(quoted from post at 01:35:43 06/18/20) I can't be sure what year your 540/541 tractor is but the transmission shifter is the same 1 through 4 speed. Your tractor is
stuck in 2 gears, the way you describe it the interlock plug (#16 VT2000 sub to A29060) is worn. The purpose of these interlock
plugs is to prevent the rails from entering an incoming gear until fully out of the outgoing gear i.e. if you are shifting from
1st or 2nd gear into reverse or vice-versa the interlock plug will prevent the the incoming gear rail from fully engaging that
gear until the outgoing gear rail is fully disengaged. The same thing applies to the 3&4 rail with the other 2 rails.
Go to the link, this is the basic shifter for 530 series as well as many other Case tractors. Find #16 interlock plug. The
rails are from left to right reverse, 1&2 gears, and 3&4 gears. The interlock plug between reverse & 1&2 rails usually gets the
most wear. Also less frequently the mesh lock balls (#17) and mesh lock springs (#18) can get worn and shifter can jump out of
gear into neutral. Mesh lock balls are just 3/8" bearing balls available many places.
1 & 2 pics are what I just tried to explain above (forgot I had it) read up on it, better than my rambling.
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto47685.jpg">
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto47688.jpg">
Pic 3 is basically what you see when you pull the shifter cover, for orientation only to show position of forks/rails,
interlock plugs and mesh balls & springs.
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto47690.jpg">
Pic 4 is a worn interlock plug and relatively good condition interlock plug that I removed from a tractor that was stuck in two
gears, reverse and 1&2 shift rails. If you have this condition swapping the interlock plugs will get you reliable shifting
between reverse and 1 & 2 gears until you can replace the worn plug.
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto47691.jpg">
Also we need more pics of the tractor showing dash/gauges, left side of the tractor from front of carb to mid transmission, and
your transmission shift pattern as well as the shift pattern on the cover forward of the transmission where the battery is
mounted.
Joe
https://partstore.caseih.com/us/parts search.html?csid 188c736b515505d119f67ea22e7ab5d7&sl ENcy epc::mr60192ar750218