1971 Evinrude 40HP outboards Service Manual, Page 60Get this manual
gCheck water intake screen and passages by removing by-pass coverhInspect clutch dog, drive gears, pinion gear, and thrust washers for wearReplace if wornIf shifter dog and drive gear engagement surfaces are chipped or excessively rounded off, this may indicate improper shifting by operator of motor, or incorrect adjustment of remote controlsiWash bearings in clean solvent such as Solvasol and dry with cumpressed airReplace if worn or pitted423 4
Figure 6-13Removing Shift Rod Bushing Inspect driveshaft splines for wearReplace shaft if worn NOTE bent exhaust tube may cause upper driveshaft splines to wear excessively, and also damage crankshaft splinesdInspect gearcase and exhaust housing for nicks on the machined surfacesRemove nicks and re-surface faces on surface plateStart with No120 emery and finish with No180Check parallelism on plate with surface gage and scriberSee Figure 6-15A drill press table will also serve, using the spindle as gageDo not attempt to straighten, replace if benteInspect water tube for obstructions or kinks which may restrict water flowFigure 6-15Checking Parallelism