John Deere 4600 pto not engaging

[David R18]

I have a 2000 jd 4600 the pto does not work. I installed a new switch.. Nothing. It has not been used much had back hoe attachment for most if the time. Any thoughts

 

[DennisFolsom]

Have you tried checking the connector where the wiring hooks up to the PTO clutch? Maybe it is unplugged, or a bad connection. You might also look for a broken wire.

 

[David R18]

I just removed something that looks like a magnetic switch. The connections were some what corroded maybe cleaning will help. Is there a way to check this switch? The number on it is TSD-09R-01. I greatly appreciate your help.

 

[dws]

Does the PTO light come on? If not, I would check the fuse.

The device that you are referring to (magnetic switch) may be the PTO solenoid. It is located near and under the SCV valve. You can check it with an ohm meter. It should be around 8 - 9 ohms. You can also check to see if 12 volts is present at the connector when the key switch is in run position (engine not running) and PTO switch in the on position.

Also, with everything hooked up (solenoid installed), with the key switch in the run position (engine not running); you should be able to hear the PTO solenoid click when the PTO switch is turned on.

 

[David R18]

Thanks dws, There is voltage at the connector and the ohm meter is reading 10 ohms. I don't here any click from the solenoid but I did notice it does get very warm. I hate to buy a new switch at over $100 but that may be my next move before taking it to the dealer. I appreciate any other thoughts.

 

[dws]

With the solenoid disconnected, you can also check for continuity between one of the leads and the solenoid case. There should be no continuity.

With everything installed, my solenoid does get a little warm. After about 2 minutes, the solenoid is around 105 -110 degrees. The tractor and air temperature was about 80 degrees.

Also, the spec on the solenoid is 1.5 amps.

If all of this checks ok, the next check would probably be the solenoid valve.

 

[David R18]

I think your right. I think it is time for a mechanic. Thanks for your help I will let you know what it winds up being.

 

[David R18]

Well, I have replaced the solenoid valve and had the PTO control valve rebuilt with new seals etc. I have re installed it and still nothing. I don,t have a hydraulic pressure gage but I removed the plug in the pressure test port in the PTO control valve and started the engine and only got a minor amount of hydraulic oil flowing out both with and without the PTO switch on. All other hydraulic implements are working, and I do have voltage at the PTO solenoid valve. I still feel like the problem is in the control valve but am not sure what to do. Any advice would be greatly appreciated.

 

[dws]

I did not find any information in the technical manual for checking the PTO pressures at the PTO valve. I see from the parts list that there are plugs on the PTO valve. The PTO hydraulic schematic shows that the Delay Relief Valve should be 213.6 PSI, and the Lubrication Relief Valve should be 21.4 PSI. The manual doesn't indicate how to check any of this; other than to check the main system pressure. The troubleshooting chart for "PTO will not engage" is as follows:

1. Low Hydraulic Oil Pressure. .....Main hydraulic system pressure should be 2500 PSI.
2. PTO shaft, gear, or bearing failure.
3. PTO clutch worn or damaged.
4. PTO solenoid valve will not engage.

Does your hydraulic system seem to be working normally? Lift for the 3 point hitch? FEL?

 

[David R18]

Yes everything seems to be working properly. I have owned this tractor since it was new and had never used the PTO. When I purchased it I had them install the backhoe attachment and also a hydraulic tilt lever for the box blade. The front loader the 3 point hitch the backhoe and the box blade all work very well. The mechanic that rebuilt the PTO valve said it was pretty dirty, I guess from not being used. I cant imagine the clutch being worn but I suppose there could be some other internal damage caused from lack of use.. not sure. I have copied the instructions on testing the PTO valve below. it would not let me copy the picture of port A but it is on the top surface of the PTO valve above the PTO solenoid and the triangular plate with 3 bolts in it. I am wondering if the channels that take hydraulic fluid to and from the clutch could be clogged with debris and if they can be cleaned out without splitting the tractor or some other drastic measure?
PTO VALVE PRESSURE TESTS
Reason:
To verify hydraulic pressure in the PTO valve is
maintained at correct levels to perform work without
causing damage to the PTO clutch, and to verify that
lubrication oil is being provided to the PTO clutch.
Equipment:
• JTO5487 1/8 NPT X 7/16-20 M 37° Adapter
• JT03017 - Hose With Coupler
• JTO3363 - 0-207 kPa (0-30 psi) Pressure Gauge
• JT03344 - 0-2068 kPa (0-300 psi) Pressure Gauge
Procedure:
1. Park tractor on a level surface and set park brake.
2. Shift transmission to NEUTRAL. Stop engine.
3. Cycle all controls to relieve any pressure that may
be in the hydraulic system.
4. Install adapter, hose, and pressure gauge in test
port (A).
5. Start engine and run at fast idle.
6. Engage PTO.
7. Verify that pressure is to specification.
8. Disengage PTO and stop engine.
CAUTION
Do not maintain pressure longer than necessary.
Pump pressure may exceed working pressure of
flow meter. Relieve all pressure before
disconnecting test equipment

 

[dws]

It appears that there are two tubes between the PTO valve and PTO clutch. Were you able to remove the tubes when you removed the PTO valve?

Could the mechanic that rebuilt the PTO valve determine what the dirt was in the valve?

Have you changed the hydraulic fluid recently? Did you find any clutch material, metal, etc. in the suction screen?

 

[David R18]

There were two short tubes probably 3" long that I was able to remove and they were clean. The hydraulic oil was replaced last year. there was a fair amount of a gray greasy matter in the oil that we never determined what it was but now it looks clean. The mechanic did not elaborate on what was in the PTO valve but did say that one of the internal valves was seized and needed to be replaced.

 

[David R18]

Hydraulic Oil Pressure Specification ±10%
PTO Clutch (Port "A") . . . . . . . . . 1490 kPa (216 psi)
PTO Lubrication (Port "B") . . . . . . . .39 kPa (5.7 psi) 11-26. If pump will not meet specification,
I read Further and found that the PTO clutch port A is supposed to have 216 psi... there was closer to 0 psi. I guess that brings the problem back to the PTO control valve or the PTO solenoid valve.

 

[kbhawaii]

David R18, I have exactly the same problem you have described on my 2005 4520. Were you able to determine what the problem is?

Doug

 

[Henri88]

Doug, David is not a regular poster. You may want to send him a private message. Good-luck!

Henri

 

[CLinton_in_FL]

What where you doing when it stopped?

 

[kbhawaii]

David, thank you for your response. When we took the pto valve apart the first time a small rock came out. I ordered new springs and as we were cleaning out a second time, another rock came dislodged, after re-assembling, it works. Thanks again for responding. Doug

 

[kbhawaii]

Clinton, I'm a coffee farmer in Hawaii, we prune the trees and place the cuttings into the aisle and then use a Rears flail to chew them up. After 2 days of flailing is when it stopped. After dismantling the valve twice, 2 small rocks came out. It's back to working again.

 

[Joe12]

David R18 Did you ever figure out what your problem was? I have a 4500 and mine is doing the same thing.. I have pulled the PTO valve off and I can shake it and sounds like something is in it but I can not get whatever is in it out. any help would be appreciated I'm new to this sight

 

[beenthere]

Joe12
:welcome: to TBN

David R18 has been in-active since 2012, so I'd suggest you try to give him a "wake up" note via clicking on his forum name and sending a PM.
In the meantime, other TBN members may be chiming in to help with your problem..

What is the part no. of that PTO valve?