Ballpark carb setting for an A

Farmallb

Well-known Member
Which way do I turn the jets to start. Clockwise, or Counter clockwise? how many notches do I adjust them to. Inside and outside. Thanks.
Ive got a 39 A. Ive had the carb gone through twice with one new kit put in it.
 
Fly wheel side, 1/4 ta 2 turns counter clock wise after being screwed clock wise to shut off. Clutch side 3/4 to a full turn counter clock wise.Final adjust after 180 degrees warm up, running.
 
Turn the jets clockwise to close them, not too tightly, then open each one about a turn and a half for starting and after the engine starts let it warm up for 5 or 10 minutes then adjust the idle jet (the left one, flywheel side) with engine throttle closed to where the engine is running at a slow speed and adjust the idle needle to where the engine runs most smoothly then open the throttle up to wide open and adjust the power jet needle closed until the engine starts missing then open it about a half a turn. Then run the tractor in road gear around a little make it work and then fine adjust the power jet. Ideally it should just put out a tiny wisp of black smoke when it is pulling hard, never miss and accelerate smoothly when you open the throttle. You've gotta have a good ignition system (plugs, points, and wires), a clean air cleaner, and good fuel running freely into the carburetor and the engine warmed up to get the best tuning adjustments.
 
On my A if I adjust the idle jet for the smoothest low idle it runs pretty fat when motoring along in road gear so I tune it to run its best at high idle. I hook it up to a pto driven orchard sprayer to set the load needle. It's about 1 1/4 turns out.
 
Well, I tried the settings as suggested. Not a snap crackle or fart. lol Both people working on it said they thought IO needed a new carb, and so I guess I do.
 
Idle needle about 1 1/2 to 2 turns open, load needle around 3/4 to 1 full turn open. Once these are set there is no reason to change them unless the fuel changes. If a tractor is in proper tune it doesn't need the needles changed on start up. Mike
 
farmallb,
Put a couple of squirts of gas in each spark plug hole and crank her over. She should at least run a few revolutions if it has spark and timed right. If it does you have a fuel problem. If it doesn't you have a spark, compression, or timing issues. Jet settings won't stop it from at least trying to start. Let us know how you make out and we'll go from there. good Luck!
John
 
Ill do it tomorrow, and thanks. I havnt got the gas line hooked up, I just was pouring gas into the 2in dia cap on top the carb. I have it running by hammermill belt off of my 48 H Farmall. I wonder if that has anything to do with it lol.
 

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