Kyle in KY
Member
I'm having an issue with a JD 5520 hoping someone here could assist with. The tractor has a little over 3800 hours.
While mowing hay, the tractors RPM will drop 100-900 RPMs and struggle to regain RPMs. The fuel filter was changed and seemed to fix the problem, but after two hours, the RPMs started to fluctuate again dropping down to 1300 RPMs from 2200 while cutting normal height hay. No excessive smoking or engine miss is heard when the RPMs drop.
Brought the tractor back to the barn, drained the tank to insure no debris or trash was blocking the 90 degree elbow fitting on the bottom of the tank. The fuel was clean. No water and maybe a teaspoon of small fine sediment out of the tank. No amount of debris to be overly concerned with. Disconnected the line from the tank to the lift pump and disconnected the line from the lift pump to the main fuel filter. Blew air through the lines, no trash or blockage. Connected all the lines, put approximately 5 gallons of fuel in the tank. Turned the key on to the check fuel flow to the main filter. A solid flow with no disparity. Disconnected the main fuel line at the injection pump and turned the key on to check the flow to the injection pump, again a solid flow of fuel.
The return line orifice fitting on top of the injection pump has had the ball valve knocked out, no change. My question, is there a way to check the continuity of the fuel shut off solenoid on the injection pump? I'm thinking that once the engine is at operating temps, the solenoid could be allowing the arm inside the injection pump to move back restricting the flow of fuel. Does this sound like a logical possibility?
The tractor has a Stanadyne injection pump. Any ideas would be greatly appreciated, because I'm stumped at what could be causing the fuel starvation.
While mowing hay, the tractors RPM will drop 100-900 RPMs and struggle to regain RPMs. The fuel filter was changed and seemed to fix the problem, but after two hours, the RPMs started to fluctuate again dropping down to 1300 RPMs from 2200 while cutting normal height hay. No excessive smoking or engine miss is heard when the RPMs drop.
Brought the tractor back to the barn, drained the tank to insure no debris or trash was blocking the 90 degree elbow fitting on the bottom of the tank. The fuel was clean. No water and maybe a teaspoon of small fine sediment out of the tank. No amount of debris to be overly concerned with. Disconnected the line from the tank to the lift pump and disconnected the line from the lift pump to the main fuel filter. Blew air through the lines, no trash or blockage. Connected all the lines, put approximately 5 gallons of fuel in the tank. Turned the key on to the check fuel flow to the main filter. A solid flow with no disparity. Disconnected the main fuel line at the injection pump and turned the key on to check the flow to the injection pump, again a solid flow of fuel.
The return line orifice fitting on top of the injection pump has had the ball valve knocked out, no change. My question, is there a way to check the continuity of the fuel shut off solenoid on the injection pump? I'm thinking that once the engine is at operating temps, the solenoid could be allowing the arm inside the injection pump to move back restricting the flow of fuel. Does this sound like a logical possibility?
The tractor has a Stanadyne injection pump. Any ideas would be greatly appreciated, because I'm stumped at what could be causing the fuel starvation.
