New to this: '47 Farmall A throttle issue

[Petermac7644]

Hello,

I acquired a '47 A a year ago. Love it. I hilled potatoes with it all summer. Now I've got an plow blade on it. It'll push a good amount of snow.

The tractor starts easy and Idles. I can't seem to run it at half throttle. I idle it for a bit after startup and then move the throttle quickly to wide open. It will run that way. Moving the throttle anywhere in-between kills the motor most of the time. I've been able to slowly move it up to about 1/3rd throttle. Behaves the same after it's been snow plowing for an hour.

I have a new reproduction marvel shebler style carb on it. It was Zenith originally but I couldn't get the jets out to clean them. Rebuilding that carb is on my to-do list. The one I bought looks like the distillate option with the main jet adjustment.

I've fiddled with the screws probably more than I should. It was idling rough and I adjusted what I thought was the idle screw but now looking at the manual I think it was the main jet.

Just looking for some advice on what to troubleshoot.

Since I've owned it I put the new carb on and replaced fluids and spark plugs. I'm not the entire way through the 'what to do when I first get tractor' list but I'm getting there. I get about a half turn out of the steering wheel before the worm gear engages and the manifold is pretty rough looking... I'm having fun wrenching on it.


Here's a pic from installing the plow

[Don McCombs]

Lubricate all of the pivot points in the throttle linkage system, including any on the governor. Work the linkage back and forth until it moves smoothly. Check for any place where it may be bent or binding.

[inairam]

I agree with Don. It sounds as if the governor is not responding. Get the linkage all moving fee and smooth like he said. I would also adjust the linkage between the carb and the governor per the manual - especially since you have replaced the carb.

If it starts, idles, and will run at full throttle it does not sound like the carb.

[Petermac7644]

I hit the governor with PB blaster on Wednesday. Plowed snow Friday and it worked a lot better. Today I took a stab at adjusting the connecting rod to the carb. I don’t have enough adjustment on the connecting rod yoke to synchronize them but I got it as close as I could. We’ll see if that makes a difference - more snow on the way Tuesday. Many thanks for the advice.

Peter

[RRicks1970]

My Super A I bought had the touchiest throttle. I had to slowly accelerate or decelerate to keep it from wanting to die. Turns out somewhere in its 70 years of farming someone pulled the weights out of the distributor. I installed an updated distributor and now it responds like a champ. Just gotta do some filing on those throttle plate notches to keep the arm from slipping.

[Petermac7644]

We got about 6 inches of heavy wet snow. Went out today after having adjusted the connecting rod. I'm only getting about half throttle when I push the throttle lever to wide open. I can pull back on the connecting rod by hand and get it to rev up but then the governor pulls it back on me. With the engine off and the the throttle lever pushed forward, the connecting rod moves all the way back. Any tips on how to adjust it so I get more RPMs at full throttle?

Another issue I had today was the tractor surging under load. I put it away and finished up with the ATV.

[Don McCombs]

Lube ALL the throttle linkage pivot points, again. From the throttle lever to the governor. Recheck the governor to carb rod adjustment, again. If you don’t have enough adjustment in the existing rod, replace it.

[SamsFarm]

I'm only getting about half throttle when I push the throttle lever to wide open. I can pull back on the connecting rod by hand and get it to rev up but then the governor pulls it back on me. With the engine off and the the throttle lever pushed forward, the connecting rod moves all the way back. Any tips on how to adjust it so I get more RPMs at full throttle?

How do you know your not running at rated rpm?

Did you hook some sort of tachometer up?

Those ole engines were slow runners!
Rated engine rpm's is listed at 1400.

http://www.tractordata.com/farm-tractors/000/2/8/285-farmall-a-engine.html

The serial number tag under the seat has the max rpm listed.

Seems as if I remember right my super A is 1815 rated rpm

[Petermac7644]

Hi - no I haven't measured RPMs. I'm just basing it on videos I've seen of other A's and going by the sound of the engine and tractor speed. It's entirely possible that I'm wrong about it being too slow. Ground speed could be due to tire size mine are 8.3x24.