I was hoping somebody would have an idea the other day I was using my tractor but I put it in slow and it just pops out I can hold it in and it works fine but the minute I Let Go it just pops out
Unscrew the detent cap under the spool (put a bag or something over it before it comes loose). Collect the spring & balls that come exploding out. Clean out the crap in the cap & what not preventing the spring from pushing the balls into the grove on the spool. Grease lightly then reassemble.