1978 Johnson 175, 200, 235 HP Outboard Service Manual, Page 17Get this manual
OPERATION (SECOND HOUR): Bring boat into planing attitude and reduce power to 4000 rpm or threequarter throttle (approximate) while maintaining planing attitudeAt intervals during the second hour, apply full power for periods of one to two minutesreturning throttle to original setting (4000 rpm threequarter throttle) for cooling periodAvoid continuous full throttle operation for extended periods during the next eight hours be in off position before attempting any repairs on engine except where otherwise specified
1Remove exhaust covers and cylinder he adsSlowly rotate flywheel and visually inspect pistons, rings, and cylinders for wear, freeness, and carbon depOSitsSee Section 5
Uffim!11NOTE i
Piston ring condition should be determined before continuing tune-upGum and varnish depOSits on rings or pistons may be removed with an application of OMC Accessory Engine CleanerIf pistons and rings are considered to be in