9n will not throttle up

Did you check the advance weights when you had the distributor off?

First, check for fuel. Get a can & put it under the carb. Remove the bolt in the bottom of the carb; as long as the fuel is turned on, you should see gas flowing out of the carb. Let it run for at least 30 seconds. If it’s a dribble, or runs for 5 seconds & stops, or none at all, you have solved half the problem: it’s fuel related. If gas flows well out of the carb & only stops when you turn it off at the sediment bowl, chances are very good it’s not a fuel problem.

Next, try adjusting the carb.

Make sure the tractor is at operating temp; that usually takes 10 – 15 minutes at idle depending on ambient temp.

Both Ford and Marvel/Schebler (assuming you have a M/S carb ) say to set both the side-pointing idlemix and the down-pointing mainjet to 1-turn as a starting point. I set the down-pointing mainjet to 1-1/2 turns and don't fool w/ it until the final step.

Then adjust the side-pointing idlemix for fastest idle; not the smoothest idle. Next, adjust the behind the carb idle-speed set-screw for very slow 400-rpms idle. Do that idlemix adjust for maximum idle at least 3-times. Make sure that you turn the screws slowly, like 1/8 of a turn at a time & wait a second or two for the engine to catch up. Take your time!

Do it like this:

1. Adjust idle mix jet until RPM increases

2. Adjust idle-mix set screw until the engine nearly stops (as slow as you can get it unless you have a tach that tells you 400 rpm)

Repeat steps 1 - 3 three times.

Remember the side-pointing idlemix is out for lean, in for rich.

If you do not have any problems inside the carb, it is easy to get the idle down to 350 - 400 rpms.

Your last step is to go back to the main jet. Remember, in for lean, out for rich. If you end up turning it OUT more than ½ turn for max power (remember, you already had it 1 ½ turns out) then stop right there because you have a dirty carb or a fuel problem.

Lastly, each of us has his own definition of a carb rebuild. If your rebuild did not include soaking the carb 24 hrs in a bucket of caustic carb cleaner & blowing out every orifice w/ a rubber tipped air gun, you didn't do a rebuild, IMHO. You just replaced parts.

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You replied " The cap, rotor, plugs are all new."

So what about the points & condenser & the timing? Did you replace them, & set the timing?

" What weights on the distributor? "

The advance weights.

A new cap & rotor & plugs don't get you much w/o new points at the correct gap and having the timing set.

And none of that will fix sticky or broken advance weights.

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