Johnson Evinrude Outboard Motors 1956-1970 1.5-40hp repair manual., Page 269Get this manual
SERVICE NO SHIFT CLEANING AND INSPECTING
Clean all water pump parts with solvent, and then dry them with compressed airInspect the water pump cover and base for cracks and distortion, possibly caused from overheatingInspect the face plate and water pump insert for grooves andor rough surfacesIf possible, AL WAYS install complete new water pump while the lower unit is disassembledA new impeller will ensure extended satisfactory service and give "peace of mind" to the ownerIf the old impeller must be returned to service, NEVER install it in reverse to the original direction of rotationInstallation in reverse will cause premature impeller failureInspect the impeller side seal surfaces and the ends of the impeller blades for cracks, tears, and wearCheck for glazed or melted appearance, caused from operating without sufficient waterIf any question exists, and as previously stated, install new impeller if at all possibleClean all parts with solvent and dry them with compressed airDISCARD all 0rings and gasketsInspect and replace the driveshaft if the splines are wornInspect