Gas Shutoff Valve

[nabbess1930]

I have a 1930 Model A pickup and can not get the carburetor to stop leaking gas over time. I always shut off the fuel and then let the truck run until the carb runs out of fuel.

I have replaced the shutoff valve with 2 different new valves from Snyder's and will still have leakage after the truck sits for a few days.

Any suggestions?

Thanks!

[rocket1]

try Brattons and then rebuild the carb so the float will shut the gas off.

[nabbess1930]

Ok, thanks. The carb was rebuilt not too long ago but I'll check it also.

[30 Closed Cab PU]

Originally Posted by rocket1

try Brattons and then rebuild the carb so the float will shut the gas off.

x2. Had this issue last year, learned from others on the Barn that repop shutoffs are notorious for leaking. Brattons are made in the US and warrantied for 3 years. Went through 2 repops from other places and they leaked, got one from Brattons and issue solved.

[nabbess1930]

Thanks for the replies. Am I correct that if I don't shut the fuel off it will keep feeding by gravity through the carb and eventually leak out? Or is there something in the carb to keep this from happening?

[Synchro909]

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There was a recent thread where a member had exactly this issue. Wish I could find it and repost what I said. It went something like; For fuel to be leaking from the carb, both the shut off valve AND the seat in the carb must be leaking. If either were working properly, there would be no leak. I suggest replacing the float valve and repairing or replacing the shut off valve. I favour repairing iot with this kit:
http://www.mikes-afordable.com/product/A9193S.html
at $1.60, it cost next to nothing and for a few minute's work, the job is done. I have used these kits and they work VERY well.

[nabbess1930]

So the float valve is what needs to be replaced in the carb? The entire carb does not need to be rebuilt? The truck is running fine.

[30 Closed Cab PU]

This is what I remember form my issues from last summer - details may be foggy.


Synchro - If I remember what I was told correctly, the kit only works on an original Shutoff Valve, not on repop/replacements?


Nabebess1930 - I agree both should not seep overnight. Of the 2 the float bol vlave can be the hardest on to get to operate properly. with a Full tank you have 10-11 gallons of gas/pressure that the this little valve is trying to seal/stop. Replacement float bowl valves are also iffy on if they will work. I do not remember the exact details, but some repop styles the needle can be removed, and the needle/seat can be cleaned out. Reports suggest that the issue is they are not sufficiently cleaned of machining debris. Same for the Shutoff valve - debris scratches the ball and housing around the ball in the shutoff.


Here a just of a couple of previous treads on the subject. If you search you will find more.


https://www.fordbarn.com/forum/showt...=leaky+shutoff


https://www.fordbarn.com/forum/showthread.php?t=250572

[30 Closed Cab PU]

You should try to confirm where it is leaking


The majority of the time a leaking carb is the float valve. When it is leaking check the very small weep hole on the bottom of the air intake, or when it is leaking feel the inside bottom of the air intake for gas - should be dry. This usually indicates float valve. When replacing the float level should be checked because if it is set to high it can cause leakage.


Then verfy that the bowl drain bolt is snugged/not leaking, check the fitting where the gas line attaches to the carb, insure the bolt that hold the two halves of the carb tighter is snug,, check where the 2 halves mate - if leaking there, there is a gasket there. Do not overtighen, you could damage things.

[duke36]

For the inside shutoff location, I remove the stock one, install a brass elbow into the tank, cut a small section out from the stock gas line and install a modern 1/8" ball valve with compression fittings.

[Synchro909]

Originally Posted by 30 Closed Cab PU

You should try to confirm where it is leaking


The majority of the time a leaking carb is the float valve. When it is leaking check the very small weep hole on the bottom of the air intake, or when it is leaking feel the inside bottom of the air intake for gas - should be dry. This usually indicates float valve. When replacing the float level should be checked because if it is set to high it can cause leakage.


Then verfy that the bowl drain bolt is snugged/not leaking, check the fitting where the gas line attaches to the carb, insure the bolt that hold the two halves of the carb tighter is snug,, check where the 2 halves mate - if leaking there, there is a gasket there. Do not overtighen, you could damage things.

If the carby continues to leak, obviously BOTH the shutoff valve AND the float valve are leaking. If either were working properly, the fuel wouldn't get through.

[ryanheacox]

+1 for the Brattons shut off. Had to run a die down the tank threads so it would line up correctly without over tightening but it works perfectly.

My carb leaks too and with the new valve I have no drips after one week.

[nabbess1930]

I greatly appreciate all of the help!

[nabbess1930]

I ordered a new Bratton's shut off valve, but which float valve do you guys recommend? There is a modern style and an original style.

[Ernie Vitucci]

Good Morning all...Walt Bratton also offers a 1/4 turn ball valve system that goes between the stock valve and the fire wall. With it, you never turn the stock valve again, just leave it open. I've had one for years. When I shut down for the day, I shut off the valve and idle for a couple of minutes and no leaks. If I forget to turn off the valve then I'll get a little carb drip overnight. You can find this system on page 62 of the 2017 Catalogue the 28/29 is part number 13330 and the 30/31 part number is 13350. Ernie in Arizona

[Corley]

OR, if you don't want to be bothered with fixing those items, and would like to never have to turn off the fuel shut off valve again, just install an electric fuel shut off in the gas line. Turns fuel on when key is on, turns fuel off when key is off (but won't work if you have a stock ignition switch). Costs less than $10 on Amazon, and you also need a couple brass fittings for the lines connections. (I just used simple 1/4" Farrell fittings if I recall.)

[nabbess1930]

I have a new Bratton's fuel cutoff and float valve kit on the way.

[Bill G]

While the carb float valve needs to be working properly, that is your first line of defense, but the fuel shut off valve should be absolute. It should not leak.

[30 Closed Cab PU]

Originally Posted by Magicbox51

While the carb float valve needs to be working properly, that is your first line of defense, but the fuel shut off valve should be absolute. It should not leak.

x2


As a comment for the Original Poster - With a real leaky float valve and a good shutoff it is possible to get a few drops of leakage as the gas line drains into the carb bowl. I noticed this on mine. This is the reason for the advice to turn off the shutoff and keep the motor running until the motor dies - empties the gas line and some of the float bowl.

[nabbess1930]

I appreciate the advice. That's what I always do when parking it for good, like over nite.


As a comment for the Original Poster - With a real leaky float valve and a good shutoff it is possible to get a few drops of leakage as the gas line drains into the carb bowl. I noticed this on mine. This is the reason for the advice to turn off the shutoff and keep the motor running until the motor dies - empties the gas line and some of the float bowl.[/QUOTE]