Farmall super M dies after 20 minutes

I have a Farmall super M that dies after 20 mins of running. Tractor will idle fine then 20 mins later starts chugging and dies. Will not start for another 30-45 min.
Just replaced coil, condenser, and point with no change.
No junk in the tank, bulb fuel is clean, filter is clean, ran 1 gal of gas from line with no debris noted.

Do you have a 12 volt conversion with a resistor? If so maybe the resistor is over heating and causing your problem.

Loosen gas cap when it dies. See if it will restart. If so, fuel cap is not venting to let air in as fuel is used.

Filter? There's your problem. They shouldn't have one. It's vapor locking when it gets hot.

I agree about the filter. I put one an Allis Chalmers I have and it did the same thing.

Once it stops , thats the time to start looking for the problem. Check the spark at dist by pulling out the wire a bit And have someone one crank it over. Should be blue and hear it snapping. Remove line from carb and make sure u have a full line flow of fuel as u might have the sediment bowel inlet with junk in it. How long did it take to run that one gallon of gas ? Did u remove carb drain and catch the fuel in a clean can to see if any junk or water ? Then inline filters cause more trouble than they prevent. They are made for a fuel pump to push fuel through them. Is there gas in it when it stops ? This is a few things to check then report back.

Hello Moe welcome to YT! Everything I will add would be covered by what rustred suggests but just want to highlight a couple things. The main thing, he is telling you is to check the fuel flow from the carb drain. The fuel has to get inside of the carb for it to get in the fuel circuits to run the engine. Not sure how much you been around Farmalls, if you have been you would know about this. The fitting that screws in the carb that the fuel line connects to has a fine screen on it, see the link. If you did not know about it you need to pull it out and clean it. However It is fairly rare for that stopped up carb strainer fitting to keep it from restarting for 30 to 45 minutes. Although with just the right amount of fine lint etc. there is a possibility it could seal up fairly tight. It is possible a new condenser can be bad also a new coil, for them to act exactly the same is rare. Not sure what your wiring is like but there is a possibility that something is loosing connection there as well, maybe the internal switch contacts. If you get to the point where it has stalled and will not restart run a lead direct to the coil or switch side of the resistor from the battery post. If that keeps it running continuously then the problem is in your wiring somewhere. Also once a resistor, or at least the original ceramic block style, has failed they are failed for good. It has a coiled wire in it to build the resistance. The wire runs hot due to this. When it fails and breaks apart, the wire ends then pull away from each other when the coil cools leaving no possible way for them to reconnect. There may be other types of resistors that may possibly reconnect after failure. Good luck! Let us know what you find.
YT IH carb inlet fitting

What rustred said about the fuel inlet to sediment bowl, would be my first guess/place to look. Above the shut off valve, there is a pipe spout that goes up into the tank. Debree will get in that pipe, and restrict flow. How long the tractor runs, depends on how restricted the flow is into the sediment bowl. But won't start for 30 to 45 minutes after it dies, sounds like a little long. If it ran for 20, it should start back up in 5 to 10. Are you sure it wouldn't start for 30 plus minutes?? Or did you just wait that long to try?

Otherwise, my next guess would be electrical. Perhaps something you replaced was bad out of the box? OR, maybe you replaced 12 volt stuff with 6v stuff, or vise versa. Your new distributor parts, must match what voltage your battery is. If you just walk into a parts store, and tell them to look it up, they'll likely give you 6v stuff (not knowing that it has had a 12v conversion).

Thanks everyone for the input. We will work a few things tomorrow and keep you posted.
To reply to a few of you. The tractor is set to a 12v system, coil, condenser, and points were purchased from Steiner and labeled for 12v system.
We have also noticed that the tractor has a lack of power under load. I assume this has some correlation, I forgot to post this originally.

I chased one of these 20 min. shutoffs for about a year. Turned out the wire to the coil from the key sw was broken except for a few strands. As they heated the resistance increased till it would stall. Pulling out the choke would make it run better near the end of the cycle. A multi meter hooked to the coil while running was the key to the fix. I have been told that corroded switch will cause the same issue. HTH

no that is not the main thing i am telling him, my concern is to make sure you have full fuel flow to the carb as i always want to know on my own units and others. no idea why people are worried about what comes out of the carb. that is not an accurate test. u do that test after u know u have full fuel flow first. i explained just as it should be done. you can have fuel tricking into the carb and trickling out the carb drain dont mean u have full fuel flow, without first checking the main flow. i said to remove the carb drain to check for water or junk in the carb bowl and do the fuel check there at the same time. thank you.

you can put all the new parts on any engine you want,... if the tune up is not done then u wasted parts and time. did you check compression? did you set plugs to .025,.. the points to .020, them set the timing??? then set the carburator, main jet on bottom to 3 turns out, mixture screw 3/4 turn out, then set the idle to 400 rpm. she will run like a champ. and for the record... a major tune up includes a valve adjustment also which is .017 warm. when i get done with these engines they idle so quietly and smooth and start with a touch of the starter,... there is no cranking and cranking. half a flip and they are running. more info and work for you, plus dont know what u know on tune ups and u ask i will tell , but i dont waste my time typing books here.my thing is if you are asking and working on the tractor u must have some knowledge behind you. these settings must be done in the order i said.

Rustred, my wording got off a bit there. Sorry, I did not mean to change what you said, it certainly came out that way. I like to acknowledge when others have posted an idea or approach to the problem that I am going to build off of or place my clarification on. In this case I should have made it more clear that my methodology was a bit different but based on the same end outcome. I guess I should just use your direct approach and tell him his blaadity bla tractor will never run right if the carb fuel inlet strainer screen is plugged.

(quoted from post at 13:02:14 07/11/23) Loosen gas cap when it dies. See if it will restart. If so, fuel cap is not venting to let air in as fuel is used.

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I recently had this problem with my Super M.