8N PTO Lever Won''t Shift In or Out

Orion231

Member
Ok, so this problem has been getting worse over time. I just got the tractor out to attach my brush hog and found that I could not get the PTO to engage (Lever Won't Move). Took the side cover off and had to tap the shaft fairly hard (yeah, I know, not a good idea) to get it to move forward enough to engage so I can get the work done I need (mowing, plowing and blade work all coming up). I am guessing by all my reading that the PTO shaft splines are probably twisted. Is that a fair assumption as to the problem? I haven't tried to pull the PTO shaft yet but if it won't come out I assume that would be a pretty good indication. If the shaft splines are twisted, what else gets damaged in the process of that?

If I need to replace the PTO shaft, what else do I need to do if the hydraulics would always settle slowly to the ground (faster of course with weight) and not stay up? Trying to decide if I should just use it as is until the fall and then tear into it.

Thanks..
 
I have to ask: do you engage the clutch before activating the PTO Lever? You're not talking about the DRAFT/POSITION CONTROL LEVER either, right? Is the system hydraulic oil up and/or is it contaminated with water -murky brown is the clue here. Water gets into the system, freezes in winter, then damages pump when forced to work without thawing. Don't 'guess' for any problem. Perform true root cause problem solving methods, then determine if part is defective and if so, if can be rebuilt,(1st choice) before buying new. Your hydraulic system sounds like it is severely worn out. It is extremely difficult to 'twist' the PTO shaft. It's made of induction hardened steel and would have to take great force to twist. You would damage the implement PTO drive line and gear box long before the shaft. Get out your Essential Manuals. FO-4 and Owner's manuals have chapters on hydraulic repair. Load dropping fast is the big clue your cylinder is worn and leaking, and probably time for a system inspection and rebuild. Did you perform the leak down test via inspection covers? Pulling the top cover is a time consuming job so you only want to do it right the first time. Get cover and, possibly the pump too, on your bench to inspect before buying any new parts. N's used the 1-1/8" splined shaft until the NAA released the 1-3/8" splined shaft. Only the latter is made new today. The NAA also released the newly deigned cylinder piston with rubber O-Ring and leather backup wiper which works much better than the older 3-Steel Ring Piston on all N's. I highly advise to plan on getting a new cylinder (trying to hone or rebore it never works) as well but wait til you know what all parts you will need and buy all at once. If pump base is cracked due to freezing, it is junk. If not, cleaning and rebuilding are in order. Cylinder, piston, O-Ring & Wiper, gasket kit, new oil, safety relief valve, and maybe more will be need. A new PTO shaft is your call if ya wanna go with new. I also have a document I wrote on 8N HYD REPAIR- email me for LINK.

FORD 8N TRACTOR ESSENTIAL OWNER/OPERATOR/PARTS/SERVICE MANUALS:
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Tim Daley(MI)
 

Yup, engage the clutch when trying to shift the PTO to engage or disengage and really talking about the PTO lever (left side). Fluid gets changed regularly and no water anywhere in the system. I forgot to measure the shaft diameter last night to see which size I have. The leak down is not really all that fast otherwise the hydraulics seem to work fine. The hydraulic lift lever only seems to operate on the upper 1/3 of its travel though.
 
Getting worse over time suggests to me
the pto shifter rail is binding on the
detent ball/ spring. Suggest drain the
fluid and see if the shaft comes out.
Hope it does.
 
(quoted from post at 08:51:23 06/19/20) Getting worse over time suggests to me
the pto shifter rail is binding on the
detent ball/ spring. Suggest drain the
fluid and see if the shaft comes out.
Hope it does.


Thanks, will give it a shot... Don't want to have to split the tractor since I have a lot of work to do on the farm.
 
You don't 'split' the tractor to work on the hydraulic system. You will pull the top cover off, located under the seat. Again I say, it's time for a system inspection & rebuild. ESSENTIAL MANUALS (I&T FO-4; OEM 8N Operator's Manual; & 39-53 MPC) have parts and procedures and the MPC has the visual exploded parts view and numbers. Email me for a copy of my article I wrote for 8N repair. READ everything thru first; there is a specific procedure for removing the system and the 9N/2N is a bit different than the 8N but BOTH are assembled with the hydraulic cylinder bolted with four 7/16-20 square head bolts to the underside of the top cover. Two bolts are shorter than the other two and it matters which ones go where. You need to remove the top cover and get it on your workbench BEFORE you remove the cylinder. If you remove the four bolts before, you will do damage to the system and it becomes a huge mess. A properly tuned hydraulic system will sustain a load in the UP position for several weeks, even months without dropping down. Also, again I say, I highly doubt your PTO shaft is 'twisted'. You can do the 'leak down test' to confirm but by your issues, it's time for a rebuild. If pump base is OK, cleaning chambers and replacing with a new safety relief valve, new exhaust valve, new cylinder, new piston, and gaskets, may get you back running efficiently. Here is a LINK to another good DIY Video---

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Tim Daley(MI)
 
Thanks for the info. I ordered a new lift cylinder and gaskets and may just do that part for the summer. I will leave the PTO shaft engaged but will just remove the brush hog when not in use. Since I need to do some plowing and blade work, I do need the lift working correctly. Hopefully its not the pump but since I don't have along history on the tractor, I am guessing the lift cylinder is probably long due for replacement anyway. If that works, then I am good to go for the summer. Waiting on parts before I tear it down. If I didn't need to replace it, then I just have a spare.
 
Ok, problem solved. The missing detent spring came in and I replaced it under the top cover. It no longer slips out of gear when I let up on the loading.
 
So, finally getting back to this problem. If I understand correctly, I simply remove 4 bolts at the back of the PTO shaft and pull to see if it will come out.

If it does, the problem is in the pump and it will need a rebuild.

If it doesn't, then the shaft is twisted and I will need to cut it out.

If I have to cut the shaft out, do I need to have both the hydraulic top cover and the transmission cover both off or just the hydraulic cover? I have the top cover off and finishing rebuilding it this weekend.

Thanks...
 
I would not put the top cover back on, you will have to do a lot of cleaning and I would drop the pump also.
 
I would not put the top cover back on, you will have to do a lot of cleaning and I would drop the pump also.
 
Looks like I will drop the pump either way and update it. Does this picture show the correct location to cut the PTO shaft if it won't come out?


mvphoto63084.jpg
 

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