MX5200 No PTO and no POWER

[doesleap]

I have an MX5200 HST that is 3.5 years old with about 900 hours on it. The initial problem I had with this tractor was back in September when I lost power to the PTO (just as I started to bale hay). I checked the PTO seat switch, PTO solenoid, and various other things and they were all good.

Shortly after this incident, I would lose all power to the tractor if I depressed the HST shuttle/lever more than 10-15%. I could rev up the power all I wanted but as soon as I asked the tractor to go beyond a creep, it would lose power to the point of stalling. Thinking this was a fuel issue, I checked to see that I was getting good fuel flow beyond the lift pump (all good there).

Another wrinkle: the power and PTO problems are intermittent. The tractor can work fine for days, and then the symptoms re-emerge.

I finally shipped the tractor to my local dealer who told me the problem was the PTO seat switch which they kindly replaced for $600 (not including trucking). As many of you know, this is a 5 minute job...tops.

Needless to say, this did not solve the problem although I have been able to use the tractor on and off the past couple of months. Yesterday, I lost power again. This morning the power issue was resolved, but the PTO would not engage.

I am nearly 100% convinced that these are related hydraulic problems and would appreciate any help in narrowing down a possible solution. I do have a shop manual for this tractor and would be happy to upload any schematics to help address my problems.

Thanks in advance.

 

[lugbolt]

sounds like they had to replace the whole seat. Not uncommon, explains the expense.

Stalling sounds like a fuel issue, or more specifically a fuel FLOW issue. Something restricting fuel flow? Separator inlet plugged? Does the separator fuel level drop when the tractor loses power?

 

[TheOldHokie]

I have an MX5200 HST that is 3.5 years old with about 900 hours on it. The initial problem I had with this tractor was back in September when I lost power to the PTO (just as I started to bale hay). I checked the PTO seat switch, PTO solenoid, and various other things and they were all good.

Shortly after this incident, I would lose all power to the tractor if I depressed the HST shuttle/lever more than 10-15%. I could rev up the power all I wanted but as soon as I asked the tractor to go beyond a creep, it would lose power to the point of stalling. Thinking this was a fuel issue, I checked to see that I was getting good fuel flow beyond the lift pump (all good there).

Another wrinkle: the power and PTO problems are intermittent. The tractor can work fine for days, and then the symptoms re-emerge.

I finally shipped the tractor to my local dealer who told me the problem was the PTO seat switch which they kindly replaced for $600 (not including trucking). As many of you know, this is a 5 minute job...tops.

Needless to say, this did not solve the problem although I have been able to use the tractor on and off the past couple of months. Yesterday, I lost power again. This morning the power issue was resolved, but the PTO would not engage.

I am nearly 100% convinced that these are related hydraulic problems and would appreciate any help in narrowing down a possible solution. I do have a shop manual for this tractor and would be happy to upload any schematics to help address my problems.

Thanks in advance.

Symptoms are 100% consistent with a bad OPC switch or circuit.

I am inclined to think the dealer was on the right path but failed to to find and fully correct the problem in that circuit. Have you talked to them about it?

Dan

 

[doesleap]

sounds like they had to replace the whole seat. Not uncommon, explains the expense.

Stalling sounds like a fuel issue, or more specifically a fuel FLOW issue. Something restricting fuel flow? Separator inlet plugged? Does the separator fuel level drop when the tractor loses power?

The fuel does not drop in the separator when I lose power. I have good fuel flow after my pump.

 

[doesleap]

Symptoms are 100% consistent with a bad OPC switch or circuit.

I am inclined to think the dealer was on the right path but failed to to find and fully correct the problem in that circuit. Have you talked to them about it?

Dan

OPC circuit? I checked the PTO switch, and seat switch and determined that I am getting power to the PTO solenoid. Anything else I should check? Thanks.

 

[TheOldHokie]

OPC circuit? I checked the PTO switch, and seat switch and determined that I am getting power to the PTO solenoid. Anything else I should check? Thanks.

Dont know the circuit.. WSM should show what signal needs to be present to enable operation of the HST pedal.

 

[doesleap]

To tackle the problem of no PTO, I wired the PTO solenoid directly to the battery and everything worked fine (i.e. the PTO turned on and off). I then traced the wire that provides power to the PTO solenoid all the way under the dashboard where it terminates at the Electronic Control Unite (ECU) that controls the safety switches. My dealer loaned me a new ECU to see if that solved the problem. It did not. The next step is to determine what powers the ECU and see if I can find a short somewhere in the system. My WSM does not have a wiring schematic for this ECU. Does anyone have access to this? Also, any thing else I should check?

Thanks!