Carburetor still flooding on TO-35

[WilliamTO-35]

I've posted this issue before, but the answer still escapes me. The Carter UT carburetor on my 1955 TO-35 floods unless the engine is running.
I've cleaned and inspected the carburetor and floats, adjusted them, and replaced the needle and seat at least 5 times over the last few years , but it still floods. I have to turn the fuel petcock at the carb. inlet on just before I start the engine, and off just after I stop the engine. I tried tapping on the Viton tipped needle to seat it ( as suggested on this forum) but the problem remains. I resurfaced the cast iron under the float seat gasket, but still no improvement. The float does have a " helper" spring to put more pressure on the needle . I never had this flooding problem until the carb. parts started coming from China , which was several years ago. It may or may not have coincided with the introduction of alcohol into the fuel. I've rebuilt and repaired many carburetors over the years, but this problem has me stumped. I'd like to try a different needle and seat than is supplied with the rebuild kits, but finding one that fits would be difficult. I suspect that the needle does not fit well with the seat , for some reason. My fuel is fresh, and my fuel filters have always been rated at 10 microns. The fuel is a gravity feed , and using fuel from a temporary can instead of the gas tank didn't help. Anybody have a suggestion ?
Thanks !

 

[Oldtractorfixer]

Are you sure you don't have a bad float?

 

[super55]

I have an old Oliver Super 55 that will flood out as well if the fuel line is left open after shutting down. It has a glass bowl shutoff directly below the fuel tank that I can reach while sitting down.

My Avery has the same setup.

I think a lot it has to do that these are gravity fed fuel systems so there is always fuel pressure against the needle valve. If I leave the shutoff open for more than an hour on either tractor with it off I can usually see fuel leaking from around the carb.

I would just make a more easily accessible fuel shutoff than keep tinkering with the carb if it is running good.

 

[WilliamTO-35]

Thanks for your replies . Yes, the floats don't leak , and are not rubbing anywhere inside the float chamber. ( I once had a flooding problem on another engine, and it turned out that the float chamber air vent had been plugged by mud wasps, and the pressurized air would not let the float rise up enough to seat the needle.) At this point, I may rig up a remote fuel shutoff as super55 suggests that I can operate from the driver's seat.
I don't care for having to start the tractor while standing next to it , or step off of the tractor while it's running. Getting run over by my own tractor is, at the very least, poor form !

 

[slantsix]

How about one of these wire to the ignition, available in 6 or 12 volt.


Model A Ford Economy Electric Fuel Shut-Off Valve | Snyders

 

[WilliamTO-35]

True, an electric fuel shutoff that close couples to the carb. inlet is certainly an option.

 

[MatthewPaul]

Silly questions.

-When you set the float height, did you set it off of the gasket face or the carb face?

-And, when holding the carb upside down and the float,needle, and seat installed - can you blow air through the fuel inlet portion of the carb?

 

[WilliamTO-35]

As I recall, the float level setting is done with the gasket in place. I've tried several different float settings , including an effort to keep the fuel level in the bowl lower than normal to put more pressure on the float needle as the floats become submerged due to leakage. Nothing works long term ( more than a day or two). On the bench , the needle seals well when blowing air through the fuel inlet. Before I start up the engine this month, I think I'll try to find another brand of inline fuel filter . I've had trouble finding reliable data on some filters that shows the micron filtering rating . I try for 10 microns.

 

[Looking4new]

It sounds like your only other option is to shut the fuel off EVERY time you shut the engine off.

 

[MatthewPaul]

As I recall, the float level setting is done with the gasket in place. I've tried several different float settings , including an effort to keep the fuel level in the bowl lower than normal to put more pressure on the float needle as the floats become submerged due to leakage. Nothing works long term ( more than a day or two). On the bench , the needle seals well when blowing air through the fuel inlet. Before I start up the engine this month, I think I'll try to find another brand of inline fuel filter . I've had trouble finding reliable data on some filters that shows the micron filtering rating . I try for 10 microns.

Ah, I got ya. All of our old tractors are the same exact way. I had always assumed that was how they were, and shut the fuel off at the tank when I am done with them.

 

[DJ54]

I did a quick check, and looks like that carb had a drain plug in the bowl, and just guessing it's 1/8" NPT. I read a thread several years back, on a fellow having the same problem. To get the float set to where the fuel level was correct, although not to specs., he removed the plug, and installed a barbed fitting. He then slipped clear tubing on the fitting, long enough to turn up 180º along side the carb., a good bit above the fuel level. Then, turning the fuel on, will allow you to see the fuel level inside the bowl. Just keep tweeking the float, until you have the proper level. Once you have the float set, you can always leave it set for a while, and check to see if it's letting fuel by the needle.

I know back in the 70's when I was showing tractors, nearly everyone had to reset their floats, due to the different specific gravity of the unleaded fuel. I have to think that adding ethanol has to change it even more.

 

[PILOON]

Could your problem be alcohol in gas? (ethanol)

If the carb kit came from offshore they might not be using suitable rubber components and if so the seat or seals would deteriorate rapidly.
Also is there any rubber fuel line sections?

 

[WilliamTO-35]

Piloon- Yes, I am using a rubber fuel line section , which feeds gasoline from a 4 gallon outboard motor tank that sits on top of the hood . ( The original gas tank was badly rusted through, and was beyond repair.) The rubber fuel line is of recent vintage, and is sold as being tolerant of ethanol in the gasoline.
Since a new needle and seat tend to last two or three days before causing flooding , it may be that the Chinese version of a " Viton" tip is not tolerant of alcohol. However, this flooding problem has been going on for about 15 years , and by now the "Viton" tip should be of a correct material.
I may sort through my collection of old carb. parts ( I never throw anything out ) and try to find a seat and needle for this carburetor that is not polymer tipped.

 

[fried1765]

Piloon- Yes, I am using a rubber fuel line section , which feeds gasoline from a 4 gallon outboard motor tank that sits on top of the hood . ( The original gas tank was badly rusted through, and was beyond repair.) The rubber fuel line is of recent vintage, and is sold as being tolerant of ethanol in the gasoline.
Since a new needle and seat tend to last two or three days before causing flooding , it may be that the Chinese version of a " Viton" tip is not tolerant of alcohol. However, this flooding problem has been going on for about 15 years , and by now the "Viton" tip should be of a correct material.
I may sort through my collection of old carb. parts ( I never throw anything out ) and try to find a seat and needle for this carburetor that is not polymer tipped.

If you think ethanol might be your problem, you could go to your local airport and buy 100LL (100 octane low lead) gasoline.
I use only 100LL in my 1951 8N, and it certainly seems to enjoy it.

 

[shaeff]

I'm not sure what part of the country you reside, but here in the northeast we have Stewart's gas stations that carry 91 octane, ethanol free fuel. I had a problem with the ethanol killing the carbs on my mowers, weed whackers, and had the same issue with my MF35. I would shut the engine down and fuel would quickly begin to pour out of the carb.

I rebuilt the carb the same way as the first time, used a USA kit made and shipped from CA. No more issues after switching to ethanol free fuel. Same deal with the mowers and weed whackers.

Of course, your mileage may vary.

 

[coss]

I'm not sure what part of the country you reside, but here in the northeast we have Stewart's gas stations that carry 91 octane, ethanol free fuel. I had a problem with the ethanol killing the carbs on my mowers, weed whackers, and had the same issue with my MF35. I would shut the engine down and fuel would quickly begin to pour out of the carb.

I rebuilt the carb the same way as the first time, used a USA kit made and shipped from CA. No more issues after switching to ethanol free fuel. Same deal with the mowers and weed whackers.

Of course, your mileage may vary.

I live just across the river from your Germantown location, and Stewart's ethanol-free gas is all I use in my MH 50, chain saw, lawnmower, leaf blower, etc.

I've also gotten into the habit of turning off the engine by shutting off the fuel valve and letting it run out of gas. In addition to the gas choice, it may be overkill, but it keeps the carb out of trouble.

 

[shaeff]

I live just across the river from your Germantown location, and Stewart's ethanol-free gas is all I use in my MH 50, chain saw, lawnmower, leaf blower, etc. I've also gotten into the habit of turning off the engine by shutting off the fuel valve and letting it run out of gas. In addition to the gas choice, it may be overkill, but it keeps the carb out of trouble.

Right on, I love it. Much easier than buying an additive to "neutralize" the ethanol.

I used to do the same with my MF35 Utility, run the gas out of the carb, but it takes too much cranking to get fuel back in the bowl so I just turn it off and kill the fuel at the tank in case the needle and seat fail. (Don't want 8gal of gas pouring out in the yard)

You in the Saugerties/Malden/Catskill/Palenville area?

 

[coss]

Right on, I love it. Much easier than buying an additive to "neutralize" the ethanol.

I used to do the same with my MF35 Utility, run the gas out of the carb, but it takes too much cranking to get fuel back in the bowl so I just turn it off and kill the fuel at the tank in case the needle and seat fail. (Don't want 8gal of gas pouring out in the yard)

You in the Saugerties/Malden/Catskill/Palenville area?

Saugerties.

 

[fried1765]

I'm not sure what part of the country you reside, but here in the northeast we have Stewart's gas stations that carry 91 octane, ethanol free fuel. I had a problem with the ethanol killing the carbs on my mowers, weed whackers, and had the same issue with my MF35. I would shut the engine down and fuel would quickly begin to pour out of the carb.

I rebuilt the carb the same way as the first time, used a USA kit made and shipped from CA. No more issues after switching to ethanol free fuel. Same deal with the mowers and weed whackers.

Of course, your mileage may vary.

No ethanol gas in THIS part of the Northeast!
Massachusetts does not permit the sale of ANY ethanol free gas.
I buy 100LL at the local airport, but it is pricey, and I really would prefer it without the lead!

 

[shaeff]

Saugerties.

Nice, I spent a few years dating girls in Saugerties when I was a bit younger. (33 and married now) beautiful area

No ethanol gas in THIS part of the Northeast! Massachusetts does not permit the sale of ANY ethanol free gas. I buy 100LL at the local airport, but it is pricey, and I really would prefer it without the lead!

Ah nuts!