I just installed a 1976 {SN 4303053} Merc 1750 Balck Max on my 1991 Quantum when I tested this it seemed like the prop was slipping. Marked the prop and tested again the mark still lined up same problem. I can go aprox 5MPH forward or reverse I do notice when I powered up the throttle the **** tube is pushes more water making a better stream. When my RPMs go way up my boat goes slower. Before I installed this motor I replaced all the seals in the lower unit pulled the carrier replaced the inner and outer shaft seal and O-ring on the carrier I did take out the prop shaft to inspect the gears every thing looked ok. When I reinstalled I just made sure the point at the end of the shaft when into the hole.
When reinstalling the lower unit to get the shift shaft to stay in reverse I notice that I can turn the prop both ways and it will turn the crank shaft both ways when I turn The shift shaft to neutral position the prop spins free both ways when I turn The shift shaft to forward position the prop will not turn counter clockwise and turns free and makes a clicking sound if I turn clockwise. I think something?s not lined up in lower unit. Also if I turn the prop by hand the flywheel turns. With battery disconnected of course. I?m all ears.
When reinstalling the lower unit to get the shift shaft to stay in reverse I notice that I can turn the prop both ways and it will turn the crank shaft both ways when I turn The shift shaft to neutral position the prop spins free both ways when I turn The shift shaft to forward position the prop will not turn counter clockwise and turns free and makes a clicking sound if I turn clockwise. I think something?s not lined up in lower unit. Also if I turn the prop by hand the flywheel turns. With battery disconnected of course. I?m all ears.
