1978 Johnson 175, 200, 235 HP Outboard Service Manual, Page 85Get this manual
Before installing new piston rings, check gap between ends of ring by placing ring in its respective cylinder bore, then pushing ring down in the bore slightly with the bottom of the piston to square it upSee Figure 5-46Check for ring groove clearance with feeler gageSee Figures 5-47 and 5-48Corre ct gap and groove clearances are given in Section 2 63494
Figure 5-46Checking Ring Gap
Figure -4 7Checking Ring Groove Clearance
REASSEMBLY OF POWER HEAD
Proceed slowlyMake no forced assemblies unless press fits are called for and make no "dry" assembliesBe sure all parts to be assembled are clean and free from dirt and gritPerfectly good cylinder walls, pistons, and rings can be ruined in few minutes of operation unless all forms of grit are removed before assemblyWork in clean surroundings and with reasonably clean handsCoat all bearing surfaces, cylinder walls, etc with clean oil before assemblyWhere the use of "oil" is specified, we recommend OMC Outboard Lubricant