2020 JD PTO malfunction

A friend called me and said the pto stopped working under a light load, he's got a small rotary mower on it, was engaged but not mowing yet, its a small 4' mower actually, and I'm not all that familiar with the mechanical aspect of the drivetrain in a 2020, its live pto, push the clutch half way and it stops. I've run a 6' tiller on this tractor before, no trouble at all. One thing I do know is that this mower looks like a heavy duty model but some idiot, re-used/modified old blades, the outer end has a round hole, and the the other blade is the same, but welded together, it can't be balanced and I know that can transfer back through, I have to wonder if this has anything to do with it. We kinda differ on maintenance, no way I'd even consider running that mower with these cobbed up unbalanced shrapnel blades! It sounds serious, but I have not looked at it, I asked him to check to see if there was any end play in the shaft etc. He said the lever travels the full distance but the pto does not engage or spins. I am wondering how serious and if it will require a split or what can I check to determine what the problem is.

I would bet that he either sheared the pin in the control lever linkage, sheared the center out of the PTO clutch, or maybe broke the shift collar that hooks the front shaft to the rear shaft.

You can drain the hydraulic oil and remove the bolts around the PTO quill and pull it out the back. You can see the shift collar from there but that is all.

If the trouble is in the lever or collar you have to take the rock shaft housing of the top of the transmission to repair any of it.

If the trouble is in the PTO clutch you have to split the tractor for that repair.
Need to look closer and see what the trouble is.

JD, highly appreciated,I thank you for posting the diagram. I had wondered about the 2 shafts, and access with the rock shaft housing off, as it crossed my mind, I'll see what he wants to do, if it does not need to be split he or myself can do it, if it has to, I suppose I could do that too, but don't have much time at the present, however I am fortunate to have a good shop a little north of us, mostly ag land still running older equipment, these guys could easily do that repair, its up to him though, thanks for your help !

(reply to post at 02:25:51 07/09/13)

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It's also possible the pto clutch hub failed.

Billy: If you take the rock shaft housing off, rebuild the three point control valve while you have it off. The orings and back up rings are known to fail with age on the JD utility tractors. Then you have a high pressure internal leak. You will have to re-adjust the draft control linkage anyway.

The biggest problem causing orings and backups are # 26 & 27 but #23 & 24 cause issues too. The solid part# 25 moves a little bit when the linkage is used. It slowly wears the orings and backup rings out.

While you're in there, I really appreciate the heads up, I texted what you said above to him at work around 2am. Its kind of funny, being more familiar with Fords of that era, they are different, but the same things apply, like with the internal hydraulics, some simple inexpensive things in there to check, replace etc. I will copy paste those diagrams for reference. Highly appreciate you posting these !

Only thing that comes to mind is that draft control linkage adjustment, is it complicated to get right, any special tools or just straight forward? I know with the Fords, you need Nuday tools or can fab your own, etc, again I am comparing apples to oranges, but I know you need to use some care once you open one of these up.

(quoted from post at 14:48:56 07/09/13) While you're in there, I really appreciate the heads up, I texted what you said above to him at work around 2am. Its kind of funny, being more familiar with Fords of that era, they are different, but the same things apply, like with the internal hydraulics, some simple inexpensive things in there to check, replace etc. I will copy paste those diagrams for reference. Highly appreciate you posting these !

Only thing that comes to mind is that draft control linkage adjustment, is it complicated to get right, any special tools or just straight forward? I know with the Fords, you need Nuday tools or can fab your own, etc, again I am comparing apples to oranges, but I know you need to use some care once you open one of these up.

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No special tools required just a service manual. The IT books are good enough for this or get your local JD dealer to just print you the pages on adjusting the three point. BE careful and do not drop the socket off the extension while adjusting the three point. Had to take the cover back off to get my socket out, ONCE lol. I tape it to the extension now.

This site had a very good reprint/copy of the original JD service manual. It is $60. Here is the description.

"This is a Service Manual for the John Deere 2020 with 258 pages of important information pertaining to your John Deere tractor.
Full Description: 2020 Gas and Diesel (SN# 117,501 & UP)

This is a reprint of the original factory repair manual and contains the information you need to take your John Deere tractor apart, fix it, and put it back together again. It is the manual the John Deere factory furnished the dealer’s shop service department.

John Deere 2020 Service Manual Part Number: JD-S-TM1044"


If your friend plans on keeping the tractor the $60 would be well spent. They also offer free shipping on two manuals. So I would guess a service and operators manual would get you that.

His dad whom is deceased, and incidentally an army veteran of the late 50's did have a manual for it, he bought the tractor new in '65 I believe, I do thank you for this information, I totally agree, on my side of things, I've always tried to get the correct manuals for everything I own, a good habit I think. I'll see what he plans on doing, he works a night shift, and often times stops by on his way in.

I'd not want to drop a socket in there, a little tape is good insurance ! Thanks again, much appreciated !