Re: Merc 400 water pump repair
Make sure the lower unit goes up perfectly straight, to align the driveshaft with the crankshaft splines. You'll probably need to move the flywheel in a clockwise direction, while pushing upwards on the lower unit, until the splines in driveshaft and crankshaft align. Be sure the spark plug wires are pulled before rotating the flywheel!
Also make sure the upper shift rod is lining up with the shift shaft in the lower unit. If you have to, disconnect the shift cable from the motor and move the shift arm to and fro ever so much, to allow the splines to align.
Last, ensure the water tube lines up to go into the water pump housing. A strong light helps to see the water tube as you're assembling the lower unit to the mid-section.
HTH..........ed
p.s. be sure you have both lower unit and remote control shifted to Neutral before you assemble (or whatever gear you prefer, just so both are the same).
