1973 JD 1520 acts fuel-starved after 1 hr operation

[jamhouse]

new JD owner. I have a 1973 JD 1520 that acts fuel-starved after an hour or so of operation. once it cools some it will start and drive for only a few minutes if that. After sitting for several hours or overnight it runs great for about an hour then the symptoms come back. I replaced the fuel shut-off solenoid because the one on it was leaking at the wire and the insulation was worn through. The tank was drained and inspected with no issues found. No problem found with carb. There does not appear to be a fuel filter anywhere on the line. The tractor is not overheating. I have also tried loosening the fuel cap with no change.

 

[Tx Jim]

Welcome to this forum
Check to be sure fuel tank is venting.

 

[jamhouse]

Thank you Tx Jim Looking forward to learning about this machine. Never had one.
I've loosened the cap with no change. original cap so does not seal well anyway. can the fuel pump be going?
I had an old 1940 Chevy PU that had a similar issue but was a coil that would get hot and once it cooled it was good for a few hrs of driving.

 

[cjunrau]

I've loosened the cap with no change. original cap so does not seal well anyway. can the fuel pump be going?
I had an old 1940 Chevy PU that had a similar issue but was a coil that would get hot and once it cooled it was good for a few hrs of driving.

I have seen Chevy fuel pumps over heat and not work when warm. Fire truck had that issue and they had one guy under the hood spraying water on the fuel pump so it would stay running while the other guys tried to contain a barn fire.

 

[Mike Groom]

I would lean toward an electrical problem other than fuel, if it's not electronic ignition the condenser or the coil might be the culprit. I have a 1520 and a 301, almost identical tractors and the fuel pump went out on both over the years, it either pumps or it doesn't. It sounds like something is getting hot and then it fails to me.

 

[Janicholson]

new JD owner. I have a 1973 JD 1520 that acts fuel-starved after an hour or so of operation. once it cools some it will start and drive for only a few minutes if that. After sitting for several hours or overnight it runs great for about an hour then the symptoms come back. I replaced the fuel shut-off solenoid because the one on it was leaking at the wire and the insulation was worn through. The tank was drained and inspected with no issues found. No problem found with carb. There does not appear to be a fuel filter anywhere on the line. The tractor is not overheating. I have also tried loosening the fuel cap with no change.

When it happens, feel the ignition coil. if it is so hot you cannot hold it at all, that is likely the reason. As they fail internally they effectively become less and less resistance and that gets them hot. Jim

 

[jamhouse]

I would lean toward an electrical problem other than fuel, if it's not electronic ignition the condenser or the coil might be the culprit. I have a 1520 and a 301, almost identical tractors and the fuel pump went out on both over the years, it either pumps or it doesn't. It sounds like something is getting hot and then it fails to me.

thanks
I suspect Coil didn't think condenser.
I will replace both anyway. It is frustrating. The fuel pump seems to be working fine.

When it happens, feel the ignition coil. if it is so hot you cannot hold it at all, that is likely the reason. As they fail internally they effectively become less and less resistance and that gets them hot. Jim

I will do that today. I had a 1940 Chevy when I was young with a bad 6v coil and carried a bucket of water with me so when it happened I would drop it in the water to cool it. Then get a few more hrs driving.

 

[GeneMO]

Remove the June bug that is floating around in the tank, and gets sucked down to shut off fuel, then floats back up. Someone else mentioned the vent hole in the fuel cap also something to check.

 

[jamhouse]

thanks
I suspect Coil didn't think condenser.
I will replace both anyway. It is frustrating. The fuel pump seems to be working fine.

I will do that today. I had a 1940 Chevy when I was young with a bad 6v coil and carried a bucket of water with me so when it happened I would drop it in the water to cool it. Then get a few more hrs driving.

coil and condenser don't seem to have been the problem.
going to tinker around with it today. i know the answer is there just have to find it'

 

[Bikinkawboy]

Are there any rubber fuel lines? They can swell on the inside when they get older and warm up. Had that on an Oliver diesel on the hose after the electric fuel pump. It would start out fine but gradually run out of fuel until it would die. Cool off and repeat the procedure.

 

[Jim.ME]

Remove the June bug that is floating around in the tank, and gets sucked down to shut off fuel, then floats back up. Someone else mentioned the vent hole in the fuel cap also something to check.

1520 has a standpipe on the shut off valve so it would be hard for one June bug to plug it.

jamhouse, Welcome to the forums.

When you inspected the tank did you remove the shutoff valve and check that the standpipe/screen was not partially blocked?

Did you check the inlet fitting of the carb to see if the screen was still there and its condition?

Those may not be the issue here, and you may have checked both, but they are worth mentioning.