Farmall 560 running rough

My 560 starts and runs great for about 5 minutes, Then it misses and runs very rough. I recently rebuilt the carb, not sure if its a fuel issue or a condenser or coil breaking down. Plugs points and condenser are fairly new.

If using a little choke when it begins, it is likely fuel delivery. Especially if it will not pull a load, or have enough power to use road gear (even with the
TA pulled back. If it just runs rough but is not affected by choke, and can pull OK, it might be points and condenser. Is the gap at .020 inch? Jim

What are you doing with the tractor when it does this?
Can you drive it around? Otherwise will the engine rev
up and keep going. If it is just sitting and idling you
may have a fuel delivery problem. Pull the carb drain
plug and after the initial dump of a couple cups in the
float bowl does it have a continuous steady stream or
does it slow to nearly nothing? There is a screen in the
fitting where the line attaches to the carb that can plug
check that, should have found that during the carb
cleaning. Should be a screen in the top of the sediment
bowl that stops the major crud from making it this far.
Did you possibly put an inline fuel filter in the gas line?
Some of those will not flow fuel on a gravity feed
system. If the fuel supply is good I would say try a
condenser from NAPA.

Edit: for a wording correction

This post was edited by used red MN on 04/08/2022 at 08:10 pm.

It is almost always the points. Start with the points.

Did you try opening the load needle 1/4 turn to see if it helps?

how was it before the carb job? also when missing have u pulled the choke out to see what it does? is everything set to factory spec's? point
setting, timing? carb settings? we need info. pretend we are stupid,... give everything you have done, or not done.

Put a vacuum gage on it . Tell us what you got .low idle fast idle

quite a few years ago a customer brought in a 560 to the shop i worked at.it was running poor i put in points condenser plugs and cleaned the carb.
this guy was a hobby farmer he bought gas in town so we knew it had fresh gas. i found pieces of plastic from the gas cans in top of the sediment bowl
where it screws into the tank. after cleaning it out it ran fine. we figured it would run fine with the gas in the carb. then it would be fuel
starved under load.

Several things to check and observe...

What does the exhaust do when it runs rough?

Black smoke is too rich, as in the carb flooding or the float set too high.

White smoke can be several things.

Coolant in a cylinder, sweet smelling water vapor, indications of a head
gasket, but would be accompanied by overheating and coolant loss.

Raw gas vapor, eye burning, strong gas smell, indication of loss of spark or
compression on one or more cylinders.

No smoke, just rough idle that clears up with higher RPM, can be carb out of
adjustment, minor vacuum leak, minor compression loss (check valve lash),
points adjustment, ignition timing, etc.

Based on these observations, you can make a better diagnosis.

Do check the points gap, check the distributor shaft for side play, try an old
condenser, check the electrical connections, especially from the coil to the
points.

If there is black smoke, revisit the carb, could be the float has a leak and
partially sunk, trash holding the needle valve open (a contaminated, rust
flaking tank will be an ongoing problem).

If no black smoke, try adjusting the idle mixture, turning the screw in
richens the mix, out leans. The idle speed must be down to 500 or less for the
mixture adjust to have any effect. If it still has no effect, the idle circuit
may be clogged.

Tight valves will get tighter as the engine warms. If they haven't been
adjusted lately, might give them a run.

Let us know!

Maybe plugged fuel cap.

Loosen it a half turn.

If you have an old one International/Farmall will send you a new one free. Part of an old liability settlement.

Check your oil bath air cleaner. Could be very dirty, not getting the air it needs. Seen this on several.

The tractor was always hard to start, but it ran real good. I rebuilt the carb now it starts very good and ran good for about a month. Now it starts and runs good for about 5 minutes then it breaks down and I can only keep it running with the choke out. Even with the choke out it runs very bad. I dumped the sediment bowl and drained a quart of fuel thinking I had water in the gas. Started again it ran good for 5 minutes then started running rough again.
It runs worse under load. I have no screen in the sediment bowl and I have a inline fuel filter that is fairly new.
When it runs bad I get no black smoke. It seems to be running on one or two cylinders, not much power. I am going to replace the inline filter tomorrow.
Thanks everyone for helping me.

Try a new condenser. When the condenser breaks down the spark gets weak and can't fire the fuel mixture needed to normally run the engine but it will light up a richer fuel mixture to a certain point. If pulling out the choke mid way helps it run a little better but pulling the choke out all the way kills it I would bet on the condenser being bad. If pulling the choke out all the way keeps it going you probably have a fuel starvation problem. A brand new condenser can be bad out of the box.

Replaced the fuel filter today, Seemed to run fine. I will keep you advised. I will keep you advised. Ran it for a short time.