Farmall cub will not run

My cub was running fine then just quit like it was out of gas... I changed the plugs, plug wires, cleaned and rebuilt the card, new gas line and bowl, new points.. the timing seems to be set.. I finally got it started but it starts at a very low rpm and will gradually speed up and run... when I engage the mower or put it it in any other gear but 1st it dies..I am at a loss on where to go from here... am I dealing with a governor issue? Thanks for any answers I get

Welcome to YT, Jeffrob.

Not really familiar with the Cub though have a couple other Farmalls in the shed.

It sounds like it's starving for fuel, and from the carb, not the tank. If it started well and then choked out with load after running a minute or so, it could be a bit of flotsom in the tank covering the fuel outlet and restricting (or stopping) flow, but when given a rest, the fuel flow catches up and refills the float bowl. This sounds like something not right in the carb, like something plugging up an orifice, or an air leak.

Did you replace the gasket to the manifold? Have you checked the throttle and choke plate screws to make sure they are tight? Is the throttle plate shaft loose where it pivots in the carb housing? If so, it could be pulling air and running really lean. In some carbs there is an O-ring around the throttle plate shaft to help seal it. Could be the O-ring is now shot, or after cleaning the varnish out of the carb, there is more space around the shaft to pull air.

Also, you might check the distributor shaft for wiggle. If the bushings are excessively worn, the point gap may seem set right, but when running may be 'all over the map' because the shaft is floating.

Hope that helps. Let us know what you find.

Well to start with ALWAYS trouble shoot before parts or you are likely to ad to the problem.
#1 check to make sure you have a good blue white spark that will jump a 1/4 inch gap or more at all the plugs wire and if it has a coil at the coil wire.
#2 check that you have a good gas flow at the carb drain plug. It should fil la pint jar in under 3 minutes.
#3 when was the last time you checked the air cleaner and dumped the mud and water out and put in new oil.

Does choking it hurt or help?? Post back what you find for more help

Did you check the screen in the elbow where it enters the carb?
Or - check the air breather for obstructions?

Op had it right-govenor issue