gas in crankcase oil

Tdefreece

New User
I have a 49 farmall c. I keep getting gas in my oil. I have rebuilt the carb and adjusted the float and pretty sure the nee dle valve was seating. Finally put on a new carb and still have the same problem. help

thanks
 
If it runs OK and seems fine while starting, the easiest way fuel can get in the crankcase is to have a leaky needle and seat
in the carb that can allow the fuel to rise above the height of the intake ports and flood the engine. To stem this, shut
off the fuel at the tank every time the tractor is shut off, even for a minute or two. Jim
 
Your problem is why we tell people to shut off the gas at the sediment bowl when ever you park a tractor. Does not matter what tractor it is. I have a lot of tractors and on all but one or 2 I shut them off each and every time I shut it down.
 
If your fuel system is letting enough gas past the float valve to get into the engine and oil, the intake manifold would have to be completely full, and there is no way you would ever start it. Rather than fuel you probably have the seal/o-ring on the touch control pump leaking hydraulic oil into the crankcase and diluting the engine oil. My cousin had the same problem with a cub, which has a similar fuel and touch control setup. He also thought it was fuel in the oil, but when he put new seal in touch control pump, all was well.
 

it seems to run great. I made it a point to keep the gas shut off even put on a new gas valve at the tank. I changed the oil after I put the new carburetor on and run it a few minutes and oil looked good. went out this morning checked the oil and it looked good. then I drove it around for about 45 minutes, checked the oil later and it had gas in it. have not tried to do anything with the float on the new carb.
thanks
 
i had one of my 2hundreds ,which is just like your c...when i cut the bowl off ,,,the next time you would go out there the oil bath was full ,every thing was full....cut off was leaking...i still pull off the gas line to carb and stick it thru the hood latch,,,i guess its time to buy a new bowl ....might want to check to see if its getting by the shut off..........if that aint it ,,,,i agree with others it could be pump seal...mine was leaking an my first thought was gas but it was the pump........dewy
 
If it was running there is no way known to me to get fuel into the crank case. It would be so flooded that it would quit. Remove the line from the carb with the valve shut off. If it drips out after 5 minutes, the new sediment bowl is not closing. Jim
 
Maybe you posted this before you could finish your reply. Are you asking what the "bowl" is or
"sediment bowl" I'm sorry if I am stating something obvious, but in stock form your tractor would
have been equipped with a shut off valve/ sediment bowl (glass) below the fuel tank. That is
where the fuel line to the carb connects. That is where you would shut off the fuel each time after
use. This is one of the few times I would disagree with a response that Janicholson has made. I
think he did not consider or understand that the tractor was being used off and on while this issue
was being experienced. I feel that if indeed the gas did fill the intake tube from the air filter the
carb and the intake to the level that it would flow into a cylinder through an intake valve a couple
of problems would show up. First if the engine did start in this senerio you would immediately be
showered with raw fuel out of the muffler. Second and what I feel is most likely the engine would
hydro-lock because the fuel drawn into the cylinder cannot be compressed. I believe I'll go with
John....su on this one hydraulic fluid not gas is getting in your crankcase oil. The fuel pump
leaking is another option but you have not informed us if it has one. Not being totally familiar with
the C model if that is the case I believe your tractor would have to be equipped with a block from a
power unit(engine used to power something other than a tractor) Sorry for the long post and my
apologies to Jim N.
 
(quoted from post at 18:27:41 01/29/17) Maybe you posted this before you could finish your reply. Are you asking what the "bowl" is or
"sediment bowl" I'm sorry if I am stating something obvious, but in stock form your tractor would
have been equipped with a shut off valve/ sediment bowl (glass) below the fuel tank. That is
where the fuel line to the carb connects. That is where you would shut off the fuel each time after
use. This is one of the few times I would disagree with a response that Janicholson has made. I
think he did not consider or understand that the tractor was being used off and on while this issue
was being experienced. I feel that if indeed the gas did fill the intake tube from the air filter the
carb and the intake to the level that it would flow into a cylinder through an intake valve a couple
of problems would show up. First if the engine did start in this senerio you would immediately be
showered with raw fuel out of the muffler. Second and what I feel is most likely the engine would
hydro-lock because the fuel drawn into the cylinder cannot be compressed. I believe I'll go with
John....su on this one hydraulic fluid not gas is getting in your crankcase oil. The fuel pump
leaking is another option but you have not informed us if it has one. Not being totally familiar with
the C model if that is the case I believe your tractor would have to be equipped with a block from a
power unit(engine used to power something other than a tractor) Sorry for the long post and my
apologies to Jim N.
 
sounds like it could be fluid in the oil I have tried everything else mentioned. but it smells like gas and the oil comes out a milky tan color
 
It wouldn't run with that much gas going in it,. if it's parked on a floor there'd be gas all the floor from the carb. You got a leaky hyd. pump shaft seal.
 
It wouldn't run with that much gas going in it,. if it's parked on a floor there'd be gas all over the floor from the carb. You got a leaky hyd. pump shaft seal.
 
Milky tan oil is oil and combustion gasses. It could be a head gasket or a crack in a casting. Fuel in the oil does not
cause a color change. Jim
 
Okay, now we might be getting to the real issue. Milky, tan more describes what happens when coolant/antifreeze is getting in the oil. Are you loosing coolant out of the radiator? If the oil is milky in the crankcase now; let it set a day or so. Then crack the plug loose to where it will just drip. Does water or antifreeze drip out? If so you have found your issue. Don't run the tractor a lot with the oil/coolant mix in the crankcase it can be very hard on the bearings.
 
It has had recent overhaul I was told when I bought it. Could it be a ring was not installed correct when put in? Should I do a compression check to start with?
 
I had this same problem,with my 300 utility,I had a new AC C87 set in it and to this day still cant bring myself to ever use them again,had a bad new plug,putting around or loafing it'd run fine,put it under load, plugs would warm up and she would miss,by the time you made it to the shop to start investigating it would cool and run fine again.... should ad the SOB would purr again!!!! drove me nuts,it took me awhile to suspect the NEW set of AC plugs....
I know AC spark plugs are well regarded,but this hair pulling angony soured me of AC plugs forever...your not running champion D21's are you? I would try a set of Autolite 386's and if it fouls those try a Autolite 3116
 

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