[AT] My Stupid JD A again

[jtchall at nc.rr.com]

Tyler, I'm in agreement with the rest, stay off the road until it is fixed. 
Even running down the road in high gear will not do very much to remove 
carbon deposits. Putting it under a load and drying it out is still not 
going to correct the problem.
I'm still contemplating why the plugs are fouling. Right now I would say it 
is a possible combination of things. Seeing how the the tractor is hand 
start (I think) there is probably no problem with the magneto. If it were 
you'd be having a terrible time cranking it. I would make certain the wires 
and plugs were in good condition.

My next guess would be carb issues--either out of adjustment or just plain 
worn out. That coupled with a manifold leak, assuming it is on the intake, 
is going to make things run horrible. Look for a lot of wear on the carb 
shafts to see if they are sucking air. Also, you may for a temporary fix be 
able to seal the intake manifold by running a bead of silicone around the 
outside. It wouldn't be pretty nor a permanent repair, but for less than $10 
you could rule out an intake leak assuming you could run a bead around the 
entire intake.

As for the difference in sound you are hearing with the petcock open, have 
you got someone who would come do a compression test or loan you the tool as 
was suggested earlier? That's about a 10 minute test that will tell you a 
lot. If both sides read high, your piston rings and valves are in good 
shape. If both are low, your engine is worn out. If you have mixed results, 
you either have one side with stuck or broken rings, bent or sticking valve 
stem, a leaking head gasket, or a crack somewhere in the combustion chamber 
(not likely but possible). The only problem I see with this test is if your 
tractor uses BIG spark plugs, like W-14 Champions or pipe thread, You may 
have to rig up an adaptor to fit the tester. Some of the Deere collectors on 
this list should know what plugs yours uses.

Keep us posted, glad to see someone actually working on an antique tractor!

John Hall