Mercury Mariner 4, 5 102CC Sail 1990 Outboard Service Shop Manual, Page 100Get this manual
Propeller Shaft 1Replace propeller shaft if any of the following conditions exist:
(a) Splines are twi sted or worn
Cam Follower
1Replace cam follower if end of follower shows signs of wear
(b) Oil seal su rfaces are deeply groovedallowi ng water to enter gear housing (c) Slid ing clutch slot worn (dPropel ler nut threads stripped, damaged excessive ly worn
Water Pump Componen-ts
1Rep lace water pump component if worngrooved or if components show evidence of over heat or ot her damage2 1343
2C heck propeller shaft fo strai ghtness Place shaft on either balance wheels or "V" blocks and rotate shaft while observing spline area for bend (wobb le)Replace shaft (if bent)