4UDAD »

After sitting for a week or so my stock 440 is hard to start, I have determined that all the fuel is draining back to tank. Just wondering if any of u have delt with this issue and what the solution was. I tried my local parts store and got the usual response, I still know more than them. Wondering if anyone knows of a fuel filter with a check valve or just a check valve I could put in line.

Thanks in advance.

JimE
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Re: Fuel drain back

Post by JimE »

That is quite normal with carburated vehicles, most do not have a closed fuel system. Jim

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Jims68
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Re: Fuel drain back

Post by Jims68 »

JimE wrote:That is quite normal with carburated vehicles, most do not have a closed fuel system. Jim
I was wondering.... is it really draining back into the tank, OR could it be possible that it isn't draining back but evaporating from vapor lock (I think that is what it is called?) Just wondering....

Jim

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Re: Fuel drain back

Post by 712edf »

4UDAD wrote:After sitting for a week or so my stock 440 is hard to start, I have determined that all the fuel is draining back to tank. Just wondering if any of u have delt with this issue and what the solution was. I tried my local parts store and got the usual response, I still know more than them. Wondering if anyone knows of a fuel filter with a check valve or just a check valve I could put in line.

Thanks in advance.
Check with a place that services boat engines. They might could rig up something.

Bucky

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Re: Fuel drain back

Post by PwrWgnDrvr »

It is most likely evaporating thru the float bowl vent or draining into intake manifold thru a leaking gasket on the carb.
It is impossible to drain a carb back into the tank below the level of the needle valve. Once the fuel reaches that level, any siphon action that could possibly exist will be broken. If u have a Holley carb on it, they are notorious for leaking float bowls.

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gp-az
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Re: Fuel drain back

Post by gp-az »

I installed a Carter inline electric fuel pump to help in those situations.Saves on long engine cranks.GP

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WD
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Re: Fuel drain back

Post by WD »

Mine is the same way, but only takes a day or so. I get tired of having to prime the carb via gas can every time I go to cold start it.

Check your fuel pump, I had one do the same thing before and the gas was draining into the crankcase. Via the fuel pump.

Need to change mine again, cheap fix. Lasted for about 6 years.

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