I know there is a trim problem but it has to do with the lockout arm and not the pump it self. So that is why I am asking were the location of the lockout is.
I don't think there is a reverse lock on an I/O, the hydraulics hold them down, just like on a T&T outboard. The two guys that have responded both know their stuff and I agree with them with the very limited experience with I/Os I have.
That said, I would check the fluid level in your T&T and cycle it several times to make sure the air is bled out. If that doesn't fix it then you may have valve problems.
actually got the answer it is located on the back of the motor, were your throtle cable comes from the captins seat to the rear of the motor that is were the hydraulic line connects to the reverse louckout. but thanks for the help. this is on a i/o set up.
I'm sorry I didn't see this sooner... Yea, the early mercruisers had a reverse trim lockout.... If you have trouble with it you CAN swap in a newer trim pump and ditch the lockout.