Farmall Cub

Hello Everyone,

I am trying to figure out where to begin with this problem I've been having. No matter how lightly I let off of the clutch the tractor automatically gets bogged down and dies (unless I quickly push in the clutch in which case the motor revs back up to idle). Any suggestions of where to begin?

Transmission might be engaging more than one gear. Does the engine start with the transmission in neutral, clutch not depressed? Can you roll the tractor with the transmission in neutral, engine running or not running?

Sounds like it is not running right, does the cub roll in neutral? We might need a little more information. New to you, had it a while? Might be a plugged main jet. Just guessing until you can elaborate on it.

Lnk wrote:Sounds like it is not running right, does the cub roll in neutral? We might need a little more information. New to you, had it a while? Might be a plugged main jet. Just guessing until you can elaborate on it.

The tractor is running. It's new to me. It is a 1952 Cub. I was hilling some sweet corn when this started. I recently cleaned the carburetor, but that was my first time ever working on a carburetor. I know it needs a new fuel line. Not sure if I just did not do a good job with the carburetor cleaning, or if the fuel line could be the problem.

It does roll in neutral. I didn't have a chance to start it today so I'm not sure if it will start without the clutch pressed in.

-Kaleb

Does the engine run at different speeds as you advance the throttle? Does adding choke have any affect on the engine stalling out problem? Easy check is to remove the hex nut on the side of the carb, turn the fuel on and allow a flow for a couple minutes, catching it in a clean container. Flow should not slow down but full stream. Also this would be a good time to check the main jet for any obstruction and clean as needed with a fine copper wire and carb cleaner. The jet orifice is only about .032 diameter so it don't take much to restrict the fuel flow. Good Luck.

if it rolls in neutral transmission/brakes are not the issue

staninlowerAL wrote:Does the engine run at different speeds as you advance the throttle? Does adding choke have any affect on the engine stalling out problem? Easy check is to remove the hex nut on the side of the carb, turn the fuel on and allow a flow for a couple minutes, catching it in a clean container. Flow should not slow down but full stream. Also this would be a good time to check the main jet for any obstruction and clean as needed with a fine copper wire and carb cleaner. The jet orifice is only about .032 diameter so it don't take much to restrict the fuel flow. Good Luck.

When I advance the throttle it often takes a while for it to throttle up. I think that's a linkage problem thought because I can get the engine to rev when just pulling the thottle on the carb. I will check and see if the choke has any effect. The fuel does run continuously when taking the fuel line out of the carb. I am hoping its the jet, but worried it could be something wrong with the govenor.

Lube all the throttle linkage especially the lever on the governor where the long rod attaches. Typically does not move freely due to not getting lubricated . It's #11 in the picture. The long rod has a clamp on top of the engine head (not in the picture).

make sure the governor rod to carb is adjusted correctly

staninlowerAL wrote:Lube all the throttle linkage especially the lever on the governor where the long rod attaches. Typically does not move freely due to not getting lubricated . It's #11 in the picture. The long rod has a clamp on top of the engine head (not in the picture). gov throttle shaft.JPG

Thank yall! I will lubricate the govenor linkages. I definitely have not done that yet.

Take your time on the lever, they can break. Spray and gently tap until it loosens and moves if it's stuck. If the spring looks to be in bad shape, a new one may be needed.

Kalebtrojacek wrote:

staninlowerAL wrote:Does the engine run at different speeds as you advance the throttle? Does adding choke have any affect on the engine stalling out problem? Easy check is to remove the hex nut on the side of the carb, turn the fuel on and allow a flow for a couple minutes, catching it in a clean container. Flow should not slow down but full stream. Also this would be a good time to check the main jet for any obstruction and clean as needed with a fine copper wire and carb cleaner. The jet orifice is only about .032 diameter so it don't take much to restrict the fuel flow. Good Luck.

When I advance the throttle it often takes a while for it to throttle up. I think that's a linkage problem thought because I can get the engine to rev when just pulling the thottle on the carb. I will check and see if the choke has any effect. The fuel does run continuously when taking the fuel line out of the carb. I am hoping its the jet, but worried it could be something wrong with the govenor.

You need to check flow into the carb, pull the plug off the bottom of the carb to check flow. Your needle may not be allowing enough flow.

Lnk wrote:

Kalebtrojacek wrote:

staninlowerAL wrote:Does the engine run at different speeds as you advance the throttle? Does adding choke have any affect on the engine stalling out problem? Easy check is to remove the hex nut on the side of the carb, turn the fuel on and allow a flow for a couple minutes, catching it in a clean container. Flow should not slow down but full stream. Also this would be a good time to check the main jet for any obstruction and clean as needed with a fine copper wire and carb cleaner. The jet orifice is only about .032 diameter so it don't take much to restrict the fuel flow. Good Luck.

When I advance the throttle it often takes a while for it to throttle up. I think that's a linkage problem thought because I can get the engine to rev when just pulling the thottle on the carb. I will check and see if the choke has any effect. The fuel does run continuously when taking the fuel line out of the carb. I am hoping its the jet, but worried it could be something wrong with the govenor.

You need to check flow into the carb, pull the plug off the bottom of the carb to check flow. Your needle may not be allowing enough flow.

When i pull the plug in the carburetor I have a continual streem.

When you get all the throttle linkage and connections free, lubed and moving correctly, check the connections on the rod that crosses behind the radiator and connects to the rod from the carb. Wear or loose connections can cause the governor to not respond properly. There is a keyed connection on the end next to the governor. Search this forum and check the HOW TO Subforum for different ways to take out the slop caused by wear.

Im just getting back to this project now that the temps have cooled off. The tractor won't start now. I am going to rebuild the carburetor and clean out the main jet like y'all suggested. I also noticed that the dust cover in the distributor has a piece missing. Ive never replaced the distributor cap and might need to do that when replacing the dust cover. How do I go about checking to make sure that the spark plugs are getting spark?