PTO shaft Shielding

Rowski · May 20, 2001

Here's a stupid question.

Is the PTO shaft protective shielding supposed to rotate with the shaft or are the chains suppose to keep it from rotating with the shaft?

This is for my Valby chipper, not that it matters. The only info I find in the owners manual (and the warning stickers on the chipper) say the cover NEEDS to rotate freely. If the shaft "spins freely with the pto shaft" what is the function of the chains on the cover. Only thing I can figure is to keep the to shaft from comimg apart when unhooking one end of the shaft.

Thanks.

Derek

Caretaker · May 20, 2001

Rowski,

The PTO Shaft Cover should NOT rotate with the shaft - typically the chains are clipped to some nearby point, and they keep the covers from rotating with the PTO shaft. The idea is to have the rotating shaft NOT be exposed - that's always an accident waiting to happen. Because the covers are held stationary by the chains, and the PTO shaft rotates inside the covers, the covers must always be able to freely rotate on the PTO shaft. There is usually a grease zerk for the cover bearing on each end of the PTO shaft, in addition to the zerks for the PTO Universal Joints.

BTW, the only stupid question is the one that makes you look like an idiot because you didn't ask it! It's ALL pretty simple once you understand it...

As I've said before:
"None of us individually is as smart as all of us are together..."

Caretaker · May 20, 2001

/w3tcompact/icons/laugh.gif

first it wasn't posted, then it was posted, who KNOWS if this will get posted !!!

"Some days you get the Bear, some days the Bear gets you . . ." /w3tcompact/icons/blush.gif

Caretaker

Caretaker · May 20, 2001

Rowski,

The PTO shaft cover should NOT rotate - the chains are typically clipped to some nearby point, and they keep the covers (guards) from rotating with the PTO shaft. The idea is to not have an exposed rotating shaft - always an accident waiting to happen.

Because the PTO shaft rotates inside the cover, the cover has to freely rotate - ergo the grease zerks for the cover bearings at each end of the the PTO shaft cover, in addition to the zerks for the PTO Universal Joints.

BTW - the only stupid question is the one that makes you look and feel like an idiot because you didn't ask it. Trust me - I speak from personal experience... /w3tcompact/icons/blush.gif
"None of us individually is as smart as all of us are together..."

DFB · May 20, 2001

Derek,

I chain the covers on both my tiller and rotary cutter so they don't spin with the shaft. The shielding is meant to prevent contact with moving parts. If the shield wasn't free of the spinning shaft the chains would wrap up right around the shaft. /w3tcompact/icons/shocked.gif

BTW Is all that snow finally gone? /w3tcompact/icons/smile.gif

DFB

Rowski · May 21, 2001

DFB

Thats what I thought. That is the way it was. One of the plastic ears on the cover where the chain hooks onto got ripped off. The cover does rotate freely. I think, I know, what happened. I had to cross a shallow ditch with the chipper on. Because it has quite a long over hang. So I raised the chipper to full hieght. But when installing the pto shaft I hooked the chain to the correct length for the level not all the way up. As you know the shaft gets longer as the angle of the shaft increases. I have been using it the way it is. I know, a no, no. But it's just my father and I around the tractor with no loose clothing. Also the chipper feed is quite a ways away from the shaft. Does anybody know if you can repair these "eyes" that the chain got hooked to.

BTW Is all that snow finally gone?

We had the first Robin of the season yestersday! Just kidding. The snow left about a week to a week and a half behind normal. But the grass is growing right on time. The snow melt was just as gentle. We only had minor field flooding. In late April we were temps in the mid 80's. Most people in the area were pretty amazed, including my self, at the great spring we had!

Derek

Rowski · May 21, 2001

Caretaker

I'll have to check but I don't think there are any bearings for the cover. The cover is plastic. I will take the shaft apart and apply a lubricant so the plastic won't wear out.

Your right about the stupid question.

Thanks

Derek

Caretaker · May 21, 2001

YW, Derek, and my apologies for the multiple posting. Apparently I was trying to operate this thing too early in the morning....

As for repairing the little "ears" on the PTO cover that the chain clips to, it's not easy. The problem is that the plastic is molded, and there isn't much of a place to apply an adhesive. A good epoxy would be strong enough, but unfortunately epoxy won't bond well with plastic - when the plastic flexes, the epoxy will pop right off. You might try getting a fiberglass repair kit, roughing the surface as much as you can, etc. If you still have the pieces, you might get them to bond together. Another notion is to drill a small hole, and use one of those chain connecting links (the kind that screw together) to connect to your safety chain and the cover. HTH...

GlennT · May 21, 2001

I have a Valby with the type of PTO shield you describe. Actually, the PTO shaft is one of those generic things that companies outsource. My PTO shaft is made in Italy and is made by the same company that produced the one on my BushHog shredder. As others have stated, the plastic shield doesn't turn with the shaft and there is a zerk on each end to allow lubrication so that the PTO shaft will turn freely within the shield. I have found that if you simply clip the end of each chain to something relatively close, the plastic shield will rotate enough to wind up the chain around the shield and then you have enough slack to allow you to raise the chipper as high as you might want to. You have probably noticed that in order to release the plastic cup (funnel?) at each end of the plastic shield, you have to press in on three black tabs which hold the cup (funnel) at the end of the plastic tube over the knuckle. This is a pain! When one tab releases, another one re-engages and I only have two hands to press in on three tabs. Oh well, this is really only irritating because I lubricate the PTO shaft at the end of a work day and I'm hot and dirty and sweaty and thirsty and short of patience. However, I do wish they'd redesign this--like maybe have only two tabs 180 degrees from each other?

DFB · May 21, 2001

Here is a diagram from my CT catalog showing the parts breakdown on a typical pto driveline for anyone who's interested. (see attachment)

DFB

jimmoore · May 21, 2001

The Howse rotary cutter that I bought did not have the chains that you mentioned. The shield turns with the pto shaft . If you get against it or grab it it stops turning instantly though. It has the 3 tabs that were mentioned to connect the bells. it does not have bearins only a plastic ring that runs in a machined grove on the pto shaft. It the shield were chained so that it could not spin with the shaft it would most likely only last about 1 hour

jim

Rowski · May 22, 2001

I was thinking about trying the idea of trying to install an eyelet through one of those plastic gussets near the end of the shafts. I'll keep you posted on the fix. Will likely work on it later this week. Lawn needs mowing first. Thanks for the help

Derek

Rowski · May 22, 2001

Jim

I did try to stop the shaft will it was spinning freely. I did use a stick first! Then tried it with my hand. It does not take much effort at all to keep the shield stationary (not turning). The reasoning for my original question. I thought the chain was to keep the pto shaft from pulling apart after you remove the implement. I still need to find out if I have bearings or plastic ring running in a machined grove.

Derek

Rowski · May 22, 2001

Glen

My pto shaft says made in Italy too. I basically hooked up the chain as you describe but must not of left enough slack for lifting the chipper up as high as I did /w3tcompact/icons/frown.gif. I have noticed the three tabs too. I run it to stuff like that in my automotive work, yes it is a real pain!

Which Valby chipper do you have? Do you have the hydraulic feed?

Derek

GlennT · May 22, 2001

Rowski - I have the Model 140; in other words, the stripped-down, direct-drive model. I recently completed a project that took over 80 hours to complete, so I have some experience with it. I like the chipper. It's heavy duty and works well with my little tractor (16.5 PTO). The manual feed obviously is more labor intensive, but it also allows me to easily control the rate of input. The only problem (and it's a significant one) is that juniper needles, small vines or leaves will quickly clog up the machine--especially if they are damp and decomposing. It's really frustrating to have to stop the tractor, open up the shroud and remove the gob of vegetation that is blocking the output chute. I have never seen a Model 160 in use, but I suspect that the greater speed of the disk eliminates some if not all of this problem. Before purchasing my Valby, I considered a BearCat. It was interesting to read a posting recently in which a BearCat owner mentioned that his machine clogged easily, too, even though it had the separate belted impeller, so I guess that some problems are universal. Chipping brush is not one of my favorite pastimes; however, I treasure the mulch as if it were gold. I spread it on areas that are bare or eroding and it is wonderful. It stays in place well, slows down or stops further erosion, keeps the soil cool and moist, and allows vegetation to get a foothold. It's perfect for our caliche hills here in central Texas. I do wish that I could have seen a Model 160 in action before I had to make a decision.

Caretaker · May 22, 2001

Rowski,

All of the PTO Covers I've seen have the Plastic bearing into a metal groove. Not all bearings have balls! /w3tcompact/icons/blush.gif

With reasonable lubrication, it should still last pretty well - after all, there's not a big weight load on the bearing, just the weight of the plastic PTO shaft cover. I throw grease at mine occasionally, they continue to run without screaming... /w3tcompact/icons/cool.gif

and BTW, I have a BearCat 70554 Chipper/Shredder. I finally got to do some serious chipping with it this weekend - it's the proper monster! It had no problem eating everything I put into it, although it did spit out a few pieces - it apparently didn't like the taste! /w3tcompact/icons/laugh.gif Threw 'em back in though, and it choked them right down. Sure does make nice mulching material. Mine does NOT have a hydraulic feed, but the design of the chipper helps to self-feed. I was very happy that we didn't have to stand there and keep pushing the limbs into it - I'm very pleased with it. In the end, we pays our moneys, and takes our chances - nice to have it work out well. /w3tcompact/icons/smile.gif

Rowski · May 23, 2001

Not all bearings have balls!

That's for sure! But I think technically if they don't have balls then the are considered bushings.

The Vably works well too. I love the hydraulic feed. If I'm working by my self, I can throw smaller limbs in the hopper and in they go! Here's a pic..

Where about are you in Western NH?

Derek

Edited by rowski on 05/23/01 01:09 PM (server time).

Rowski · May 27, 2001

Glen

Fixed up the shielding the other night. Used a small eyelet, drilled a hole right next to the original hole, tightened it up and put some J-B Quick Weld on the threads. Worked great!

One thing I did notice with the tabs to get the PTO shielding off is to insert a small thin screwdriver in the little slot on the black tabs. Just put a little pressure (like you would to pull it apart) and pry the lip down one at a time. Hopefully your's is like mine. Also I noticed that on one of those plastic tabs has a hole. It seems to me like a needle fitting on a grease gun end fits into this hole and lube the sheild bushing (one on each end). Take care. Happy Chipping!!

Derek

Harv · May 28, 2001

Jim -

I have the Howse rotary cutter, too. I have been following this thread very closely 'cuz I hadn't had a chance to use the cutter yet. Unfortunately, my tractor and cutter live over a hundred miles from me, so I had to wait until this weekend to see what y'all were talking about.

Now that I've actually seen it again, hooked it up and used it, I can only add the following questions:

What chains?
What eyes?
What ears?
What tabs?

My shaft cover is as smooth as a baby's bottom all the way around the end flanges. No sign of a chain nor any way to attach them if I had them. Like you say, the shield is free to rotate independently of the shaft, but I saw little choice but to let 'em both spin as much as they want.

I've attached picts of my setup. Am I missing something? Not all PTO shields are created equal?

Bird · May 28, 2001

Yep, Harv, I think most of them have a little chain, and a place it's hooked into the shield on each end and you attach the other end of each chain to the implement or 3-point so the shield doesn't turn, but I, too, noticed that the Howse comes without the chains, or a place to hook them. As long as you check it periodically to see that it will turn easily, independently of the driveshaft, I don't see that it makes a big difference.

Bird