Oliver 1800a gear jumper

[Sam WI]

I have an 1800 checkerboard that jumps out of 4th and all the gears in that range. 4th being the most common to jump. You can hold the shifter in gear and it stays in gear just fine. I pulled the top cover on the transmission and don't see anything obviously wrong inside. Any thoughts would be appreciated.
 

[super99]

Shifting fork bent and not fully engaging the gears???????
 

[J. Schwiebert]

I started working on Olivers's when they were new. I will need a serial number and a phone number. My e-mail should ne open.
 

[J. Schwiebert]

Most likely your problem is on the top shaft. I need to remember from 50 years ago.
 

[ziffel]

Shift rail detents. Broken spring, bad detent or bad rail.
 

[Sam WI]

The coupler on the top shaft has some wear
between it and the fork. This should be the
coupler that engages high and low range
correct?
 

[Sam WI]

Serial number is 120 836 892. My phone number is 608-206-3796.