Carburetor Float valves

[TJMack]

Would I be more apt to get a valve that doesn't leak if I tried a Grose style float valve instead of the Viton tipped ones? I've gotten two of the Viton ones from Mike's A Fordable Parts and they both leak worse than the one I'm trying to replace. That one will occasionally stop leaking, but the new ones both would let the carb drip continuously.

[chap52]

Give Mike's a call. They may need to take a look at them. Most vendors appreciate the "head's up".

[Jim/GA]

I have had great performance from the viton tipped valves in the past. I suspect the gasket(s) used to install the valve in the carb are not sealing properly. Try adding a light coating of a non-hardening sealant (like Permatex #2 or Hylomar AF) to the gasket(s) and reinstall.

Re-check the float level when you do. The lubrication of the sealant will allow you to tighten the valve more, resulting in a higher float level than you had before. It does not hurt anything to set the dry float a tiny bit over 1 inch; better than a bit under 1 inch.

Feel free to contact me with any questions (email below).

.

[TinCup]

I have a Viton tipped valve in my 31 and have had for over 6 years. I do not have the leaking issue some have reported with them. The gaskets as Jim has suggested can also be the cause. Oh and by the way I do run Ethanol gas.

[johnbuckley]

Originally Posted by chap52

Give Mike's a call. They may need to take a look at them. Most vendors appreciate the "head's up".

x2. No particular type is problem free...I have come across rogue valves in all types... ball, conventional needle and viton . (And had Viton ones sticking closed)

[Fast31]

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Check every float valve with a manual vacuum pump. If they hold vacuum they’re good. I had 5 leaking, including 2 new ones! Then I got me a viton tipped one and that held vacuum and did not leak fuel.

[Wick]

Put your float in some gas and make sure it doesn't have a hole in it.

[Crankster]

Replacing both valve & seat correct? Not to sound patronizing but let's be clear. They are a matched set and (should) be replaced as a pair. Some may not know this.

[TJMack]

Originally Posted by Crankster

Replacing both valve & seat correct? Not to sound patronizing but let's be clear. They are a matched set and (should) be replaced as a pair. Some may not know this.

The two pieces come as an assembly. It's difficult to even take them apart if you want to lap them.

I'm pretty sure it's the valve assembly that's leaking, not the gasket. At one of the times when it wasn't leaking I took out the old valve and put in the new one. I even used the old gasket to eliminate that question. When I put in the new valve it leaked as soon as I turned the gas on. I then changed back to the old valve and it didn't leak. I therefore concluded that it must be the valve. (this was with the second new valve)

I talked with Mike's after the first valve leaked. They're great to deal with. They sent me the second one right away. I hate to keep bugging them, but I guess I'll have to.

From what Fast31 and others have said, it sounds like this is a common problem. If you're lucky enough to get a good valve you never see it.

Right now the old one is holding quite well. I left the tank valve on for about 6 hours today with no leak. But I know it won't last.

The car runs great, and I always shut the tank valve off anyway, but it's just not right.

[Jim/GA]

This may or may not have been the problem with your float valves...

Any little speck if rust, dirt, etc., that flows down with the gas and gets trapped between the needle and the seat will cause the valve to leak (not shut off). Debris can actually get imbedded in the viton tip, making it not seal and also not flush out with gas flowing through the valve.

So it is a good idea to open the gas valve and flow some gas out of the fuel line (catch it in a clear glass so that you can see what's in the gas). Then connect the fuel line to the carburetor and go.

I hope this helps.

.

[kimlinh]

I had nothing but trouble with the new viton tipped( and old style) float valves. The two ball grose style valve did the trick. What ever type you use make sure it is working properly. The danger of fire should not be played with, even with the tank shut off valve. I don't know why the needle and seat type valves did not work as good as the grose jet type but they didn't.

[Benson]

New valves may have brass shavings inside from machining.

1. Before installing, blow 30 pounds pressure air backwards through the OPEN valve for 15 seconds or so.

I say 30 pounds because that is the pressure of an "OSHA safety" regulated nozzle.

2. I suspect that if 100 +pounds were applied to Viton valves that the plastic retaining ring might be blown out of the valve.

3. Also installing a "finger" filter in (the gas tank shutoff valve) keeps dirt and rust out of the float valve. Which is a common cause of float leaks

4. The finger filter keeps Dirt and rust from getting inside shutoff valve which makes it hard to turn and wears it out.

[Bikerider58]

I have the same issue with a new Viton valve. Took it apart to clean and noticed two things

1. Viton tip is hard, like a coating on the metal or plastic. I expected more of a rubber like material. Softer stuff works great in bike carbs.
2. The body does did not have a face for the needle seat. It is sharp edge.

I got my Viton from Bratton’s and told them of the issues.

This weekend I may try using an original type needle to tap in a seat.

Oh, The Oring type worked fine.

[w.michael]

I have had three viton tipped float valves. The first one leaked. The second stuck in the closed position every time I stopped at a stop light. The third one is still in my car. It has not leaked yet, but it has stuck in the closed position one time. If it begins to stick more frequently, I'll have to change it out again. I'm not sure if any other valve is any better, but the viton tipped valve certainly isn't very reliable.

W. Michael

[duke36]

We've been adding ethanol stabilizer to help with the effects of this gas on seals, etc.
which perhaps is softening the viton tips.

[TJMack]

Yesterday I talked with Mike at Mike's A Fordable Parts about he problem I've been having with the Viton float valves. Nice Chap.


He said that he hasn't heard of problems with these, but I should contact the fellow (named Charlie in Kentucky) that does most of his carb rebuilds and then call him back. Charlie said he has also been having a lot of trouble with these valves and was planning on calling Mike himself.


When I called Mike back he was amazed that Charlie hadn't spoken up before since he had about 15 bad ones on hand. Mike is going to look into the problem and get back to me when he has it resolved.

[stouchton]

I had 2 vitons from Brattons refuse to seal.

Installed a grose style and all has been well - going on a year now.

I have 7 other carb engines all with viton and no issues at all. Must be a quality issue with the ones for the A's.

[Chris H]

When installing any new float needle and seat, (or old, for that matter), I check by installing the float, rolling the carb over so the float is resting on the needle. Hook up a Mity Vac hand pump in, pressure mode, (not vacuum) and pump up with air. The needle should hold a steady pressure of about 7 PSI or more. Note: a vacuum will pull the seat tighter and cover up a faulty seat. I have been using this method on small engines for years and never had a leaker yet. The hard part may be making an adapter for the carb inlet.

[larrys40]

Originally Posted by Fast31

Check every float valve with a manual vacuum pump. If they hold vacuum they’re good. I had 5 leaking, including 2 new ones! Then I got me a viton tipped one and that held vacuum and did not leak fuel.

I check all of them with a hand held vacuum pump. I buy them a dozen at A time or more and honestly if 7 are ok that’s about the average, and that’s with the Viton tips units. I did a carb yesterday that had A unique shape but it was viton and it was awesome. Jim, I must not have as good a luck as you. I know it’s nit the gaskets because the valves them selves not installed won’t hold vacuum. Just my experience and I’m a pretty tentative rebuilder/restorer .

Larry shepard

[Jim/GA]

While i have had good luck with the Viton tipped needle valves in the past, they might be coming from a different supplier now.

I have also used the Grose ball-style valves on my Model B carb with great results. So switch to them if the Viton needles don't work for you.