I have a stringer 800 and when I shift to reverse the motor works very hard and stalls. It is the manual shift type. It shifts to forward and runs strong. It will shift into reverse and the prop does reverse. You can tell it is working very hard though. The lube looked very good top and bottom and the drive sounds better than my old one. The shift cable is like new. The drive is new to me, my old one failed. I don't see it as a shifter cable adjustment because it shifts fwd-rev-neutral from the console with no problem. Any thoughts?