Newbie needs advice on PTO Overrun Clutch problems

I have a few questions and need advice about overrun clutches. Im going to be first-time brush-hogging and Im trying to figure things out. This pin-style overrun clutch (pic A) was on the Ford 860 tractor when I bought it, so I dont know what its been thru. Un-coupled with any implement, it has a LOT of wobble when I engage the PTO shaft. So I went ahead and hooked the tractor and the o-run clutch up to a new 6 King Kutter (yes, it was lubed and gearbox filled). When I engaged the PTO, the shaft was flailing around a bit too much for my liking. So now Im trying to figure out whats causing it, and whether I need a new overrun clutch. No, I didnt hook the cutter up directly to the PTO shaft (yet); Im really nervous about doing that.

I took the o-run clutch off and checked the PTO shaft itself; no play and straight as an arrow. The pin I drove (pounded) out came out bent (pic B). I dont know how I would have done that driving it out. Im guessing this bend would this have been caused by excessive torqueit bent but not sheared.
1. Could the pin alone be the cause of the wobble?, and more importantly, the cause of the excessive flailing-around of the shaft?

Im surprised there arent any YouTube vids on overhauling these things, or at least I could bring up any. Anybody ever done that? 2. What happens when you take out the big snap ringyouve got to have pauls, and cogs and ball bearings and I dont know what all in there. Are they tricky? Or just what all is involved. I need a parts schematic of how theyre made up inside. I dont even see a brand name anywhere. Who makes these things anyway?

3. Do they just wear out beyond repair?, and if so, how can you tell? Any tolerances or play I can measure?

Regarding buying a new one: I like the quick-connect style, and was looking at the one our host offers. But the pin-style does seem to offer a level of protection when the pin shears.
4. Does the quick-connect style offer any protection for the PTO shaft? I cant readily see any in the design.

5. Has anybody ever had damage done to their PTO shaft while using the quick-connect style that may have been avoided with the pin-style clutch?...if so, please share! With my 860 having live PTO/two-stage clutch, do I even need an override clutch? If not, I will probably use one anyway as an added measure of protection. My PTO shaft (pic C) seems to have both the pin hole AND the groove for the quick-connect. If anybody sees a reason why a quick-connect style wont work on this shaft, please let me know. It would be nice to know that BEFORE I order one in.
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If your tractor is an 860, not an 850, then it has live PTO.
You shouldn't have to use the ORC like the non-live PTO needed.
Providing your two stage clutch works correctly.

But yes, the ORC's do wear out and need to be replaced.
The quick couplers are more convenient, but mine is longer than
my pin on one. I'm not sure if they are all made that way though.
 
What model tractor are you using it on?
As Royse said, you don't need (or want) an
ORC on a tractor with live pto.
Also, most new mowers come with a driveline
that is too long to use an ORC with them.
You have to cut the driveline shorter.
If your driveline is too long, when you
lift the mower up the geometry back there
will force the pto shaft forward into the
tractor and booger up the rear pto bearing.
Try hooking the driveline on when the mower
is half height and full height and you'll
see what I mean.
 
The others have given you the correct answers. Just to add a note about these ORCs for reference. If you need one, they get replaced when worn, not overhauled. If you could ID the manufacturer and get parts; the parts needing to be replaced to mitigate internal wear would cost more then a new ORC, to say nothing of the time involved. JMHO
 
I just bought an 850 with the same problem. My PTO shaft has a lot of wear on it and I am replacing it. the pick of yours shows some wear but not like mine has, that could be some of the wobble you have
 

"What model tractor are you using it on?
As Royse said, you don't need (or want) an
ORC on a tractor with live pto.
Also, most new mowers come with a driveline
that is too long to use an ORC with them.
You have to cut the driveline shorter.
If your driveline is too long... "

Thanks for the reply, Ultradog. As I mentioned above, it is an 860 with the Live PTO/two-stage clutch. The shaft has been fitted to work with the full range of lift travel; that part is working great. Problems happen when I engage the PTO. My post seeks more information about the overrun clutch and all the options I can weigh to make decisions.
 
Inexpensive ORCs wear out quickly if not greased regularly. When I used ORCs, I greased them with one shot EVERY time that I used it.

It is not cost effective (or even possible?) to overhaul an inexpensive ORC.

The pin holds the ORC onto the PTO shaft. It does not transmit torque unless things are badly worn. The pin could have been bent by a drive line that is too long.

Are you CERTAIN that your tractor is an 860 and not an 850? Are you CERTAIN that the clutch clevis fork pin is in the proper hole? Why would the PO have installed an ORC onto an 860?

Dean
 

Thanks for the your knowledge and input, Dean. With the tractor running and the PTO lever engaged: when I let up on the clutch pedal a short distance, the PTO starts turning. After a considerable bit more pedal travel, the tractor will start moving when in gear. Is this not the proper workings of a two-stage clutch (making it an 860)?
I still wanted to run an ORC because I want another layer of protection for the PTO shaft, I like the idea of the wear from a free-wheeling implement working against a relatively cheap clutch instead of the PTO shaft bearings and internal tractor components. Any merit to that?
 
Yes. It sounds as you do, indeed, have a properly functioning 860.

As your 860 does not have a PTO brake, I see nothing to be gained by using an ORC and doing so will introduce tolerance into the driveline.

Dean
 

"..., I see nothing to be gained by using an ORC and doing so will introduce tolerance into the driveline."

Okay, you're talking me out of it. So if I disengage the clutch to slow down around corners, for example, the PTO will keep the blades turning @540, and the tractor will have no tendency to push forward. But, to answer WayneIA's comment, and from an engineering standpoint, there are still forces pushing back from the cutter to the PTO shaft as I maneuver through the (shallow) draws and high points in the pastures. So my thinking (maybe wrongly) is that the added tolerance (or slop) introduced by the ORC will be absorbing much of the forces instead of the PTO shaft and bearings itself. I can say to my worn-out ORC: "Well done, good and faithful ORC. You're old an wobbly now, but you served the tractor (and prior owner) well". Meanwhile, the tractor I bought has a PTO shaft that is good'n tight and nice and straight. I'd like to keep it that way. But maybe I'm overthinking it. What's a new PTO shaft anyway, 140 bucks? I'm just a little proud of this thing and I want to take care of it. But if I don't need it, then I don't need it.
 
The blades in the mower will not introduce any added stress to the pto when you step on the clutch part way to go around a corner. This is
because the pto will not slow down so it is still driving those blades.
 
To my thinking, adding an ORC to a tractor
with live pto is a little like wearing a
condom under a flame retardant suit.
You don't need both - at least not at the
same time.

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If you truly do have a 860 with live pto and the 2 stage clutch is working properly you don't need a over running clutch.

That said there are 2 different pto shaft sizes for these tractors, 1 1/8 pto was used till I believe the -01 models came out in late 57
57/up used a 1 3/8 pto shaft, the larger shaft will fit in the older models so one needs to measure the pto shaft to see which one they have.
If you have a 1 1/8 pto shaft and are installing a 1 3/8 over running clutch it's going to be floppy and will bend the pin.

In the 60's we swapped out the 1 1/8 shaft in our 850 for the 1 3/8 shaft, that way we didn't have to run a adapter to use modern implements without having to cut down it's pto shaft, something you wouldn't want to do if it's your neighbors implement.
 
860 has a live pto, no need for an over running coupler. It’s already built into the tractor.

Leave it off.

If you have a 860? Or is it an 850, then it does nit have a live pto.

Paul
 
Sounds like you have an 860 with a live clutch.

No need for the over running clutch for your tractor. It will cause more problems and won’t solve any.

Paul
 
Perhaps your pin was bent due to too long of a drive shaft. If the implement does not have enough travel it could have pushed the shaft too far forward on the PTO shaft.

I use an ORC on my 851 and it shows significant wobble with only 4-5 hours use. Perhaps I abused it a little clearing a forest floor of brush and fallen limbs. As a newbie myself I have to stress the importance of taking your Brush Hog serious. I picked up a 10 pound chunk of concrete along my driveway and threw it a good 20 feet. Not even a scratch on the blade!
 
Pretty much covered in that you don't need/want ORC on that tractor. Good points about pto shaft size and length of implement shaft considerations. Attached shows why not cost/time effective to repair. No bearings, just iron against iron, so grease is required! Splines transmit torque (when roll pin is properly installed), not the pin. Failure to center pin defeats ORC function and does have pin transmitting torque. By bend in your roll pin, I suspect that is what has happened.
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I think you're right, JMOR, we pretty much covered it. It's become quite clear that it's not necessary. This forum saved me 80 bucks or so. Thanks to everyone for your input and advice.
 
Not sure if I should jump in here or start a new thread but I'm like the fiddler and haven't run a pto in a bunch of years. I just got my 1500 and it came with a 715 snowblower mentioned in a thread on the tractor forum. Learned there that with the round shaft on the blower that I either need a pto shaft with a yoke on the end for round shafts or use an adapter. I'm thinking adapter but maybe you guys know better. Anyway the 1500 also came with a 5' TSC finish mower. I thought that all pto shafts were adjustable and will slide but this one is solid and too long to use with the blower.

After reading this thread my basic question is how do you size a pto shaft and are adjustable ones available? Also since this is a dead pto should I use an ORC all the time? With the present mower setup I'll have to live with it and not use an ORC cause I don't want to buy a new shaft for it. I'm not sure an ORC would be needed for the blower anyway. I want to get it working since I have it but it will get rare use nowadays since the big snows bypass us in central KS.
 

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