TC34DA -- PTO won't disengage

[amarlow]

I am having trouble with the rear PTO on my 2006 TC34DA, and am hoping to tap the TBN knowledge base for some help and direction. Any ideas would be most welcome.

This year I decided to have the spring maintenance done by a professional, so someone with more experience than me could look for any problems or issues which I wouldn't even see. I took the tractor to a well known equipment dealer; they don't sell New Holland, but do know tractors and hydraulics. The service included oil change; replace all filters (oil, 2 hydraulic, fuel); axle fluid and hydraulic fluid check (drain a bit, look for metal flakes, water, other bad stuff) then top off; grease all fittings.

I am telling you all of this because I had just gotten the tractor back a few days before when this PTO misbehaviour showed up. I don't know that there is a connection, but you might think differently.

So the PTO problem: I am not able to disengage the rear PTO as I have been for the past three years and 350 hrs. This has only happened a few times, but has become increasingly difficult very. I rely on the rear PTO for rotary mower work, primarily. Since retrieving the tractor from the maintenance service place, l probably engaged & disengaged the PTO/mower a couple dozen times over a few days before this problem showed up.

I am not really sure how I was able to eventually disengage the PTO the times this happened. I tried a myriad of things, and not sure what worked. I changed engine/PTO speed, I shifted gears, in gear, out of gear, turned on my headlights (OK, kidding about that one). I even tried killing the engine, then moving the lever in and out, but then wasn't able to restart.

I said this problem only manifested a few times (six? eight?). During two or three of the "eventually successful" attempts to disengage, I managed to only partially disengage (I'm guessing here, cuz I don't know how the PTO drive is configured inside). I assume there is a similar spline on the interior end of the shaft that sticks out the back, and moving the on/off lever outside moves a female over that shaft to engage the spline. But these two or three times I heard very audible clicking, as if the male and female teeth were clattering over each other.

At some point in all this trial and error, I noticed I had moved the front PTO lever to the "on" position. I have no idea when this happened, and don't know whether that affected anything inside or not. This was the time I had killed the engine, then not been able to restart. When I moved the front PTO lever back the "off" position, I was able to start.

I have checked & lubricated the linkage and both pivots. I have adjusted the final linkage arm, the one connected to the shaft entering the case, made it both longer and shorter by moving the yoke a few threads (quarter inch up and down), with no apparent effect (so I put it back where it started).

Since I bought this tractor (in 2010, w/ 90 hrs on it), disengaging the PTO (ie. moving the lever at the left of the seat rearward to the "off" position) has been not exactly difficult, but certainly not easy or smooth. I only recently learned of the option of doing the engaging/disengaging at low RPM and then changing engine speed when when I was ready to use the mower. The fellow I bought it from was the one who said I needed to engage/disengage up at 540 PTO RPM (~2500 engine RPM).

I can't think of any more info which might help. I tend to write way too much anyway, but want to give all the data possible, in case one of you says, "Oh! That's the problem."

I think it's time for me to suck it up and purchase the repair manual.

I'm looking forward to any help and advice. Thanks.


~Allen

 

[jinman]

Allen, what do you do with the clutch? Doesn't your clutch disengage the PTO?

 

[amarlow]

I always push in clutch pedal to the floor while shifting the PTO lever from disengaged to engaged or vice versa. And yes, if the clutch is depressed, then the PTO output shaft stops spinning.

 

[jimmysisson]

PTO should be engaged with depressed clutch and engine at low idle. Let out clutch at lowest RPM implement requires, then adjust speed to operating range.
If the prev owner always engaged the PTO at full rpm you might have some burrs on gears or shafts. That could happen with slightly careless clutch pedal work.
At 350 hours this rig should be in its prime.
Have you opened up the gear case yet?
Jim

 

[amarlow]

I have not done anything to it, yet. Not even sure what "open up the gear case" would entail. I don't have a protected shop (yet) where I could do much in the way of engine or transmission tear down. Is there any other way to inspect the innards, try to isolate the problem, without removal?
~Allen

 

[jinman]

Allen, Jim makes some good points about burring the gears, but I think before you tear into something, you should do a clutch adjustment. If you clutch is not fully disengaging, you won't know it with an HST transmission. However, if there is torque to the PTO shaft, it would make it hard to engage and disengage. It might grind a bit on engaging and be really tough to disengage. I think I'd do a clutch adjustment to make sure it is fully releasing before doing anything else.

 

[amarlow]

Thank you, Jim(s). I appreciate the time.

I am out at the (vacant) property now, so am having to write this on my phone. I do have my tool box with me. Jinman, can you describe how I would go about adjusting the clutch? Is this the PTO clutch? (called something like a sprag clutch??). I am going to purchase a copy of the shop manual, but for the moment I am relying on outside support for instructions and images. Again, I appreciate the time and help.

 

[jinman]

No, I mean the main clutch. If your pedal has more than 3/4" of play, it could mean that the pedal cannot disengage the clutch fully. I don't know the exact steps for your machine, but you can easily check the free play in the pedal before it starts to engage the clutch. If you look at the clutch linkage, you might even be able to figure out how to adjust it. Maybe somebody with experience with post how it's done on your tractor.

 

[amarlow]

Finally home. Lots of seat time today, none with the PTO (though I really need to use the mower). I bought this property 3+ years ago, completely vacant, not even a shed. No well, no septic, and no electricity. We've been working since on the preliminary stuff: cleaning up years of fallen limbs and trees; taking down dozens of large (20-30 inch) standing dead ash trees (killed by the emerald ash borer); clearing a 72x140 garden space; planting the perennial garden veggies and berries; and a 20 tree mini orchard. Now I'm ready to move on to real buildings. The barn is first, as soon as I figure out how I want to do it.

Right now, I am working with Detroit Edison to bring in power to the barn site. There is a pole just off the north border, and DTE is going to route (underground) from there, almost due south, ~350 ft, to a pad mount transformer, which will ultimately feed my meter. It's my responsibility to provide a clear path, minimum 10 ft, preferably 20, for the trenching and easement. Most of the 350 ft is already clear, but my kids and I worked for 10.5 hrs today, nonstop, no breaks, on a section of woods that comprised 80 or 100 of the 350 ft. It was primarily small seedling size stuff, some saplings in the 3 to 6 inch range, and a few larger trees. The tractor was used for the saplings and larger trees. The weather was perfect. It was a good day of hard work. I'm wiped out.

Thank you, Jim, for the clutch adjustment explanation. In the past, when the pedal was depressed, and I moved the PTO lever to the on/engaged position, and then began to let the pedal out (to engage the main clutch), I have had to come almost all the way back out, to the "pedal not depressed at all" state, in order to spin up the PTO.

I will investigate the clutch play and adjustment when I'm back out there again, tomorrow. Again, thanks for all your help.

~Allen

 

[jinman]

It would be great if the main clutch was your problem, but I think that's just something you need to check before looking at something else. The PTO on my tractor is completely independent and has its own clutch/brake, but yours is nothing like mine. That's why I can't be much help except for what I see on the online parts diagrams. One diagram has the levers, one has the PTO drive gear, one has the transmission gears after the HST (range gears) and another has the clutch. Trying to put all those together for a complete understanding of the PTO drive is a challenge. I just hope I'm not sending you off on a wild goose chase. I was really hoping someone else who knows your driveline a bit better would give some insight, but it can take awhile for people to see your post and respond. That's just the nature of an online forum.

It sounds to me like you are making great progress on your property. You've got an ambitious schedule and tasks that are daunting. Those of us who have bought unimproved land with no facilities or utilities and did all the improvements know how much work there is and how long it takes. I look back with amazement at the 1st day I stepped foot on my property when it was all weeds and woods. Like you, I had coop electric service within 400' of my site and landline telephone service along a county road. I've done everything else.