Jinma 254 pto engagement

[Whenu]

Hi all, nice to be here.
I'm having a problem with the engagement of the 540 revs speed of my pto, it seems to be not not engaging properly and jumps out. It engages the 1000 revs speed ok.
The clutch is adjusted to the manual specs.
Is it possible for the gears to have moved or been pushed forward on the shaft? I've had to untangle pampas grass from the shaft before.
Trying to find a solution without having to take the top of the gearbox off.
Thanks for your time.

 

[piper184]

That is interesting. My 284 won't stay in the 1000 RPM setting it keeps popping out to neutral. 540 works fine. Since I don't use the 1000 setting very often my solution is to use a bungee cord to hold the lever where I want it.
I suspect that the sleeve that slides back and forth to choose the speed is not fully engaging the selected gear. This could be due to several things and I have not been inside the rear differential for troubleshooting. A bent fork or poor assembly of the parts may contribute to misalignment somewhere. Another possibility is the detent at the control lever is too weak to hold it in the set position.
I doubt that the clutch would have any effect on the gear selector. I hear you on the trying to avoid digging down to into the gearbox, it is quite a pain. I did it once to diagnose a differential lock problem only to find out it was a loose bolt at the outside of the lever.
There is what appears to be a thrust washer at the front end of the PTO shaft. Perhaps it has too much or too little play and is effecting the meshing of the gears, but you we would have to take it apart to look at it.
Hopefully someone who has dug into this issue before will chime in with advice.

 

[Whenu]

Thanks Piper, thought I had it sorted by cleaning around the detent but it still wasn't engaging properly.
Started cleaning the outside ready for delving in this weekend.
For a reference, I ve attached an exploded view.

 

[piper184]

Same set up as mine. Please let us know what you find.

 

[Whenu]

have found out the teeth on the 50T gear are worn, and presume the teeth on the slider are worn as well.

 

[Agvg]

Are they so worn that it's a problem? Doesn't seem to bad on the picture.

 

[Whenu]

Are they so worn that it's a problem? Doesn't seem to bad on the picture.

Think the internal teeth on the sliding mesh gear are pretty worn too.

 

[ptsg]

When you engage the 540, does the slider engage fully with the narrow teeth? It almost looks that the slider is not moving the full travel and its barely engaging the narrow teeth.

Right now it's on 1000 RPM for the picture, right? So we can the see the shape on the teeth for the 540. The 1000 does seem to engage fully.

 

[piper184]

The teeth look about normal for a synchronizer used in a manual transmission. Tapered on the slider side to aid during engagement. Your gear looks about the same of the picture of a new one I found online. 184.37.457 (5 T Gear for Rear Axle) | Jinma Tractor Parts, Farm Pro Tractor Parts | Circle G Tractor Parts

See if you can get a good look at the inside of the slider with a mirror or something. Also, check for full travel and engagement with the 50 tooth gear. Something doesn't seem quite right here....

 

[piper184]

One other thing, it may just be the lighting but the oil seems kind of milky looking, which might indicate moisture in the oil.