3-Point Hitch Broke my PTO Differential Gear Case. Bearings shattered!

[captronr]

In the days of old (before compact tractors), the 3PH arms were longer and the mower/phd/whatever gearbox was further back, so there was less need for precise PTO shaft lengths.

My dealer cut my pto shafts on the tiller I bought with the tractor. I later added Pat's quick hitch, and then the PTO would come apart with the tiller full down. I had to but a new inner shaft and redo it.

Ron

 

[Farmer495]

Thanks for sharing this if it means others will take checking PTO shaft length seriously before hitch up.

I've cut shafts on two brand new 3pt PTO machines, checked and double checked before machine was ever put in gear. Yes it's a pain taking the shields all off and lining everything up but this is why.

Good luck on getting it put back together.

 

[coldsteelva]

The Everything Attachments video on PTO measuring and cutting is a good watch.

How to Measure and Cut a Tractor PTO Shaft - YouTube

 

[CobyRupert]

The problem was the OP knew the shaft was too long, so the "solution" was to rototill with the extendable 3 point hitch arms in the loose extension position (allowing the slightly longer pto shaft to "fit".
The problem came when he raised the 3pth and the extendable 3pth arms slide back and clicked in their proper shortened operational position. Then he lowered the 3 pth with the too long PTO shaft...

 

[Ford850]

The problem was the OP knew the shaft was too long, so the "solution" was to rototill with the extendable 3 point hitch arms in the loose extension position (allowing the slightly longer pto shaft to "fit".
The problem came when he raised the 3pth and the extendable 3pth arms slide back and clicked in their proper shortened operational position. Then he lowered the 3 pth with the too long PTO shaft...

A "famous" quote from Cleveland's mayor Frank Jackson sums this up:
"The problem is we have a problem. It's not that we don't know what the problems are; we've known those for years. It's not that we don't know what the solutions are; we've known those for years. The problem is we haven't done anything about it."

 

[downslope]

In the days of old (before compact tractors), the 3PH arms were longer and the mower/phd/whatever gearbox was further back, so there was less need for precise PTO shaft lengths.

My dealer cut my pto shafts on the tiller I bought with the tractor. I later added Pat's quick hitch, and then the PTO would come apart with the tiller full down. I had to but a new inner shaft and redo it.

Ron

Is it OK to just make the inner shaft longer without increasing the length of the outer? It seems if you do that there would no longer be maximum possible overlap of the shafts and less surface area to transmit loads and resist flexing and twisting.

I'm not saying it's wrong to do, just trying to understand if there's some other reason(s) to maintain the ratio of the shaft lengths or if it doesn't make a difference.

 

[Ford850]

Is it OK to just make the inner shaft longer without increasing the length of the outer? It seems if you do that there would no longer be maximum possible overlap of the shafts and less surface area to transmit loads and resist flexing and twisting.

I'm not saying it's wrong to do, just trying to understand if there's some other reason(s) to maintain the ratio of the shaft lengths or if it doesn't make a difference.

You'll end up with less min-max variance. If you cut one short and leave the other long, that long side becomes the minimum. If you cut them both equal, you still have the same max length and a shorter minimum length. More range.
3 + 7 = 10 (minimum is length of the longest side, 7 in this case. range 7 - 10)
5 + 5 = 10 (min length is 5. range 5 - 10)

 

[oosik]

downslope - I don't know about your ratio question. In the literature I have - showing how to measure & cut a PTO shaft - they recommend a 10" overlap as a minimum. This comes out of the OP manual for my BX62S Wallenstein pto chipper.

 

[Gator6x4]

This is a real bum deal. Right on mikester - cross our toes for his tranny case & bearings. I saw this exact same thing loooooooong ago. So when I measured my pto shaft for my Wally chipper - I set it all up - lined it all up - took measurements - cut a piece of quarter round wood molding to the total overall length - then cut this length to what each half shaft would be - held it in place while the wife raised/lowered the 3-point. Shut everything down. Came back the following day and went thru the exact procedure - got the exact same cut length measurements and cut half what was necessary off both sections. I ended up with 12" of shaft overlap and they are 3" from touching at the closest.

I mean - how often does a guy really get any experience dealing with pto shaft measurements and cutting. For me - the pto shaft for the chipper was a one time deal and I probably will never have to do a pto shaft again.

File this away for the next time. How To Measure And Cut A PTO Shaft

 

[downslope]

You'll end up with less min-max variance. If you cut one short and leave the other long, that long side becomes the minimum. If you cut them both equal, you still have the same max length and a shorter minimum length. More range.
3 + 7 = 10 (minimum is length of the longest side, 7 in this case. range 7 - 10)
5 + 5 = 10 (min length is 5. range 5 - 10)

What I was questioning was that captronr said his dealer had shortened the tiller shaft when he made the purchase. Then at a later date he installed the Pat's hitch and found it necessary to lenghten the shaft. He did that by just replacing the inner shaft but not the outer. Assuming the dealer cut both sides equal like you're supposed to, then by just replacing only the inner part later on you would end up with a greater length of inner shaft that was not being overlapped.

I was just wondering if that would be OK? Someone said his chipper called for minimum 10 inch overlap. So maybe it's OK to not have both halves equal, as long as sufficient overlap, but you would lose some range at maximum extension

 

[Fallon]

If you cut half a shaft short, the long half will still bottom out & cause problems. It doesn't matter if the inside or outside is long. The end of the long shaft will still hit the yoke for the U joint.

You don't have to get things cut perfect, but both halves should to be in the same ballpark. If the long half is short enough to not bottom out by a couple inches in use AND there is enough overlap (generally 1/3 of the shaft length) you should be fine.

 

[CobyRupert]

Typically one can eyeball and test (prior to hooking up the pto) at what 3pth, and attachment height, results in the shortest PTO shaft requirement.
In most cases this is when the attachment's pto shaft is straight back and level. (results may very, as there may be some attachment configurations where the shaft gets shorter as the equipment is lowered or raised.)

I figure that if the pto shaft can slide short enough, with hopefully a few inches to spare, to attach to the tractor at this height, then there must be a few inches of safety cushion once the pto shaft slides/extends onto the tractor's spline and clicks in.

 

[V7Sport73]

The problem was the OP knew the shaft was too long, so the "solution" was to rototill with the extendable 3 point hitch arms in the loose extension position (allowing the slightly longer pto shaft to "fit".
The problem came when he raised the 3pth and the extendable 3pth arms slide back and clicked in their proper shortened operational position. Then he lowered the 3 pth with the too long PTO shaft...

Yes, that is exactly what happened. I do have a quick hitch but was anxious to try my new tiller.

 

[V7Sport73]

Parts arrived today. Interestingly enough the new differential case was not painted. I got started on the break down on the tractor. About 4 hours so far. I carefully removed each part returning the bolts into the holes that came out of. I also labeled parts that might be difficult to remember which direction they are mounted.

 

[V7Sport73]

Moving along I have the differential off. Getting ready to reassemble everything. About 8 hours working on it so far...

 

[Ford850]

Nice progress. Are you still taking to a shop to get the bearings reset?

 

[dodge man]

Nice job so far. I like people that when they break their stuff, they don't whine about it but step up and fix it.

 

[hawkeye08]

I've read about things like this and made a mental note to check shafts before hooking up, have forgotten each time, could have been a disaster. Hope I remember to check if I ever buy another implement. Expensive lesson to learn.

 

[George the Beagle]

You're not afraid to tackle what to me would be a big job, fraught with all sorts of opportunities for me to screw up. I'm impressed.

 

[JB13502]

Following with interest. Thank you for including some great pictures! :thumbsup: