Carburetor Float valves

[TJMack]

Mike from Mike's A Fordable parts called me today. He said he has been in contact with other parts retailers and they are seeing the same problems with the Viton float valves. He also said they are collectively contacting the manufacturers to get the problem resolved. He said he would keep me informed. Maybe we can get an end to this hassle that so many of us have fought with.

[JD 1931]

I used new original type that I buy from Bratton when I rebuild my carbs. I don't trust any kind of rubber parts in carbs with corn crap gas...

[Tom Endy]

A number of years ago I bought several Viton tip float valves from Bratton. They leaked pretty bad so I took them apart and found them loaded with brass machine chips. I was able to clean them out and they worked fine. I called Walt Bratton and told him what I found. It should be understood that Walt, as well as other suppliers, are at the mercy of their supplier. Walt tried to do something about it by calling his supplier. The next batch I got were better, but not good.


Since then I always take them apart for inspection. Most often I find a few chips. The last batch I recently bought were very clean.


Quite often a leaking float valve is not the fault of the valve, the float is the culprit. Over the years people have been bending and tweaking and generally molesting the float trying to adjust the float level. This causes them to not come up straight against the valve. This pushes the valve off center and they leak. You never should attempt to alter the float in order to set the float level, do it with additional gaskets under the valve.


I have also noticed that the Viton tip valves I am getting from Bratton's lately have a slightly shorter needle. In order to make them work properly I have to put two black washers under the valve, where with a new valve and a new float one gasket used to do the job of setting the float level properly.


The gross ball valves don't work well with the gas here in California. They tend to stick closed. I had it happen to me while I was driving down the road (the engine quits and you coast to the side of the road). I have heard the same story from fellow club members.


Tom Endy

[smurph]

HELP!
I’ve tried everything (?) and can’t stop carburetor leak. Carb has been functioning properly for 5 years. Then, all of a sudden, at a stop, after shutting off the main gas valve, gas drips out from the carb to the pavement below.
I have tried four different float valves, including a new modern style from Brattons ( part # 14310). Still leaking. Float level properly set at 1”. Carb clean, jets clear, new main gasket. Why is gas flow not shutting off?

Thanks for your help
Smurph

[24ruxstel1339]

Did you shake the float and make sure no gas has leaked inside ?

[30 Closed Cab PU]

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Originally Posted by 24ruxstel1339

Did you shake the float and make sure no gas has leaked inside ?

If you have shut off the gas shutoff valve and are getting leakage gas out the carb, you may additionally have a leaking Gas Shutoff Valve. Disconnect the gas line at the carb, put a catch container under it. With the main Gas Shutoff Valve turned off, once the gas line is drained, no further gas should drip out the end of the gas line. Let it sit this way for a while, and recheck.
1st I would confirm the Shutoff is functioning properly/repair, and then figure out why the float does not seem to be seating properly.

[Bob C]

This is a long shot but see Marco's site.
http://www.abarnyard.com/workshop/carb-1.htm


Bob

[Dan Partain]

Here's what worked for me a few weeks ago. I experienced the same sudden leaking that you did (smurph). My carb had been running an original type float valve for many years.

I installed a 4 year old new viton tip float valve and it leaked worse than the original style valve I had just removed.

I removed the new viton tip valve and took it apart as Tom Endy had recommended (thanks Tom). It was easy, there is only a small plastic washer that holds the needle in the valve. It's easily removed and replaced if you are careful.

I didn't find any metal shavings in mine. I did find that the viton tip had a little bit of an oxidation or something on the surface of it. I took the rubber tip and spun it back and forth in a rag to see if I could refresh the rubber and remove the coating, and that did the trick. I also pushed the rubber around with my finger to make sure it was still flexible, and it was fine.

After I reassembled everything and mounted the carb I had no more leaks from that viton tip valve. I really prefer the old original style valves, but we'll see how this viton tip valve holds up.

[smurph]

Thanks for your replies. Still a mystery.
Main gas shut off valve working properly.
Put the float in container of gasoline— it floats, no sign of leaks.
Bob, thanks for the referral to Marco. I did that also. I had a small dimple— much less pronounced than in Marco’s picture, but I sanded it even.
Maybe a faulty float valve? But that doesn’t explain why the original one suddenly went bad!
Other than fuel overflowing the main and cap jets, is there any other way for fuel to find its way out the weep hole in the under body?

[30 Closed Cab PU]

Am not sre ther are other ways.


Did you just set the float in the gas, or did you keep it completely submerged?


The most common causes are in this string. If all the preceding are eliminated we have a mystery. Only suggestion is to swap in a known good seat valve, perhaps from another A, of if you have spare carb.



Thinking out of the box - plug the seat with a dab of flexible sealant, install it, see if the leak stops? Do not know if this is a valid test, see what others say.

[sjessen]

Sounds like most have had issues with leaks. I have worked on my 30' many times. I found a cure that works for me. I rev the motor up a little before turning the ignition off - no leaks. Not a real fix but works for me. Just tired of taking that carb apart and buying needles & seats. Steve

[Dave in MD]

Recently I had a problem with the viton tip valve sticking in the closed (float up) position.
Jeff at Brattons advised me to soak the entire valve in gas for two days. After removing it form the gas, the valve stem seems to move up and down without sticking in the closed position.
Dave

[JD 1931]

I prefer the original type float valve that was used in the Zenith when new , you can still get them new. I seat them before install and blow air to clean any particles out.

[jhowes]

How come the originals worked for 60 to 80 years and now we are experiencing problems? Can someone give a step by step procedure for preparing and installing the original type valve? Some have said to lap in the needle to the seat but how do you hold on to such small a small piece?. Jack

[jm29henry]

i really like the Grose ball type i have had good luck

[Ernie Vitucci]

Good afternoon...Jim has a good point as just a spec of rust, or other junk, that finds it's way into your carburetor can cause the float valve not to close all the way. Years ago and old Mechanic told me to put a magnet the size of a quarter in the little glass bowl of the fuel filer right up on the fire wall. Anything metal coming out of the tank will stick to the magnet. When the magnet looks dirty and has attracted a bunch of rust, then take it out of the bowl and clean it off...This has worked for me for years. I have also seen folks put a second old school glass bowl fuel filter down by the carburetor and put a magnet in it as well...that way the gas going into the carburetor is pretty much clean and will not foul the float valve. Ernie in Arizona