Is this safe? (PTO shaft/rotary cutter)

[bill333]

I bought this used rotary cutter. I'm a bit of a newbie and know that I'm supposed to have some kind of shear protection, like a bolt, but don't know where to find it.

Here is a photo of my PTO shaft and how it is connect to the cutter. As you can see the shaft is welded to the yoke.

(seperately, I'm trying to figure out how to disconnect the shaft from the yoke so I can replace it with a longer shaft)

Am I missing something -- is there supposed to be a slip clutch or a shear pin? Or is the thing marked "what is this" the slip clutch?

I assume if I don't have either then this is not a good setup to run?

 

[aczlan]

On the removable clip question, your clips are on the inside of the yoke, about where my blue arrow is pointing.

The welding of the shaft and the yoke looks normal to me, there was at one time a guard that hooked into the groove on the end of the yoke near where it is welded to the shaft

As to the "what is this" thing I dont know, but if you pull the 4 bolts that hold the cross bracket halves together you should be able to take the whole thing off and that will make it MUCH easier to work on the yoke (trust me, I had to disassemble a similar yoke for our mower conditioner this summer). If it was me adding a longer shaft onto the yoke, I would take off the 4 bolts and take it into a shop and let them change out the shaft, it will be MUCH easier for you and to have the yoke rebuilt on our mo-co this summer only cost ~$30 (parts and labor).

Aaron Z

 

[bill333]

On the removable clip question, your clips are on the inside of the yoke, about where my blue arrow is pointing. View attachment 138288

The welding of the shaft and the yoke looks normal to me, there was at one time a guard that hooked into the groove on the end of the yoke near where it is welded to the shaft

As to the "what is this" thing I dont know, but if you pull the 4 bolts that hold the cross bracket halves together you should be able to take the whole thing off and that will make it MUCH easier to work on the yoke (trust me, I had to disassemble a similar yoke for our mower conditioner this summer). If it was me adding a longer shaft onto the yoke, I would take off the 4 bolts and take it into a shop and let them change out the shaft, it will be MUCH easier for you and to have the yoke rebuilt on our mo-co this summer only cost ~$30 (parts and labor).

Aaron Z

Thanks this is really helpful. I should have cleaned all that grease off the cross to find the clips.
As for lenthening the shaft, that is great advice about taking off the cross bracket (another poster told me that it is the slip clutch). But I can't imagine where I could find someone around here to put on a longer shaft...

 

[greg_g]

Inside clips, interesting concept - I've just never seen any. If you don't find them on yours, my guess is that you just hammer the cross out like any other U-joint. The "what is this" component looks like some kind of primitive slip clutch. Hard to tell from a photo if it's operable - or even salvageable. It would help to know up front what kind of RC this actually (make and model I mean)

As far as lengthening the shaft, you can get PTO driveline components (repair/replacement parts) at or through any farm supply store - or online from places like AgriSupply. But if that slip clutch is frozen - and if the rest of the RC can be considered worth the additional investment - you might want to consider buying a whole PTO drive line. If this is a 5 foot or smaller medium or light duty cutter, you can probably get by with the less expensive shear bolt type. If it's 6 foot or larger medium or heavy duty, I'd spring the extra bucks for the slip clutch version.

//greg//

 

[bill333]

Inside clips, interesting concept - I've just never seen any. If you don't find them on yours, my guess is that you just hammer the cross out like any other U-joint. The "what is this" component looks like some kind of primitive slip clutch. Hard to tell from a photo if it's operable - or even salvageable. It would help to know up front what kind of RC this actually (make and model I mean)

As far as lengthening the shaft, you can get PTO driveline components (repair/replacement parts) at or through any farm supply store - or online from places like AgriSupply. But if that slip clutch is frozen - and if the rest of the RC can be considered worth the additional investment - you might want to consider buying a whole PTO drive line. If this is a 5 foot or smaller medium or light duty cutter, you can probably get by with the less expensive shear bolt type. If it's 6 foot or larger medium or heavy duty, I'd spring the extra bucks for the slip clutch version.

//greg//

Dumb question -- how can I tell if the slip clutch is frozen?

And by a 'whole new PTO drive line" I assume you mean a new PTO shaft? I'd be willing to do that, except I haven't been able to find one that has a spline on one end and the yoke on the other.

It is a 5 ft medium duty Hardee cutter. I only paid $300 for it and if it is going to be a lot of work it might just be cheaper to buy another cutter.

 

[aczlan]

Thanks this is really helpful. I should have cleaned all that grease off the cross to find the clips.
As for lenthening the shaft, that is great advice about taking off the cross bracket (another poster told me that it is the slip clutch). But I can't imagine where I could find someone around here to put on a longer shaft...

You can get a new yoke/shaft (male shaft and half of the yoke) at tractor supply or a similar store. However if you have never taken apart a yoke before I would not recommend it unless you are very good with tools, it has to be put back in just so or it will bind and removing the center takes some creativity with a vise as the inside clip retainers are a PITA to get loose. If you pull the 4 bolts and take it into a decent dealer they should be able to get you the parts you need, and put it together. I would guess that it will run you $60-100 for the shaft (depending on the length and style) and $20-30 for the center of the yoke.

If you don't have a good tractor dealer nearby, you can pull the 4 bolts, take the assembly into tractor supply, have then set you up with a shaft and take the whole thing to a truck repair shop, they will be able to press out the old center and in a new one with your new shaft pretty quickly. You may need to have them take it apart first so that you can get the measurements as to the yoke size and then take them the new shaft.

Where (roughly) are you located?

Aaron Z

 

[aczlan]

You may also be able to remove the whole assembly after removing the 4 bolts and put in a whole new PTO shaft.

Pull the bolts and post some pictures of how it looks.

Aaron Z

 

[greg_g]

Dumb question -- how can I tell if the slip clutch is frozen?

It won't slip. When you get into the rough stuff - wet grass especially - or hit an unseen rock or tree stump - the clutch is suppose to slip before the shock travels all the way up the driveline and breaks something inside the tractor transmission. You need to disassemble/clean/adjust/reassemble - and hope for the best. If it won't come apart, it likely won't slip either.

I mentioned the online AgriSupply as a source. I guess you didn't look. So start here - PTO SHAFTS/ACCESSORIES - Agri Supply - and familiarize yourself with the repair and replacement options.

//greg//

 

[bjr]

Yeah, pull things apart. Get a cheap set like (Harbor Freight sells) digital calipers so's you can measure the yoke cap/bearing bore and the inside the yoke ear to ear distance and 'bout the length to the tractor pto shaft when it's hook up to the mower so you know the median length of the driveline. Call Agri-Supply and tell them what you're doing, they'll probably ask for some of those measurements. Go back with regular six spline 1-3/8" for the tractor end (I'm thinkin' small utility tractor here) and probably smooth bore (you know the size of shaft by now) with bolt hole for shear bolt. Get the low hardness bolts (no marks on the head) to use for shear bolts. The slip clutchs are nice but kinda spendy. The new 5' Bush Hog I bought had shear bolts in it right from the factory. Oh yeah check the grease or oil in the gear head and grease the pto joints. It probably wouldn't hurt to roll the thing up on one side so's you can check things out underneath that something isn't about come apart and the blades swing freely and maybe touch the blades up with a 4" angle grinder (again Harbor Freight tool). I think you'll be happy with the results. Field mowers generally get beat up pretty much so, having new dent free mower isn't the fad. Narly patched up with different paint schemes gives you the Rambo look, much more desireable. Go spend the saved money on the significant other a nice dinner. bjr

 

[bill333]

It won't slip. When you get into the rough stuff - wet grass especially - or hit an unseen rock or tree stump - the clutch is suppose to slip before the shock travels all the way up the driveline and breaks something inside the tractor transmission. You need to disassemble/clean/adjust/reassemble - and hope for the best. If it won't come apart, it likely won't slip either.

I mentioned the online AgriSupply as a source. I guess you didn't look. So start here - PTO SHAFTS/ACCESSORIES - Agri Supply - and familiarize yourself with the repair and replacement options.

//greg//

Sorry, I should have been much clearer in my question. What I meant to ask is, Is there any way to tell if the slip clutch is working without finding out the hard way that it isn't? In other words without running the tractor?

I know the cutter works, I've used it -- but I stopped after reading this forum and wondering if I was in danger of ruining the tractor.

As for agrisupply, I did look at that carefully actually before posting anything. But the descriptions of the products are really only useful if you know the terminology. For example, this the agrisupply description of a PTO assembly:

"8651054 TX1 1110 1-3/8 SPL X 1-1/4R-3/8".

That doesn't help me very much. I can't tell if it is 6 splines or 21. I'm guessing that one end is splined but I don't know what the other end is, or if that other end (Round?) is what I have on my tractor. The photos posted are generic.

I also went to my local tractor supply with detailed pics and measurements. But it is staffed mostly with high school kids, they know less about this than I do, so that doesn't help. They keep very little in stock (good supply of yokes though!) so I can't even find something on the shelves or in the book that looks like what I have.

 

[bill333]

Yeah, pull things apart. Get a cheap set like (Harbor Freight sells) digital calipers so's you can measure the yoke cap/bearing bore and the inside the yoke ear to ear distance and 'bout the length to the tractor pto shaft when it's hook up to the mower so you know the median length of the driveline. Call Agri-Supply and tell them what you're doing, they'll probably ask for some of those measurements. Go back with regular six spline 1-3/8" for the tractor end (I'm thinkin' small utility tractor here) and probably smooth bore (you know the size of shaft by now) with bolt hole for shear bolt. Get the low hardness bolts (no marks on the head) to use for shear bolts. The slip clutchs are nice but kinda spendy. The new 5' Bush Hog I bought had shear bolts in it right from the factory. Oh yeah check the grease or oil in the gear head and grease the pto joints. It probably wouldn't hurt to roll the thing up on one side so's you can check things out underneath that something isn't about come apart and the blades swing freely and maybe touch the blades up with a 4" angle grinder (again Harbor Freight tool). I think you'll be happy with the results. Field mowers generally get beat up pretty much so, having new dent free mower isn't the fad. Narly patched up with different paint schemes gives you the Rambo look, much more desireable. Go spend the saved money on the significant other a nice dinner. bjr

Thanks for the detailed info, this is really helpful for someone like me.
Another poster mentioned an ezhitch that doesn't add any length -- that might solve my problem. I still need to determine of my current slip clutch works. I do know the mower works, I've used it a few times.

I have a 4 inch grinder and I touched up the blades; I don't want them too sharp since this is for a horse pasture. (finely cut grass isn't good for horses!).
I agree totally -- I don't care what it looks like, as long as it works!

On yours, is the shear bolt in the shaft itself, or on the mower? I couldn't find any PTO shafts with bolts at TSC.

 

[kthompson]

Two recommendations: if you call Agrisupply and have your specs they will tell you if they have one and the price. They are great in support. But think you may be better off to forget the $50 or $250 you may save buying there in this case and take it all off and go to local tractor shop that does such repairs. Don't think all dealerships are same for such repairs.

 

[greg_g]

Is there any way to tell if the slip clutch is working without finding out the hard way that it isn't? In other words without running the tractor?

No. As I said; disassemble/clean/reassemble/adjust/test. The test part means mow with it. Short of having instructions on how to adjust it properly, some folks just use trial and error. They put it back together purposefully loose, so that they know it's going to slip. Then - mowing of course - they progressively tighten it until it doesn't slip under normal mowing conditions.

descriptions of the products are really only useful if you know the terminology.

Yeah, the catalogs occasionally aren't really detailed enough for me either. But the spline thing is easy, count'em. Go to the back of your tractor - count the "teeth" on the PTO output shaft. On the mower end, look at the transmission input shaft. It should be quite evident if it's got splines. If it does, count'em. If it doesn't, it's smooth. If it's smooth, put a caliper on it and measure the diameter.

The example you posted is AgriSupply stock number 8651054 (a Eurocardan TX1 1110 PTO shaft, complete). Going to the page specific to that stock number, you would have seen

• made by Eurocardan
• pto shaft TX1 1110 - 43.7" from cross to cross
• 1 3/8x6 spline on the tractor end - implement end is a 1 1/4" round w/a 3/8" set screw

Translation: the tractor end is 1-3/8" diameter and splined, it's 43.7" between the U-joint centers, the mower end is 1-1/4" and round (smooth) with a 3/8" diameter hole in it for a fastener bolt or a shear pin.

But I understand your frustration. Quite often I have to call AgriSupply and talk to them personally, because their not all their catalog items list all the specs I might require. In your case, I think the suggestions to call them with your questions were sound.

If you end up getting the slip clutch to work, you won't need a shear pin. If you don't get it to work, the decision is then whether to replace it with another slip clutch type - or to go with a straight shaft and shear pin.

//greg//

 

[bill333]

greg -- thanks for your detailed reply (and for your service to our country!).
Your explanation was great.
I could not get to the 'more info' page on Agrisupply which had that additional info; just figured out why -- it uses java script to pull up that page, which I try to always turn off (slow, lots of viruses...)

Last question, I hope. When you say it 'slips' when mowing, is this something I would feel? What I wanted to avoid was mowing with a bad slip clutch and finding out it didn't work by my tractor gear box getting wrecked. Am I wrong about this? If the slip clutch is frozen or not working, would the blades simply not rotate?

real newbie, as you can tell!

 

[greg_g]

You'll not likely feel slippage from the operator seat. And depending upon how loud your tractor is, you may not hear it either. The usual indication is smoke coming off the slip clutch. It will probably be squealing too, but you may not hear that.

Don't gamble that "it might work", this is the sort of thing where you need to expect the worst. That's why I'm keep emphasizing that you disassemble/clean/adjust/test. If the slip clutch is frozen or not working, you simply have no protection for the tractor transmission. If/when you hit something stout enough to stop the blades - even momentarily - a tremendous shock load gets transferred through the PTO driveshaft and into the tractor transmission. This is where a properly operating slip clutch comes in. It slips, stopping that shock load right there - preventing it from continuing onward to the tractor tranny. When a slip clutch is frozen - usually because of simple neglect - it can lead to some unanticipated and expensive tractor transmission repairs. Mower damage is just a secondary consideration, comparatively much easier and cheaper to fix.

//greg//

 

[Soundguy]

if a slip clutch is frozen.. it won't slip.. thus no driveline protection.. so when you hit burried treasure.. something gives.. hopefully not something expensive like a tractor tranny.

soundguy

 

[aczlan]

Last question, I hope. When you say it 'slips' when mowing, is this something I would feel? What I wanted to avoid was mowing with a bad slip clutch and finding out it didn't work by my tractor gear box getting wrecked. Am I wrong about this? If the slip clutch is frozen or not working, would the blades simply not rotate?!

A slip clutch is supposed to slip before something breaks in your driveline (ie: one side spins and the other side stays still).

Can you pull the 4 bolts that hold the yoke assy on and take some pictures from directly in front, on the side and behind the disk that is left? That shouldn't be a big deal to do (as long as you dont mind snapping/cutting a few bolts) and let us see if it is a slip clutch and if so, how it should be removed. You will not be able to install a new (shearpin protected) shaft until you get that shaft off.

Aaron Z

 

[bill333]

I'm certainly willing to take it apart for pictures/testing (getting it back together is always my concern!)

This may sound stupid but -- couldn't I test it by (off the tractor of course): blocking the blades (to replicate the blades being 'stopped') and then manually turning the PTO shaft by hand? If the PTO shaft will turn freely without the blades turning, wouldn't that mean that the slip clutch is working correctly? Or am I missing something?

 

[aczlan]

I'm certainly willing to take it apart for pictures/testing (getting it back together is always my concern!)

This may sound stupid but -- couldn't I test it by (off the tractor of course): blocking the blades (to replicate the blades being 'stopped') and then manually turning the PTO shaft by hand? If the PTO shaft will turn freely without the blades turning, wouldn't that mean that the slip clutch is working correctly? Or am I missing something?

If you were able to mow with it you will not be able to get the clutch to slip by hand (unless your strength is more than that of your tractors PTO), think of it as trying to get a car to stand still and burn rubber by standing in front of it.

I would take off the 4 bolts (they shouldn't be a huge deal to replace if need be. However, it might be worthwhile to mark one side with a light colored crayon so that you can get it back together in the same orientation) and look at the bolts that are on the front of the disc (behind the yoke), those look (from your picture) to be where the tension would be adjusted.

Do you know a make and model for this machine?

Aaron Z

 

[bill333]

okay. I think I get it.

The cutter is a Hardee E60.

I already tried contacting the company to see if they have a maintenance manual, but have received no response.