25 hp will not stay in reverse with increased throttle

[jms79]

After running onto a sand bar twice and shifting to neutrual, messed up the reverse and drive gears in my 93 25 hp 2 stroke. Replaced gears and now when I shift to reverse and increase throttle, it slips out of reverse and grids the gears. Does anyone know how to correct this problem. I've taken it a part and inspected the gears and there is no damage but, if this contiunues there will be. Please help.

[boats.net]

Recheck shift cable adjustment and check for excessive slack in cable. If thats ok then must have worn shifter parts in gearcase.