Mercury Optimax Models 135, 150, Direct Fuel Injection., Page 415Get this manual
LEFT HAND NON-RATCHETING
Water Pump
CLEANING AND INSPECTION
1Clean all water pump parts with solvent and dry with compressed air2Inspect water pump cover and base for cracks and distortion (from overheating)3Inspect face plate and water pump insert for grooves andor rough surfacesIMPORTANT: When completing gear housing repairs, that require removal of water pump impeller, it is recommended that the impeller be replacedIf it is necessary, however, to re-use impeller, DO NOT install in reverse to original rotation, or premature impeller failure will occur4Inspect impeller side seal surfaces and ends of impeller blades for cracks, tears and wearReplace impeller if any of these conditions are found5Inspect impeller bonding to impeller hub6Inspect impeller for glazed or melted appearance (caused by operation without sufficient water supply)Replace impeller if any of these conditions existIMPORTANT: It is recommended that all seals and gaskets be replaced (as normal repair procedure) to assure effective repair