Jinma 254 pto engagement

[Whenu]

The other pto gear for comparison. The slider moves to the full range, but when selecting 540, the shaft can still be moved whilst the slider is part way along the gears. on the 1000 gear as soon as the slider moves over the gap between the gears, the gears mesh.
Yep, the oil has had a bit of moisture in.

 

[Whenu]

With selector in neutral.

 

[piper184]

Well there is definitely more wear on the 540 side. It will be interesting to see what the inside of the slider looks like. If you decide to replace the 540 gear it might be a good idea to at least order the slider so you have a new one for comparison. Associated thought, I wonder if you could "flip" the slider so the other side engages?
Let us know how it goes it is good information for future users.

 

[Whenu]

Well there is definitely more wear on the 540 side. It will be interesting to see what the inside of the slider looks like. If you decide to replace the 540 gear it might be a good idea to at least order the slider so you have a new one for comparison. Associated thought, I wonder if you could "flip" the slider so the other side engages?
Let us know how it goes it is good information for future users.

Have orders both. Will see how far the excess wear on the slider is.

 

[ptsg]

Have orders both. Will see how far the excess wear on the slider is.

From what I gather from the pictures, my best guess is that the slider wasn't engaging fully on the 540 side and started wearing out the tip of the teeth on both the gear and the slider. Now it just pops out of gear.

 

[Whenu]

Yep, ptsg, think that's what was happening.

Anyone have taken the pto shaft out before?
Looking at making a plate with tapped holes in, to go over the pto shaft, and pull the bearing and shaft out. Using the pto coupling as an anchor to push against.

 

[piper184]

It looks like the only thing holding the PTO shaft in place is the rear bearing. Remove the outer cover and the seal and bearing come with it. I have replaced the seal before but that is far as I had to go.
After that, I think you can just pull on the PTO shaft and it should slide out and each of the pieces on that shaft will fall off one by one. There does not appear to be any snap rings or other method of retaining shaft in place except a ridge on the shaft that rides on the outer bearing. There is a (thrust?) washer on both ends of the shaft, maybe that is all that keeps it in place.
I wonder if wear on the rear washer allowed the 50T gear to ride farther to the back of the case than designed and that lead to the condition where the slider could not fully engage?
Before you remove the outer bearing cover it would be interesting to see how much end play there is at the PTO shaft and at the 50T gear.

 

[Whenu]

Thought the bearing was housed in the cover and would come out when removing the cover, but it's in the housing. There's no end-play on the shaft and gears.
The large 50t gear, once off the shaft, does it just slide around and get past the wheel drive gears?
Figured that the gears would have to be slid, carefully, off the shaft when withdrawing the shaft.

 

[piper184]

It is good that you have no end play. I checked my PTO shaft today and it does not have any end play either.
This seems a little weird because you wouldn't expect the ball bearings on the output shaft to act as thrust bearings and if they did you would expect at least some detectable end play. Otherwise it would indicate they were pre-loaded and that is not good for ball bearings. So there must be something else holding all this together but I see no indications of anything in the parts book.
On the single speed PTO tractors there is a castle nut and cotter pin on the inside end of the PTO shaft that holds it all together but the two speed does not have that. Something is taking up the slack, but what?
Hopefully the 50T gear will clear the upper shaft and you won't have to take it out.
You might try putting a rod or screwdriver in the hole at the end of the PTO shaft and tapping with a hammer to see if you can get the shaft to back out and bring the bearing with it. It may be a friction fit and not a press fit.
Hopefully someone who has actually done this before will chime in with some "how to's".

 

[Whenu]

Have taken the upper shaft out already, not a problem, did the bearing on that a few years ago. The cast-iron fitting for the bearing is awkwardly placed.