Green Tractor Talk banner

1 - 9 of 9 Posts

·
Registered
Joined
·
117 Posts
Discussion Starter #1
Last weekend I started having some issues with the driveshaft connection to the PTO with my brush hog. While mowing the drive shaft would disconnect from the PTO....it kept falling off. Thought maybe the shaft was binding so made sure it was lubed well and slid easily. That didn't seem to matter. When I pulled the collar back the balls seemed to move freely and when I hooked up the shaft and and pulled back hard it seemed like it was locked in place.

I finally took the coupler apart and found the problem. The piece that holds the balls in place is not in good shape. 31 hrs on the PTO, all with the brush hog. I would have thought it would last longer....

p2897788106-3.jpg

p2897774185-3.jpg

p2897773108-3.jpg

p2897772792-3.jpg

Is this wear from too much angle on the shaft? Shock loads from hitting stumps, rocks and other stuff that I find? FWIW my property is mostly sloped and uneven so the shaft/u-joints get a work out since there is no way I can set the brush hog in one position and mow. It's constant up and down.
 

·
Registered
Joined
·
5,164 Posts
Something's not right

You should not have any problems at 31 hours. We've had mowers with thousands of hours and other stuff is shot- deck, fold hinges, PTO covers etc. but not the couplers.

One thing that can be an issue is if the two halves of the pto shaft are binding. That puts a lot of pressure fore and aft on the coupler. Some shafts have a mid point grease fitting but many require you to slide the two ends apart, grease the inside shaft well and put them back together making sure it goes back the same way it came out so the U joints are in the same plane. If those shafts are dry and binding lots of bad things can happen, not only on the equipment end but also the tractor stub shaft.

Other than that, you may have gotten a bum coupler which is just unusual but possible.

Treefarmer
 

·
Registered
Joined
·
22,086 Posts
First question that comes to mind - especially since you say there is a lot of up and down of the brush hog on your rough property - is the drive shaft the proper length? If it is too long it will jam up when the brush hog raises and put a lot of pressure on the coupler.

With the brush hog in both the lower position and raised check the that drive shaft slide isn’t bottoming out. You would need to check this with the rear of the brush up similar to the position it is in when mowing.
 

·
Registered
Joined
·
117 Posts
Discussion Starter #4
You should not have any problems at 31 hours. We've had mowers with thousands of hours and other stuff is shot- deck, fold hinges, PTO covers etc. but not the couplers.

One thing that can be an issue is if the two halves of the pto shaft are binding. That puts a lot of pressure fore and aft on the coupler. Some shafts have a mid point grease fitting but many require you to slide the two ends apart, grease the inside shaft well and put them back together making sure it goes back the same way it came out so the U joints are in the same plane. If those shafts are dry and binding lots of bad things can happen, not only on the equipment end but also the tractor stub shaft.

Other than that, you may have gotten a bum coupler which is just unusual but possible.

Treefarmer
No grease fitting so I have to pull the shaft apart to grease it. It wasn't super smooth when I first started mowing so maybe that was enough to wear out that piece. The second time I hooked up the mower I lubed it up good but maybe I was too late?

First question that comes to mind - especially since you say there is a lot of up and down of the brush hog on your rough property - is the drive shaft the proper length? If it is too long it will jam up when the brush hog raises and put a lot of pressure on the coupler.

With the brush hog in both the lower position and raised check the that drive shaft slide isn’t bottoming out. You would need to check this with the rear of the brush up similar to the position it is in when mowing.
I believe the shaft is the right length but I will also check that as well. It's all JD stuff from a JD dealer so my assumption is they did right... but I know about ass-u-me ing.....

Thanks for the advice...
 

·
Registered
Joined
·
5,164 Posts
How do you find the old couplers?

I've had similar experience with the "ring type" PTO drivelines.

I use the older style, push pin yoke type on my equipment for that reason.

Yes, the older push pin yoke is more of a hassle, but they are all metal.
I'm amazed you can find the old couplers. I actually find the old couplers easier but thought they were banned as I never see them anymore. We had a machine shop make up some pins to keep a couple of old ones going a bit longer.

Treefarmer
 

·
Premium Member
Joined
·
12,926 Posts
I'm amazed you can find the old couplers. I actually find the old couplers easier but thought they were banned as I never see them anymore. We had a machine shop make up some pins to keep a couple of old ones going a bit longer.

Treefarmer
Tarter (County Line) implements still use the push pin style.
 

·
Registered
Joined
·
117 Posts
Discussion Starter #8 (Edited)
Just an update to this....

The local dealer ordered a replacement kit for the collar. I picked it up and when I opened the box it was obvious it wouldn't work. I think whoever had the kit before me found out the same thing. :banghead: So at 0730 Friday morning I was at the dealership trying to resolve this issue. I took the day off so I could get caught up on my mowing and now I'm chasing parts again. After more than an hour and two guys looking at it, they thought they figured it out but didn't have the parts. Basically I was looking to replace the cross and yolk with the push button style adapter. They called the local Napa and they had the parts so I went there hoping to get some work done.

Napa pulled the parts and it didn't look like that would work either. After another 1.5 hours there was no way that we were going to be able to get the right parts as nothing on the u-joint was standard. The u-joint was some oddball POS. Nothing measured out right and there were no yolks in the book that would work. We ended up replacing the entire u-joint. Cheaper than a new shaft but a lot of time involved. Of course they wouldn't have all of the parts until Monday (yesterday) so there went the day and weekend for mowing. Good thing there isn't a shortage of work so spent the weekend spare time slitting wood and drinkin beer. Sunday it rained all day so it was a day off!

Oh and the cost to swap out the u-joint with a push button adapter was $190 parts and labor. :gizmo: Hope to be mowing again soon. Napa had it done by noon yesterday!
 

·
Registered
Joined
·
12,015 Posts
I'm amazed you can find the old couplers. I actually find the old couplers easier but thought they were banned as I never see them anymore. We had a machine shop make up some pins to keep a couple of old ones going a bit longer.

Treefarmer
treefarmer---jd still had the push button repair kit for my 5ft trailer brush hog available back in 07-cost was $17. we installed it-oh. had to make a few adjustments as we went-oh. my uncle who bought a jd model B-with the brush hog attached--never seen to fixing it either till i got the brush hog from him. everyone just used a bolt thru the pto shaft of tractor.:banghead:

my 3pt frontier spreader came thru with the push-pin deal-i just like the ring collars now-cause i got no strength no more to push the brand new pins in---where as the collars will lock for ya-till u get it on.
 
1 - 9 of 9 Posts
Top