Hi Bob. The manual calls for 1/3 pint of oil to the gallon, 24/1, but I’d leave it at 16/1 for the sake of the motor. These motor have bushings and will last much longer with the extra oil. The water pump has two hard to find rubber impellers separated by a plate. There’s two NOS ones right now on Ebay. The flywheel gets torqued to 25 foot pounds. This was the first year for these motors to use modern seals and oil in the gearcase as they have a ball bearing on top of the pinion gear. If the NLA seals are worn, they can be replaced with new SKF seals. I’ve done this on a Sportsman and Sportwin with no signs of leakage yet. Here’s some diagrams of your motor:
