Fuel Shutoff Problems............

Muttley

Muttley

Senior Member
Hello out there in Ford Barn land it is I, your humble correspondent Muttley with another PITA problem. In the three years since Dad has owned his car (early '31) I've replaced the fuel shutoff valve twice. The first time was right after he bought it because the previous owner had installed a non stock twist open type valve. The second time, last Summer because the new valve was so tight we were afraid the tank would crack just from opening & closing the valve. Fast forward a year and we have the same problem plus this time the valve is leaking internally and flooding the carburetor when parked. I know I could just replace the valve again but a year from now we will be right back in the same situation. I'm also worried that removing and replacing the valve too many times will lead to leaks at the bottom of the tank. That is certainly something we don't want to deal with. Any suggestions on fixing this thing once and for all? The previous two valves were purchased from Sacramento Vintage Ford, does any sell a higher quality part or are they all the same?

And just in case you're interested here are the most recent photos, taken with the new interior:

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1. The most common cause of this problem is rust and/or dirt in the gas tank. When you replace the shutoff valve one more time I suggest that you install this filter in the valve.

http://parts.modelastore.com/show_Product.asp?ID=3884

2. This filter will prevent a lot of the rust from getting into the valve. The rust is an abrasive and chews up the valve and makes it leak and makes it hard to move.

3. When you install the filter you might notice that the housing of the filter raises the inlet about 1/4inch or so.

You might ask yourself "Self ... Why does this matter to me?"

Well the next time that you drain the tank there will be about 2 or 3 cups of gas which remains inside the tank and when you remove the valve the three cups goes on your new carpet!

So you might remove the carpet and floor boards or be ready to catch the gas!

Actually it is best to clean the rust and dirt from the tank and then install "finger" filter.

Some filters fit kind of loose in valve ... if so then "tin" the brass with some solder to make it fit tighter and press it in.
 
Last edited:
Benson said:
1. The most common cause of this problem is rust and/or dirt in the gas tank. When you replace the shutoff valve one more time I suggest that you install this filter in the valve.

http://parts.modelastore.com/show_Product.asp?ID=3884

2. This filter will prevent a lot of the rust from getting into the valve. The rust is an abrasive and chews up the valve and makes it leak and makes it hard to move.

3. When you install the filter you might notice that the housing of the filter raises the inlet about 1/4inch or so.

You might ask yourself "Self ... Why does this matter to me?"

Well the next time that you drain the tank there will be about 2 or 3 cups of gas which remains inside the tank and when you remove the valve the three cups goes on your new carpet!

So you might remove the carpet and floor boards or be ready to catch the gas!

Actually it is best to clean the rust and dirt from the tank and then install "finger" filter.

Some filters fit kind of loose in valve ... if so then "tin" the brass with some solder to make it fit tighter and press it in.
Click to expand...

This is right on, rebuilding an original shut off valve does not resolve the problem with rust creating a problem with the tapered seat design of the shut off valve.
 
The car has one of those filters in the valve, I installed it last year. I also put a new glass sediment bowl assembly and fuel line from from the sediment bowl to the carburetor. Despite the filter in the valve there are still flakes in the sediment bowl. For the life of me I cant figure out how the hell it's happening because the rust flakes in the bowl look much too large to pass through that extremely fine screen on the valve filter. If the fuel outlet on the tank ends up cracking or is in some way unrepairable without removal I would most likely install a tank in the trunk. The is no way I would even entertain the thought of pulling the stock tank out.
 
Nice stance, sitting just right. Put a ball valve in the fuel line to the sediment trap and turn the fuel off there and just leave the stock one on.
 
Redbird said:
Is it possible the gas lines had some crusty gunk in them if the car sat for a long time.
Click to expand...

No, I replaced the one from the sediment bowl to the carb and cleaned the other one out before re-installing.

Tom Wesenberg said:
It would have to be that, or the tank filter came out of place. Did the tank filter fit snug in the valve?
Click to expand...

The tank filter is still in place, it was extremely snug when installed, so much so that I had to use pliers to twist it in (yes, I made sure to check it afterword to see that it had not cracked). I have no idea how it's even possible for the flakes to get past the tank filter, it makes no sense.

Someday, if the car becomes mine I'll install a dual downdraft manifold, a pair of 97's, a Model T style tank in the trunk and none of this will matter. ;) :D
 
If You take the valve apart and use aircraft fuellube on it stop the leak and make the valve move with one finger
 
Muttley,
I know you don't like the hardware store pet **** type valve, but they worked perfectly for me & they fit perfectly in place of the original valve & they're CHEEP!---Tell Dad YO' for me.
Bill W.
 
The same problem for me, twice in 5 years, on both occasions I found a shard of brass had broken loose and was jamming the petcock, lifting it from its seat, the score was to deep to lap out, it didn't come from the tank and was not inline where the fuel passes thru, at $30 each I decided no more, and came up with what you see in the pics, so far so good.
 

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BILL WILLIAMSON said:
Muttley,
I know you don't like the hardware store pet **** type valve, but they worked perfectly for me & they fit perfectly in place of the original valve & they're CHEEP!---Tell Dad YO' for me.
Bill W.
Click to expand...

The hardware store special may be an option just so I don't have to screw with it anymore. Sorry it took so long to reply, that storm on Saturday night blew out my internet until about thirty minutes ago. We need to bring the old heap by your place so the A's can play together. ;) :D

Mike V. Florida said:
When taken apart, what does the valve you have in there now look like, scored?
Click to expand...

I haven't taken it apart since last Summer when it was replaced. The valve still works it's just stiff. I know whats coming though so I want to take care of the problem before it's completely stuck open/closed.

Brian T said:
The same problem for me, twice in 5 years, on both occasions I found a shard of brass had broken loose and was jamming the petcock, lifting it from its seat, the score was to deep to lap out, it didn't come from the tank and was not inline where the fuel passes thru, at $30 each I decided no more, and came up with what you see in the pics, so far so good.
Click to expand...

Thanks for the ideas, I'll be making a trip to the local old time hardware store soon. I'll report back with my findings.
 
It is always good to blow though any new valve from both directions with compressed air, just to make sure all shavings are gone.

My tank valve was hard to turn and leaked when I bought the car 22 years ago. I polished it on the lathe and lapped it with toothpaste. Then I gave it a light coat of grease before putting it back together. It's been perfect since and turns easy now.
 
I bot a repop from Snyders 2 years ago,works great..Question on indented firewall cars how to add extra fuel filter and still look correct ?? sc I know there is one at the carb.
 
I've installed the small filter into the indented tank valve and it fits and works fine. I've done it on 3 cars with no problems.
 
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