Farmall B Leaking gas at carb????? Very frustraited!!!!!!!!!

rjc2rjc

Member
Hello everyone. I am a complete noobie to the world of tractors let alone antique tractors. So please be gentle. lol
I have a 1944 Farmall B. It has the zenith carb on it. I rebuilt the carb on it. I checked all the ports. everything is open on it I adjusted the floats with it up side down to 1" 5/16". Everything is nice and tight. It all appears to be correct. So you know I have spent a couple days now reading posts on here about the floats and needles and seats. They are all brand new. I have tried several different things I have read on here.
If the tractor is just sitting it will not leak gas. But as soon as I start to turn it over it starts leaking gas out of the air intake on the carb. I have checked and triple checked the carb. everything is functioning as it should. But I can not figure out why its spewing gas out of it. it don't mater what position the choke is in it leaks gas. Can someone help me please.
:?
 
If the air cleaner is attached, the oil bath may be plugged up. If it is disconnected, the needle and seat may still not be closing properly. New is often as bad as old. If it has a rubber like tip on the new needle, I like to take a look at it to see if it has molding marks that would allow a leak (defects in the rubber surface). A magnifying glass may be needed for this. If it is looking good, I like to take a drill bit that fits into the seat hole (but not through the seat) and hand turn the drill backwards (not to remove metal, but to burnish the seat. Best of luck, and always shut off the fuel at the tank when the tractor is stopped. Jim
 
OK, does it leak while running. When you are cranking, gasoline is and has to be pulled from carb into manifold. If it does not immediately start, there will be some excess gasoline that does not make it up into engine. Slow cranking speed may be your problem. This happens on all carburetors but down draft carburetors don't show it as it goes directly into the engine. If it does not leak while standing, not running, or leak while running I say carb is ok. Also, do you have a packing in the drip plug hole. That drip plug is to slowly allow excess fuel to rid itself while shut down but if open hole gas will flow freely. A carburetor is a rather crude device to say the least as you can make an engine run by just squirting gasoline in with a oil can.
 
I am still trying to get it running. It fires but not every time. It does turn over slow no matter what battery I hook to it. so maybe that the issue. I don't know. like I said im new at this
 
Still 6 volts or is it now 12 volts can make a difference as how to fix it?? Things to try
#1 turn the gas on count to say 20 then turn it back off and try to start it. If it starts quickly turn the gas back on
#2 check the spark. It needs to be a blue/white in color and jump a 1/4 inch gap or more.
#3 pull the starter and have it check to make sure it is in fact good and not dragging or pulling to many amps so as to rob the spark of power.
#4 when is the last time you serviced the oil bath air cleaner
 
My M does that if it is very cold and I give it choke to start with.
They don't usually need choke to start, but may need it to keep
running when very cold. The battery I have in it doesn't have a
lot of CCA so it spins slow. I think you are fine. Adjust it two
turns out to get it to start and go from there. If you don't have
the air cleaner hose on it put your fingers over the inlet of the
carb restricting it a little bit to get it to draw in the fuel. Don't
run over yourself!
 
Get the starter serviced and make sure you have 1ga cables and they are good. The starters on those engines will turn them over great if things are in shape. Doesent cost too much for cleaning the commutator and new brushes and maybe bearings
 
Since your starter is turning kinda slow and gas is coming out somewhere it shouldn't, can I ask is this tractor someplace warm while you are trying to start it or are you trying to get this going in a cold garage or shop in the north country here?
 
While you have the starter off being tested and probably for some refurbishment get some new battery cables made up at a good auto parts place. I have found using 00 size cable and soldered terminals have fixed starting problems on all of my 6 volt letter series Farmalls. Attach the ground cable to one of the starter mounting bolts making sure you have very clean and bright connecting surfaces and hardware. Keep the cables as short as possible with enough length for easy connections. Same thing for the cables to the starter motor. I also generally use external tooth washers at the non-battery connections to get an extra good bite into the metal or contact surfaces. I don't recall if you have a 6 or 12 volt system but this is really needed for the original 6 volt systems, Hal.
 
Might be a problem. Maybe not turning over fast enough? Vapors condensing on the way up and the gas running back down flooding out the carb? I'm only an average mechanic but can tell you that starting these old updrafts in cold weather requires everything to be working up to spec. If you can get a heater in there and warm things up, try it again and see if it works better. Just a thought.
 
Well both of my farmall being an h and
cub, leak when shut down. When the engine
fires the leak immediately stops. Even
rebuilt carb on the cub because it leaked.
No change at all. Any farmall I seen
changed to 12v will sure spin the engine
if everything is right. Gotta be careful
sometimes though so not to burn up that 6v
starter.
 

Some of the overhaul kits that I have used, especially NAPA, do not have the bowl vent hole punched in the gaskets, which will cause the bowl to overflow when the engine is not running. I've found this same problem several times. Carefully check your gasket against the carb body to be sure the vent isn't plugged.
 
Hook up that air cleaner hose so you don't lose all those vapors & when it fires, it may take off. Don't use the choke for more than 1 or 2 compressions.
 
I have started my Super C in extreme cold with the hand crank. Could barely turn it over. Full battery voltage to the coil fired it up. These engines don't need to spin like a diesel to start.
 
I think you are missing my point. We don't know what kind of compression he has and it is turning over slow. I have had some with that were on the low end of compression that would never start in the winter. I don't want to argue the point, just an idea to put out there. Not like it doesn't happen.
 

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