You might try cleaning out the groove that the lever sits in the float mode.
Some times moisture gets in the cans on the bottom of the valve and rust, scum will build up. Springs might also be weak. If you go in the cans, lube after cleaning, and insure there is a weep hole for the water.
Had the same problem seems the vibration of bouncing down the driveway is too much for the detent spring. I put a bungee cord on the very bottom of the control lever to take some whip out. Just a little tension is all it took to stop the lever from overriding the detent spring.
I plowed snow this morning and when I put it in float I just pushed it up slowly and it felt like it snapped in place and it worked great. I was just slamming it up quickly before maybe it was not snapping in tightly, so, I am going to keep doing this slowly and see what happens before I operate on it. But, thanks for the info, I'm saving your advice in case I need it. Lee
If I remember correctly my B7500 would also pop out of float when you went over a big enough bump to jar it out. Did it from day one. My Kioti has never popped out, but it is harder to get into float also.
When I get a chance I will disassemble the valve and check out the detent parts. The bungee fix was a temporary thing to get me through the recent storms. I have no problem with the float using the FEL its only when using the plow or blower. Seems the length of the control lever whips around a lot when covering a lot of ground. I will be away from my tractor for a week or so then it will get some between storm maintenance and take a look at the detents. Need to do a quick grease job and oil up the blower chain before the next storm.