Hi everyone. I am a new member here but have been lurking in the shadows for sometime and have obtained a lot of very valuable information from members at this site.
Just last week I was using my Jinma 284 to do some loader work ( feeding the BIL's bulls some sillage) and noticed that the shifter wasn't working right. It had too much side to side play and it seemed that I could get it in 2 gears at the same time. Needless to say, I was concerned and pulled the shift cover off.
The shift cover on my 284 is a bit different, in that the gearbox cover, shift tower and Hi/Lo shift tower(?) is all in one. No seperate shift tower as on Valley's tractor. The inner workings are basically the same.
What I discovered was that the bolts that hold the shift guide plate secure had worked loose or were not tightened at the factory. The front bolt was very loose and the back bolt was completely out. Luckily, the bolt and retaining clip were still laying on top of the shift rails.
I would hate to think what could have happened if these parts had fallen into the gears.
To fix the problem I drilled two small holes near each bolt hole in the shift guide plate, drilled a hole through the head of each bolt, discarded the retainer clips, installed a lock washer on each bolt, tightened the bolts and safety wired them to prevent them from coming loose again. This was a simple inexpensive fix.
I would suggest that the tractor in question not be used until this is checked and fixed. If the bolt(s) have come out, and get into the gears it will be an expensive fix.
Sorry this is so long, but I hope that what I found will help others.
Hillside2008