Mag and Carb questions on '35 A

The second problem I haven�t solved. It runs great now when there�s no load but starts shooting out black smoke and running really rich under a load. It�s not like a freight train or anything but enough to tell that�s something�s definitely not right. I adjusted the idle setting and I feel it is ok, but the load setting doesn�t seem to affect it much at all. I�m wondering if the problem I had with the magneto may be part of the problem.

Any help would be appreciated!

Joe Lee

First you ask about the use of an extra gasket behind the mag and I have seen that done before and work in instances where theres wear and/or thigns are binding up where the governors female drive cog mates to the mag. If it works now dont fix or worry about it in my opinion.

That runnign rich if its excessive can eventually foul the plugs. The idle adjustment needle affects the idle but not the power and load conditions and I doubt its a mag problem assuming Robert Beaver rebuilt it.

The first thign I would do is adjust the load needle to approximately 3/4 to 1 turn out and load her down the best you can (on PTO or belt pulley if you have a load) and lean it some but not to where she starves for fuel under a good load and see how she performs.

If she still tends to run too rich and blows out excess black smoke and a needle leaner adjustign dont help or make much difference, I would remove the air intake and make sure the choke butterfly is tight on its shaft and is staying open where you set it.

If all that still checks okay you may want to remove the air cleaners lower oil reservoir bowl and check it and the mesh cleaner for any restrictions since an air inlet restriction can makes them run over rich and possibly throw black smoke.

If theres no air restrictions and settign the needle leaner in dont help much, I question the float level setting but Robert surely got it set right????? and the needle and seat are probably okay unless a speck of dirt got lodged in there.

Is the start timing about right and she start good and doesnt kick the flywheel backwards?? Still regardless where its (start timing) set at I wonder if the run advance timing is okay, it should be around 25 BTDC at RPM. At medium to fast RPM does she pop very loud even if no load????? ? Such can be indicitave of too slow run timing. Rotating the mag just adjusts the initial start timing, the run time advance is dependant on the setting at the rear of the mags coupler and Robert likely set it around 25 if he worked on that part of it.

Check the easy simple things first, try a fresh set of Autolite 3077 the hotter side wire electrode plugs, lean the power needle in a tad, check the choke butterfly plate and any air inlet restrictions, and see how the old girl does.

Post back or e mail [email protected] with any more questions. Is the engine and compression etc in good shape?????

Good Luck n God Bless

John T in Indiana

~On your black smoke?...try setting the load needle to about 1 turn out from seated to start with then slowly turn it in 1/8 turn more at a time the road test it under load. You really can't set the load needle without a load on the tractor as it won't open the carb throttle plate enough just sitting still [even at wide open throttle]...The idle needle should have very little effect on the load part of your carb metering..

~I would suspect that maybe you have a plugged air cleaner inner element [common problem on the old used Deere's]. You really can't see in there & it doesn't come apart easily.....Try running it with the air cleaner intake pipe disconnected to see if the black smoke goes away, if so you will have to pull the air cleaner & drill out the spot welds then clean the inner element of all the old crud & caked in dirt...

~If the black smoke only shows up on throttle up then goes away after a few seconds that is normal & is just the enrichment well supplying fuel on throttle position change [kind of an early from of accelerator pump system].

~You could possibly have a carb problem or high float level but eliminate the above first...

~Post back or E-Mail with any questions....

[email protected]