how to test John Deere 2305 PTO Solenoid

[gtrgarden1]

The PTO stopped functioning on my Deere 2305 utility tractor. I'm working my way through trying to determine the cause of the problem. I've read some reports that the PTO Solenoid can "lock up" or be defective. I can access/remove the PTO Solenoid just fine, but I don't know how to test it to see if it is functioning properly. I've looked through the Deere Technical Manual for the 2305 and did not find any information about how to diagnose/test that part.
I'm hoping someone can tell me an easy way to test that PTO Solenoid.

 

[WranglerX]

How many wires going to solenoid.... Might be easier to see if you are getting voltage (12 VDC) to solenoid to engage it before you go to deep into this... Have you checked fuses?

Dale

 

[Zebrafive]

I think there a relay(s) involved too. Since you have a tech manual can you post the PTO wiring diagram?

 

[ruffdog]

I think there a relay(s) involved too. Since you have a tech manual can you post the PTO wiring diagram?

Are there safety switches involved too?

 

[Rebeldad1]

if you dont have a wiring diagram start from the pto and go backwards. should only be two wires on it.
put a meter test leads on each one of the terminals on the wire plugging into the pto .
key on sitting in the seat flip the pto switch on. you should have 12 volts going into the pto.
if not check all the fuses. if good follow that pto plug wire back to the next connection. you may have a relay, seat switch, and a fuse to deal with.

 

[gtrgarden1]

Yes, when I engage the PTO switch we're getting 12 VDC (actually about 14 V) at the connector for the PTO Solenoid.
So, I removed the Solenoid from the tractor and tried testing it by connecting directly to a 12V battery. When I do that, the Solenoid shows no signs of life... no click, no pop, no movement at all.
Looks to me like the PTO Solenoid is bad... would you agree?

 

[m1garand762]

When you energize a solenoid coil without being connected to the load the coil will melt. In tje future when you test it off the unit stick a screw driver in the hole where the stem would go then energize

 

[gtrgarden1]

When you energize a solenoid coil without being connected to the load the coil will melt. In tje future when you test it off the unit stick a screw driver in the hole where the stem would go then energize

I pulled the whole assembly from the tractor; so I did NOT just put voltage to the coil by itself.
I assumed that if it was functioning properly, the "stem" would make some sort of clicking noise or show some sign of movement.
But, this is new to me, so I'm hoping for input from others with more experience with these PTO Solenoids.

 

[m1garand762]

If you can put a strong round magnet on the stem and slide it all the way to the bottom you should feel it pull in

 

[RickB]

When you energize a solenoid coil without being connected to the load the coil will melt. In tje future when you test it off the unit stick a screw driver in the hole where the stem would go then energize

And you learned that where? The electrical load is supplied by the solenoid coil windings and is unaffected by the absence or presence of an hydraulic spool in the center of the coil.

 

[RickB]

I pulled the whole assembly from the tractor; so I did NOT just put voltage to the coil by itself.
I assumed that if it was functioning properly, the "stem" would make some sort of clicking noise or show some sign of movement.
But, this is new to me, so I'm hoping for input from others with more experience with these PTO Solenoids.

There should be some evidence of movement. There should also be evidence of magnetism on the outside of the coil when energized. A paper clip or even a small screwdriver will be attracted to the outside of an energized solenoid coil.

 

[m1garand762]

Rick b I work on machines that cost millions that have dozens of solenoids trust me they actually make solenoid magnets for this purpose

 

[RickB]

Rick b I work on machines that cost millions that have dozens of solenoids trust me they actually make solenoid magnets for this purpose

I’m not trusting you for a second when you suggest taking a solenoid coil off a spool housing then energizing the coil will fry the coil. Cause it won’t happen in the tractor world.

 

[BertZegers]

I知 not trusting you for a second when you suggest taking a solenoid coil off a spool housing then energizing the coil will fry the coil. Cause it won稚 happen in the tractor world.

I would not energize a coil without the original core inside, just to be safe.
Most of the electric energy is converted to magnetic energy in the coil. Without the metal core the electric energy is converted to heat.
I have seen coils burnt out / melted if the core was stuck and could not be pulled all the way. Time is the factor here.

 

[RickB]

Well I don’t usually energize a coil for testing purposes and go to lunch. What you really mean is the metal of the valve spool and housing are a heat sink. The magnetic field is created whether or not the coil surrounds the spool, provided the coil is energized and functional. The same amount of energy is converted to heat whether or not the coil surrounds the spool. The coil will not melt into a bubbling pool during a test procedure. A PTO solenoid must be designed for continuous duty, energized for hours at a time.

 

[LouNY]

To the original poster disconnect the wiring to the solenoid and use the ohm scale on your meter to see if it is open or shorted.
Then if your friendly JD dealer has a new measure the resistance of a new one to compare.
It should be a very low resistance value possible even just 1 or 2 ohms.

 

[gtrgarden1]

To the original poster disconnect the wiring to the solenoid and use the ohm scale on your meter to see if it is open or shorted.
Then if your friendly JD dealer has a new measure the resistance of a new one to compare.
It should be a very low resistance value possible even just 1 or 2 ohms.

The reading is about 9 ohms on the solenoid wires.

 

[gtrgarden1]

OK, first, thanks to everyone who has responded to this post.
But, please let me return to my original desire of "I'm hoping someone can tell me an easy way to test that PTO Solenoid."

In other words, if you suspected this part was defective on your tractor, how would you test it to be certain?
I suspect that if you remove the PTO Solenoid from the tractor (the whole solenoid unit, not just the coil) and energize it with a 12V battery, you should be able to observe some sort of function. I was hoping someone has tested one of these before and could tell me what to look for. Should part of the shaft visibly open or close; should it make an audible noise; etc...?

 

[RickB]

OK, first, thanks to everyone who has responded to this post.
But, please let me return to my original desire of "I'm hoping someone can tell me an easy way to test that PTO Solenoid."

In other words, if you suspected this part was defective on your tractor, how would you test it to be certain?
I suspect that if you remove the PTO Solenoid from the tractor (the whole solenoid unit, not just the coil) and energize it with a 12V battery, you should be able to observe some sort of function. I was hoping someone has tested one of these before and could tell me what to look for. Should part of the shaft visibly open or close; should it make an audible noise; etc...?

The easiest and most effective test for the coil would be a resistance test of the coil (which you say exhibited 9 ohms) as compared to the published spec for that particular solenoid.

Without knowing the exact value for a new, functional coil I will disagree with Lou and say 9 ohms is very likely to be within the range of a fully functioning solenoid coil.

 

[gtrgarden1]

I appreciate the advice about the coil. But, let's assume that IF the coil is good, what I'm really wanting some input on is how the "shaft/valve" should react when it's energized by the coil.
Maybe there is a more proper name for it. What I'm calling the "shaft/valve" is the metal parts that inserts into the black plastic coil.


Here's a photo of a new complete Solenoid showing the coil and shaft separated...