I installed an accessory fuel shutoff valve several years ago which I purchased from one of the part suppliers. It works great and I like the convenience of opening the hood instead of crawling under the car. This morning, I went out to the garage and smelled fuel. Looked underneath, and sure enough, there was a big blotch on the cardboard right underneath the carb. It appears to me that the shutoff valve is leaking from the top where the petcock goes through the body. Wiped it dry, and within minutes, it had a gas sheen on it. It leaks in both the open and closed position.
Does anyone have any experience with this particular valve? Can it be taken apart? Is there any packing? There is a spring and clip on the bottom part of the valve that cannot be seen in the picture.
To make matters worse, I just filled up yesterday so I have a tank full of gas and no way to shut it off if I want to remove the valve. My sediment bulb petcock leaked badly so I lapped it and soldered it in a fixed open position.
Any suggestions for a fix?
Dan ; I have good results with a MODERN ball valve
I have those on two of my cars. No problem with either of them. When they wear out I don't think you have any choice but to buy a replacement, or not.
You can also buy a ball valve in 1/8" NPT from a local hardware store a lot cheaper. The setup in this picture cost about $15.
Fix the original valve, too.
You should never, ever have a gravity fed fuel system whose only shutoff is at the carb!
That's where most fires start...
All you could do then would be to push it away from other things and take video of it burning.
Anthonie's quarter turn ball valve is the ultimate answer, and it can be hidden in the frame rail so it won't show.
Dan -- You probably can get it to hold gas again by using some aviation fuel lube on the working surfaces. (That product is available from Aircraft Spruce, or now from some of the Model T parts vendors.) To do that, you'll need to drain the gas from the tank, like it or not, which of course you wouldn't need to do if you had a working sediment bulb. While you have the tank emptied, it would be a great time to replace/rebuild that bulb.
Looks like a plug valve, it can be taken apart and lapped, but a modern ball valve would be better.
Try spinning the shut off lever back & forth a few times. If it's spring loaded on the bottom lift it once or twice while rotating it. Some times they re-seat nicely. You can lap it as suggested but if it doesn't seal a replacement is a better option.
I have a shut off valve at the carb which I shut off in the driveway while the car is running and let the engine use up the gas in the carb bowl until the engine stops. Then I hand roll the car into my garage where my gas water heater happens to be also. This way there is no gas on the other side of the shutoff to leak out of the bowl and give my home owner's insurance agent gray hair.
BTW. Bite the bullet and fix your sediment blub, you will sleep better.
Couple thoughts may have been referenced.
1. Lap the valve with yellow Timesaver, don't use valve grinding compound usually found at local auto parts stores, its too coarse.
2. Try spreading dry soap from a bar of hand soap on the parts. Sometimes that will do the trick. You can probably get it to work.
Those old style valves really look good and are worth the effort to save.
Has nobody come up with remote control for the sediment bulb valve?
My Fronty has a high mounted carb, so I don't have the gravity leak risk.
Have you tried simply spinning the lever back & forth a few times to re-set the taper? If it's spring loaded on the bottom lifting it a number of times while turning it can re-seat it too. it may be worn but it could be a bit of grit giving you a problem. this is the easiest thing to do. Lapping is a possibility but you seem to have had no luck with that on the bulb so maybe a replacement is a good idea. Just don't hide it that only leads to not using it.sing it.
What the hell happened there? First post didn't show so I did it again then both were there. Shades of MTFCI!
I'd opt for lapping with yellow Time Saver, then using the aviation lube like mentioned above. With plug valves, I always use downward pressure while twisting them. It may not be needed, but the plug being seated down into the valve is what seals them, so I give them a little headstart.
Here is a cute solution on an unrestored '25 coupe that was at the Farmington Model T meet two weeks ago. A porcelain lever from a gas stove. The other end of the rod hooks onto the original stock valve handle similar to a universal joint.
You don't have to get on one knee or open the hood.
Erik, I LIKE THAT!!!!!
Great idea, and it looks down on the farm era correct.
I wish I had taken a photo under the car where the rod meets the valve. I also wish I had taken a photo of the entire car.
How to get the gas out of the tank: with a suitable container below, open the petcock on the bottom of the carburetor. I agree, while you're working on this fix or replace the sediment bulb valve.
If rotating the handle several times around doesn't assist in re-seating the taper, usually a very SLIGHT tap on the handle top will seat the taper to prevent anymore leakage - only drawback is you will need to pull the handle UP slightly to rotate it again.
How to get the fuel out of the tank?
As Steve said, open the line and drain it.
Siphon it out of the tank either the old fashioned way or the new pump in line hose.
Or, just raise the front of the car so that the carb is higher then the top of the gas tank. Probably the simplest if you have a method to do it. Kind of like this without the auxiliary tank:
I have found that it is very easy to pop the front floor board and reach under the floor to the shut off handle.
I have replaced all of the brass antiquish shutoffs on my cars with the modern ball type. They require a quarter turn and unlike the brass ones, I don't need a pair of pliers to turn them. It seems that when ever the brass ones got about a year old I could not turn them without pliers. I tried using the expensive airplane valve lubricant and moved them back and forth. I tries taking them apart and used valve seating compound and lubricant and moved them back and forth. Finally got sick of the problem and started using the little ball type and have not had the slightest problem with leaking and movement.
Always have a good valve at the gas tank. Even if you do not use it every time you park the car, it is necessary if you want to work on the carburetor. Also necessary in the very case cited above if the accessory valve either won't turn or leaks. The float valve in the carburetor should also be in good condition so that if gas leaks by either the original valve or the accessory valve, it won't also leak at the carburetor.
When I park in the garage, I put a tin can under the carburetor just in case. If you do catch some gas in the can, you can use a funnel with a coffee filter in it and pour back into the tank.
Those accessory brass valves seem to last a couple of years and then either get very hard to turn or they leak.
When I'm browsing through Snyder's catalog quite a few parts meant for the Model A might suit my T's too..
Anybody tried their electric fuel shut off?
The solenoid type valve lets gas pass only when it gets current. Wouldn't work connected to the battery ignition on a T when you switch over to magneto, so a separate switch would be needed - still more convenient than shutting off under the hood or under the car..
Pictures? Where you found a ball type valve that works?
You can order a ball valve from Restoration supply....they work great and do not leak. They are more expensive than standard valves.....compared to having a fire, they are cheap insurance. Much easier to turn on and off compared to other fuel valves that I have used.
Thanks everyone for the helpful feedback and ideas. I understand that there are definitely better designed valves available on the market. I decided to use the one I have because the styling and construction of it makes it look like it belongs there to the untrained eye.
It is a spring loaded valve as some have mentioned. In the open position, I can pull the handle up out of the body itself. I tried doing this several times, but t did by seem to make much of a difference. There really is no valve seat that it rests in; its more like a straight barrel. I do not know how it seals other than the friction with the body itself.
When I end up removing it, I'll take it apart and post pictures.
Next question! Is that a true petcock/drain on the bottom of the NH carb? It looks to me like if I unscrewed it, it would just drop the bowl. Can I open that valve in order to remove gas in a controlled manner?
"In the open position, I can pull the handle up out of the body itself."
The rotating part of the valve and the hole it fits into are both tapered, and the spring should apply enough pressure on the rotating part to seal it against the outer housing. If you can pull it up by hand, there is not enough spring pressure. Time for a new spring. As I mentioned above, the fuel lube helps to seal it, and it also lubes it making it easy to turn.
The drain on the bottom of the carb is a two-piece part. If you unscrew the whole thing, it will release the bowl. If you unscrew only the T-shaped center part, it will leave the bowl in place and allow gas to drain.
Thanks Mike. I should have stated that the rotating part of the valve pulls up VERY easily out of the valve body, each time spitting out some fuel. I took a picture from the parts website so that you can see the bottom in detail. A new spring should do the trick. Guess I'll remove the old spring and head to the hardware store. Hopefully I can find something close.
I also forgot how much I paid for it originally. I've got to try and fix it.