1985 OMC 65, 100 and 155 HP Models Commercial Service Manual, PN 507450-D, Page 212Get this manual
5 Examine the water deflectors
in the cylinder water
passagesThe water deflectors direct water circulationReplace
the deflectors if deterioratedUse the correct replacement part number as specified in the parts catalogFailure to use the proper replacment part could result in engine damage through overheating6Remove the screws from the outer exhaust coverRemove the outer and inner exhaust covers and discard the gaskets