My 2004 25hp mercury want go in reverse all the time when you running it willl work 4 or 5 time then stops going in reverse . I have 2 shops work on it then it does the same thing it not in the cable .I have broke the clip on the end 3 times tring to force it to go . took the lower gears out 3 time and it not that .does anybody now what it maybe ??

My guess-
Stuck at the adapter plate.
Does the shifter/motor feel stiff with the lower off?
What year is the motor/lower?