Excessive Backlash - Nexstar 5

I just purchased another Nexstar 5 from a fellow astromarter. It arrived with excessive backlash and I can't seem to fix the problem. I have an identical Nexstar 5 for comparison purposes, so I know what it should do. The backlash settings arrived at zero, so I played with them and fixed the "Az" problem with a setting of 60, but even when I set the "Alt" setting to the maximum of 99, I still experience a 5 second delay when using the slew speed setting of 5. In fact, it delays and then jumps when it is ready to move, even at the slew speed of 5. I did open plate under the hand control unit and noticed that the declination motor assembly had all three screws loose and the whole thing would jump from the torque as soon as the power was applied to the declination motor. Tightening them of course fixed the apparent jump of the motor, but did not seem to change anything through the eyepiece. I am wondering if running the scope with them loose for a long period might have prematurely worn the gears to a point where they now need a greater backlash setting than the scope will allow for in its system.

Any ideas for me? I hate to return the scope, but as it is, the "Alt" backlash is unacceptable.

Mark Pacini