3010 gasser

[bobmiller]

seems to be running rough and smoking black at idle. Pulled the plug wires while running, the two middle cylinders does not effect the running.The first and fourth cylinders make it almost quit. I checked the compression at cranking speed and all cylinders vary between 152 and 156 lbs and factory spec says 160.When I pull the wires there is good spark out of the cap. Could the wires be bad but that seems to simple. Thanks Bob

 

[Anonymous-0]

Wires could be bad. They were when I bought my 4020. Copper wires are a must, carbon wires are no good.

Champion plugs don't tolerate much abuse and don't clean up well. AC or Autolite do better.

The float needle valve is worn and leaking. Replace needle and seat and while you are in there, check the float for leaks. If its a MS (diecast) carburetor, the diaphragm may be split, tuning the MS carb is difficult.

The choke may not be opening all the way.

Birds and bugs may have nested in the air pipes from the precleaner to the carburetor. That will make it smoke black.

The precleaner top may be domed down instead of up, choking the intake air.

In cold weather it needs carburetor heat. My 4020 wants heat up to 90 unless plowing then only up to 70.

Timing is critical, needs to be about 20 degrees advanced at 2000 rpm.

The factory added a fuel shut off solenoid to many new generator tractor carburetors. It moved the needle in the min jet. When it goes bad, some have cut it off, then the main jet runs rich. And running rich is what makes the black smoke.

I had to do all these things to my 4020, cut the annual fuel consumption from 400 gallons to 250 doing the same work and eliminated that black cloud.

Gerald J.

 

[Bob]

Is it possible you have the wires to the middle cylinders (2 and 3) swapped?