Broken jackshaft on Rhino....fixable?

[Richard]

We've got a 10' Rhino rotary cutter. Bought it used. When bought, seems though the seller said it was "field ready" he lied . Just to get it hooked to the tractor we've had to replace the double yoke on the pto end of shaft (about $600), the two yokes and universal at the opposite end (about $400 I think) blades ($150).

During that, I noticed the jackshaft (if that's the right name...?) the 1/2 shafts that go from the main gearbox to the side gearboxes. It's about 13" in length and connects with a rubber shock absorber type thing.

Anyway, with the prior damage of mower, the 1/2 shaft on the same side as bent blade had a visible though small twist in it. Clearly someone hit something and the force bent the tube a bit.

Was cutting field yesterday and the mower was doing GREAT until I found a stump Whacked the stump and now only 1/2 cutting width.

The 1/2 shaft completed its torque and simply spun into two pieces, much like taking a tootsie roll and twisting it while pulling apart.

Now, for the record, I've ordered a NEW 1/2 shaft today ($400) as well as a new set of those rubber connectors, just to have them.

What I'm wondering is, might I be able to get the old shaft repaired by a machine shop?

The shaft has two end pieces, both being grooved to slide onto the splined shafts of each gearbox (center and then side). To the end pieces, they welded a tube. Much like taking the cardboard tube from the center of a roll of paper towels and welding the splined receivers onto each end.

What I'm wondering is, might it be possible for a machine shop to remove the "cardboard tube" section and replace it with something else?

This is really just out of intellectual inquiry as I've already ordered a new one to replace it BUT... if it MIGHT be possible to fix something like that then we might have it fixed and keep it on hand as a fill in should this ever happen again.

 

[dayrunr2]

A good machine shop shouldn't have any problem repairing that shaft. Also, you might check around a shop that builds custom drive shafts. There's a shop near me that custom builds drive shafts for cars and trucks. He has repaired several shafts for me in the past and they usually look better than the factory ones.

 

[Soundguy]

What I'm wondering is what kind of driveline protection are you running? Shear pin? slip clutch? Whatever it is.. it ain't setup correctly..

Soundguy

We've got a 10' Rhino rotary cutter. Bought it used. When bought, seems though the seller said it was "field ready" he lied . Just to get it hooked to the tractor we've had to replace the double yoke on the pto end of shaft (about $600), the two yokes and universal at the opposite end (about $400 I think) blades ($150).

During that, I noticed the jackshaft (if that's the right name...?) the 1/2 shafts that go from the main gearbox to the side gearboxes. It's about 13" in length and connects with a rubber shock absorber type thing.

Anyway, with the prior damage of mower, the 1/2 shaft on the same side as bent blade had a visible though small twist in it. Clearly someone hit something and the force bent the tube a bit.

Was cutting field yesterday and the mower was doing GREAT until I found a stump Whacked the stump and now only 1/2 cutting width.

The 1/2 shaft completed its torque and simply spun into two pieces, much like taking a tootsie roll and twisting it while pulling apart.

Now, for the record, I've ordered a NEW 1/2 shaft today ($400) as well as a new set of those rubber connectors, just to have them.

What I'm wondering is, might I be able to get the old shaft repaired by a machine shop?

The shaft has two end pieces, both being grooved to slide onto the splined shafts of each gearbox (center and then side). To the end pieces, they welded a tube. Much like taking the cardboard tube from the center of a roll of paper towels and welding the splined receivers onto each end.

What I'm wondering is, might it be possible for a machine shop to remove the "cardboard tube" section and replace it with something else?

This is really just out of intellectual inquiry as I've already ordered a new one to replace it BUT... if it MIGHT be possible to fix something like that then we might have it fixed and keep it on hand as a fill in should this ever happen again.

 

[Farmwithjunk]

What I'm wondering is what kind of driveline protection are you running? Shear pin? slip clutch? Whatever it is.. it ain't setup correctly..

Soundguy

Same thoughts here. Torque limiter/slip clutch/shear pin isn't limiting/slipping/shearing as needed. Get the manual on that mower. I'd almost bet someone has eliminated SOMETHING in the driveline. Rhino builds quality equipment. They don't build mowers that self destruct when used in normal conditions. Hitting a stump, while not the best thing that can happen, isn't too far out of the realm of possibility for that sort of mower. I'd suspect Rhino ORIGINALLY built in adaquate protection. Either something is missing or not working as it should.

Outboard shafts can be made to order by a competent driveshaft builder, but would likely cost more as a custom build as opposed to OEM.

 

[sandman2234]

I am not sure having a pto shaft built will cost as much as a factory one shipped to you, as Farmwithjunk suggested, but it might save you the trouble of having to find someone willing to do it on your time schedule and doing quality work. I would catch one of the road crews, or call their office and ask them who does there driveshaft work in your area.
Just out of curiosity, what brand name of gearboxes are on that mower? I have a center and one side gearbox for a batwing that has never been run. I was looking for a used batwing and came across them, but looks like that idea might be on hold.
David from jax

 

[pennwalk]

Usually equipment manufacturers buy pto shafts from someone else. If your shafts are eurocardian Agri supply sells then and they are pretty reasonable. We have a pto shop up the road that can get any part of a pto shaft. Is there one around you?

Chris

 

[Richard]

Soundguy: Setup is with a slip clutch however I presumed my bro in law had checked everything and seems he forgot to look at it so we’re presuming it’s frozen. Since this happening, we’ve loosened it and it’s spinning now. When I put this back together, I’ll tighten it down to speck.

Also, there is only a single slip clutch on the input side of the MAIN gearbox which means you still have the mass of both sets of blades attached to each other. I would have preferred a slip clutch on each of them perhaps, instead of one “main” one.

Farmwithjunk: I’m not thinking the mower is falling apart as we’re using it, I’m thinking we’re simply finding out all the damage that was caused by the prior owner whenever he hit the immovable object he hit that did the driveline damage. This half shaft had a distinctly visible twist in it when we got the machine so in my opinion, it was simply a broken part waiting to happen. Had I NEVER hit a stump (on 250 acres that has been selectively timbered??? Fat chance huh!! Lol) anyway, had I never hit a stump that woud’nt have happened. Guess we’ll see what’s in store in the future.


Regarding Rhino.. I will say this, on two occasions now I’ve ordered a part. I called this part in to my dealer on Monday and the part was drop shipped to me via UPS GROUND and in both cases, it arrived to me the next morning!! I think their warehouse is located in Memphis so me being in Knoxville probably helps. Either way, I’m impressed!!


For anyone who is still reading this, let me change the question a bit...

These half shafts connect between two gear boxes. The end of the ½ shaft has a female splined receiver, the OTHER end has like three “fingers” that attach to two rubber washer type shock absorbers. On the other side of the rubber shock absorber, are three more ‘fingers” that are attached to a part that connects to the OTHER gearbox.

I can only presume these rubber connectors are indeed, some form of shock absorber? I don’t think they’re meant to blow apart if something happens?

Can someone tell me exactly what they’re for if not just shock absorbtion?

Both sides of the mower has these and on both sides, there are some tears in the rubber where they’ve been whacked around every now & then. I ordered a new set of them also as a spare in case they rip through. Would I be better off simply slapping the new ones in or would it be better to wait and let the old ones bite the bullet?

Since the old ones are just “ragged” and not really torn through, I thought maybe use one NEW one on each side, mated with one OLD one from each side (there are two per side). Kind of use the new one to refresh one of the old ones and make two sets out of them.

I hope that makes some kind of sense.

 

[Richard]

If the rubber shock absorbers don't make sense, go here

Rhino : Dealer Locator

and click on the parts manual for the TW-120 and go to page 32 (page 32 on the bottom of the PRINTED page, or page 34 of Acrobats page)

The half shaft that broke is sort of dotted out as an outline and on the right side of it are two 8" circles. Those circles are the rubber shocks I mentioned and the 'fingers' ...well...you can see two of them. The other figers on the 1/2 shaft side are not visible in this picture.

 

[Soundguy]

Howse uses those rubber discs on it's dual spindle hd 120 series mower.. I got one in my back yard right now. Manual is vauge as to their actual purpose.. but deffinately looks like a fuse to me.. My mower also has a TL on the main driveline.

Soundguy

Soundguy: Setup is with a slip clutch however I presumed my bro in law had checked everything and seems he forgot to look at it so we’re presuming it’s frozen. Since this happening, we’ve loosened it and it’s spinning now. When I put this back together, I’ll tighten it down to speck.

Also, there is only a single slip clutch on the input side of the MAIN gearbox which means you still have the mass of both sets of blades attached to each other. I would have preferred a slip clutch on each of them perhaps, instead of one “main” one.

Farmwithjunk: I’m not thinking the mower is falling apart as we’re using it, I’m thinking we’re simply finding out all the damage that was caused by the prior owner whenever he hit the immovable object he hit that did the driveline damage. This half shaft had a distinctly visible twist in it when we got the machine so in my opinion, it was simply a broken part waiting to happen. Had I NEVER hit a stump (on 250 acres that has been selectively timbered??? Fat chance huh!! Lol) anyway, had I never hit a stump that woud’nt have happened. Guess we’ll see what’s in store in the future.


Regarding Rhino.. I will say this, on two occasions now I’ve ordered a part. I called this part in to my dealer on Monday and the part was drop shipped to me via UPS GROUND and in both cases, it arrived to me the next morning!! I think their warehouse is located in Memphis so me being in Knoxville probably helps. Either way, I’m impressed!!


For anyone who is still reading this, let me change the question a bit...

These half shafts connect between two gear boxes. The end of the ½ shaft has a female splined receiver, the OTHER end has like three “fingers” that attach to two rubber washer type shock absorbers. On the other side of the rubber shock absorber, are three more ‘fingers” that are attached to a part that connects to the OTHER gearbox.

I can only presume these rubber connectors are indeed, some form of shock absorber? I don’t think they’re meant to blow apart if something happens?

Can someone tell me exactly what they’re for if not just shock absorbtion?

Both sides of the mower has these and on both sides, there are some tears in the rubber where they’ve been whacked around every now & then. I ordered a new set of them also as a spare in case they rip through. Would I be better off simply slapping the new ones in or would it be better to wait and let the old ones bite the bullet?

Since the old ones are just “ragged” and not really torn through, I thought maybe use one NEW one on each side, mated with one OLD one from each side (there are two per side). Kind of use the new one to refresh one of the old ones and make two sets out of them.

I hope that makes some kind of sense.

 

[MJPetersen]

The little rubber "donuts" allow and are designed to be slop and impulse absorbers. With all those ujoints and shafts and gear boxes there will be some small differences in timing of the pulses and if you had everything rigid it would self destruct in short order. That could be corrected by giving everything a loose fit (slop), but that cause wear and impact damage. The donuts help absorb these impulses while filling in the sloppy fit, which allows the mower to live in harmony with itself.

Mike in Warsaw