PTO slip clutch - bad or?

[DieselBound]

I'd worried that the slip clutch on my PTO shaft (bought new a few years ago- Bare Co.) for my bush hog wasn't slipping: I cannot recall whether I'd previously taken this one apart and cleaned it up or whether it was the one that I'd had when I originally bought the bush hog (used - the original shaft didn't last very long- it was crap when I got it). I loosened it up and ran for quite some time to ensure it was actually able to slip and not froze up. I saw (marks I'd made) that I'd gotten it to slip. At one point, I think before I decided to set the spring lengths proper, I saw some black smoke poof out. Once adjusted to "spec" I ran it for quite a while with no apparent signs of problems. And then today... While mowing in some very tall, heavy and wet grass I saw it start to smoke: saw white smoke. I backed off and decided to just finish up mowing in some much shorter stuff, but I saw that it was still struggling, still wanting to smoke, so I decided to call it a day. Though hot, I could see no obvious signs of overheating or missing chunks of the clutch plate. Before taking it apart I'm wondering if I can just tighten it up. Here's why I am considering doing so (I know it's not something that you really should do)...

I have TWO different specs on the spring length. The PTO shaft manufacturer (Bare Co.) says 1.18", which is what I set the springs to. Bandioli and Paves (the style or the actual manufacturer of the slip clutch?) says that it should be 1.10". Not sure if tightening 0.08" would make much difference.

Perhaps things are glazed and I might be able to clean up? Yes, I probably should just take it apart, but I'm kind of curious as to what all sorts of problems these things can have: this is the only one I have (or have had).

 

[mwayne]

Sounds to me like your adjustment is pretty close. Add an eighth of a turn to each bolt and see if the slipping improves. I regard the spec provided by the slip clutch manufacturer as a starting point. Good luck!

 

[Sawyer Rob]

There's NO known adjustment for YOUR tractor! Tighten it up until it stops slipping.

Also, every time you slip it, you are making the plate in it thinner, so you have to compensate for that...

SR

 

[DieselBound]

I was concerned that at the least I might have glazed it. That it seemed to easily slip on lesser grass, once out of the ugly stuff (a good 6' to 7' tall), I got concerned that it might be toast: I believe that I did catch it early in which case I'd like to think that I couldn't have done any real damage to it.

 

[RoyKing]

Here is how I set mine after a rebuild, new clutch disc's. Tractor at idle, someone else in cab to turn PTO ON. Upon engagement I adjusted till my blades came upto speed in about one revolution of slip. Went out and chopped down a bunch of pine saplings 3" and under worked great.

 

[DieselBound]

I can say that my clutch didn't smoke this bad (and they continued to run it):

ABSOLUTE DESTRUCTION! Large Brush Mulcher, Deere 5410 - YouTube

Tomorrow I'll tighten it up (shoot for 1.10") and see how it goes.

 

[Texasmark]

I prefer the bolt. On the stuff I buy with a clutch, at the start of the season, I measure the thread length and then back off the bolts till it slips. Let it slip at low PTO speed for a couple of minutes. Retighten the bolts to the previous thread length. If it slips when encountering heavy material, tighten bolts a bit at a time till it stops. Other thing is that I keep them under a shed. That way condensation moisture generated rust is all I have to scrape off.

 

[Sawyer Rob]

I'd take a blk. marker and put a line on each nut. (so you can see it go around) Then tighten them all 1/2 to one turn each.

Run it, and if it still slips too easy, go another round tighter on each nut...

SR

 

[Zebrafive]

I'd take a blk. marker and put a line on each nut. (so you can see it go around) Then tighten them all 1/2 to one turn each.

Run it, and if it still slips too easy, go another round tighter on each nut...

SR

I am able to use a ratchet/socket on my slip clutch nuts. So I put a ring of masking tape on the socket, then use the marker to mark a line. Then I can tell how far I turn the nut. I do not have to remove the socket to see a mark on the nut and it I "ratchet" I do not lose count if I were just trying to count turns/partial turns of the ratchet.

 

[Zebrafive]

I assume once the friction disc is glazed it's ruined? Is that correct? Or can it be saved?