1976 Evinrude 40HP outboards Service Manual, Page 14Get this manual
TUNE-UP PROCEDURE When an owner brings motor to you for tune-up, or for some minor operating malfunction, the following procedure should be used as guide to determine the cause of the malfunctionWrite down the owner's commentsKeep an accurate card file on your service shop operationEach service operation should be on record as to the: OWNER'S NAME DATE MODEL NOSERIAL NONATURE OF COMPLAINT NATURE OF WORK PERFORMED COST TO THE OWNER WAS WORK PERFORMED UNDER WARRANTY After writing down the owner's comments, check the motor visually and begin systematic tune-up procedureConsult the Trouble Check Chart to find the causes of any malfunction which may be discovered when tuning up the motorSAFETY WARNING KEY SWITCH MUST BE IN OFF POSITION BEFORE ATTEMPTING ANY REPAIRS ON ENGINE EXCEPT WHERE OTHERWISE SPECIFIEDRemove intake by-pass covers, and cylinder headSlowly rotate flywheel and visually inspect pistons, rings, and cylinders for wear, freeness, and carbon depositsNOTE
Clean carbon from cylinder head and top of piStonsDo not alter piston deflectorSurface cylinder head and reinstall, using new gasketTighten cylinder head screws to specified torqueInspect spark plugsplace as necessaryClean and re-gap or re-