4 Star Stumbling

J.A.R · Mar 15, 2019

Went to start my tractor this morning been sitting about a week fired right up but was missing alittle. Let it run till it warmed up and the miss went away. However after moving some snow alittle later I noticed when I let the clutch out it would stumble every time but then run strong after the clutch was completely engaged. Dont know if I should be looking at the carb or hopefully not the governor. Carb is rebuilt and all electronics are new. Tractor worked great the last snowfall.

T.R.K. · Mar 15, 2019

I know Dad's ZB wants more fuel in the Winter. I would try turning in the idle screw 1/4 turn. Turn the main screw out 1/4 turn. You can
always go back to your original setting if it doesn't work.

The reason you turn the idle screw in is its an air bleed. It meters the amount of air in the idle circuit, not the fuel. So to make fuel
mix richer, you restrict part of the air by turning the screw in. At least I think the carburetor on a 4star works the same way.

J.A.R · Mar 15, 2019

I will give that a try then. Just kinda wondered about that cuz iv never had to adjust the carb on my U but I'm open to any an all opinions thanks again.

MMDEL · Mar 16, 2019

Did you pull out the choke just a tad and see if that makes any difference. That would indicate it might be a little on the lean side especially in cold weather. If so then turning the load needle out a little. But I wouldn't mess with the idle adjustment unless it is not idling like it should.
MMDEL

4 Star Stumbling

J.A.R

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T.R.K.

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J.A.R

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MMDEL

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