Farmall H Carb tuning after rebuild

So I’ve finally gotten my H put back together enough to move around. She starts like a champ and will idle up fine, took it for a short ride around the yard and on the flat it runs good, but I noticed on an incline it starts to kinda choke out and hesitate a bit. I’d assume this would be carb related? This is after a complete overhaul of the engine and head, haven’t tuned the carb since long before this overhaul when I rebuilt the carb about 3 years ago. TIA for any help.
 
that is just not right! an engine rebuild and not the carb. plus did not even adjust it, get her soaking in the gunk.
 
By "choke out" do you mean black smoke? It may very well be that the carb just needs to be tuned to match the new engine. But it is also possible that something got in there while it was off the tractor and plugged something. This is also assuming the governor is adjusted properly. What kind of ignition? Is the gas fresh? Please provide more information.
 
Try turning the high speed mixture screw out 1/4 turn and see if that helps. Could be it's just running a tad lean. If that doesn't help, you can always put it back where it was. Nothing lost.
 
(quoted from post at 06:02:06 09/14/20) Try turning the high speed mixture screw out 1/4 turn and see if that helps. Could be it's just running a tad lean. If that doesn't help, you can always put it back where it was. Nothing lost.

The factory initial setting on the high speed idle is 3 turns out. That is where I have set ALL of mine, and never needed to touch it again.
 
I don’t think that a carb rebuild is required for an overhaul. Sometimes you can mess up more stuff by opening it up then if you just leave well enough alone. Just my opinion.
 
You think it just needs adjusted to the fresh engine? We rebuilt the carb a couple years ago and it hasn’t given us any issues prior to this overhaul.
 
First off, there is no such thing as a standard setting on those carburetors. Initial settings are suggested to just get it up and running before you can make a better more accurate adjustment although it may work fine on factory initial adjustment.

You might want to turn the main jet adjustment in all the way until it bottoms while counting the turns just for the record. Then back it out to where you originally had it.

Then start engine and allow it to warm up at moderate speed for a while. Now, pull throttle to full rpms which should be right close to 1800 rpm's. Turn main jet needle in until engine slows or starts to stumble. Then turn it out until it runs smooth and give it another half turn out.

If it smokes black after doing that, you have carburetor problems. Dirty, oversized main jet, fluel level too high etc.

Now adjust low idle speed and air mixture. The air mix should adjust up from half turn out to maybe two turns. If not, carb problems.

If it still stumbles under load, you make sure you have full fuel flow out the bottom drain plug on carburetor. Let it drain for a minute or so to make sure good supply continues.

Don't over look ign timing. Top dead center static timing (meaning engine not running) and then check advance of spark when running at full throttle. . Should be 40 degrees factory battery ignition, 30 degrees with flat head over size (3 7/16) pistons is best but 40 works ok for most, or 22 degrees with fire crater style dome piston all considering gasoline head.

If magneto, impulse snaps just a degree or two up to five degrees after top dead center and close to 35 degree advance of spark at all engine speeds
 
well its kina a standard procedure ,as you dont want a flooding carburator on a fresh overhaul washing the cy's down.
 
Could also be missing if something is loose on the ignition side, or timed wrong. You might not notice the problem until you were on the slope and the engine loaded a bit. If it bucks that seems more like ignition than starving for gas, but I'm not there to see it. Does it slow down and then come right back up on its own? Or does it just slowly lose RPM when under load, like it is trying to pull too heavy a load? The first is more likely ignition; the second is more likely carburetor. But even something as simple as a sticky float could cause the first. What kind of ignition?
 

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