carburetor 440ic

[crgenther]

I have a Marvel - Schebler TSX carb on my 440ic. It seems that when I let the tractor set for long periods the needle valve quit working and gas floods out of the carb when I open the valve on the sediment bowl.
This time I replaced the float needle valve and seat on the gas still pours out of the carburetor. I have cleaned all the parts checked the float adjustment and reassembled it carefully several times. when the carburetor is dry I can turn it upside down and can't blow through the gas supply fitting. I can here the float moving when I turn it over, so I think that is free. The float has no fluid inside it when I take it apart and no visible holes.
that could drain as fast as I take it apart. This is such a simple system I can't figure out what else could go wrong. Any help would be appreciated.

Curt Genther
In Bow, Wa

[DukeofDeere]

Attach just the top of the carb and close the float by hand to see where the fuel is coming from..
Check too if the float can drag on the inside of the carb..

Duke

[Wall:E]

Mine developed the identical issue after sitting for two years but I've been running the motor dry after I close the valve. I'd love to share my experiences in repairing the problem but I haven't initiated that process yet. Let me know what you find, though, and good luck!

[Tigerhaze]

Check too if the float can drag on the inside of the carb..

Duke

That is something I have noticed before on my M-S carbs; it would be worth checking as it sounds like everything else logical has been checked.

[Paul Buhler]

Check that you have the correct float for your model. As stated, it may be hanging up preventing the needle from seating fully. Good luck.

Check this manual. Hope it helps. Paul

http://l-36.com/carb.pdf

[DukeofDeere]

Could be a bad float too.
Take it out and shake it to see if there is fuel in one side of the float or the other.

Duke

[crgenther]

Thanks for all the help. I took the carb a part after sitting with the bowl full of fuel, and the float had fuel in it.
After installing a new float from Roberts Carb Repair for $30, I am back in business.

[DukeofDeere]

Glad you are back up and runing.

Duke

[crgenther]

Thanks Duke,
I am running, however, I am over heating after about 50 minutes of operation (the bulldozer is too:).
I installed a new thermostat and new cap on the radiator, but sill getting hot.
I guess that leaves the water pump or the radiator.
I don't even know where to get radiator work done around here any more .
All the shop I used to know about are out of business. Too many regulations I think.

Curt

[DukeofDeere]

Could always flush the radiator. Check too if the external openings are clean. Look inside the radiator too see if the tubes are calsifying or pluged up.
Where are you located? Which state? There are a few shops here in West Mi.

Duke

[Lavoy]

Make sure to get an estimate first if you have to have it recored. New radiator might be less than a recore job.
Stupid question, but you didn't get the thermostat in backwards?
Lavoy

[Ray III]

Need a new float too, apparently even brass starts to age after half a century. Nearly set my machine on fire when it first started leaking! Have to shut the fuel off and let it run dry when I park it.

For the overheating issue, first I'd make sure it was full of coolant (yes really, with the engine off the top of the radiator core should be underwater). Then check tightness of water pump belt.

After that, start the engine with the cap off and watch in there. Upon the thermostat opening, you should see a good amount of flow happening (be ready to put the cap on quick if it tries to come out). With the low horsepower of these engines, you may have to work it to get it to t-stat temp then VERY CAREFULLY remove the cap with engine off and a rag over the cap, turn to first click to release pressure first. Then start again and look. If flow is poor, your water pump impeller may have deteriorated or the radiator may be plugged.

[crgenther]

I triple checked the direction of the the Thermostat before I bolted it together, so I am sure that it is in the right, however, I see that the manual calls out for 160 degree for gasoline engines and I installed a 180 degree. I wonder if this could be a problem?

[DukeofDeere]

20deg can make quite a bit of difference.
My 420 heats up to normal temp without working her at all. Under hard load only climbs a few deg. 440 needs to be worked to warm her up.
Is get the 160 stat for her if it were mine.

Duke

[jtrichard]

when you have the stat out you might want to do a simple test on the rad. take the lower hose off hold your hand over the outlet...fill the rad when full take your hand off and it should empty almost instantly if not its is getting plugged .. you can also put a garden hose in the top and see if it will take all the flow (has to be good flowing hose not a trickle)