are you saying that after you installed the water impeller, you now have forward but no reverse gear? If so, do you atleast have water peeing out of the pee hole?
1) Remove your lower unit.<br /><br />2) Determine what gear position the lower unit is in.<br />... Neutral - prop spins freely in both directions<br />... Forward - prop wont turn counter clockwise and will ratchet clockwise<br />... Reverse - prop will not turn either direction<br /><br />3) Adjust the shift selector on the motor to match whatever the position the lower unit is in.<br /><br />4) Re-install lower unit.<br /><br />5) Go boating.<br /><br /><br />(p.s. it sounds like you installed the lower unit with the gearbox in forward gear and the selector handle in neutral. It happens all the time.)