1980 Johnson 4HP Service Manual, Page 59Get this manual
Before installing new piston rings, check gap placing ring in its between ends 01 ring respective cylinder then pushing ring down in the slightly with the bottom 01 the piston to square it upSee Figure 5-15Check ring groove clearance with 1eeler gageSee Figure 5-16Correct gap and groove clearances given in Section 2 1ectly good cylinder walls, pistons, and rings ruined in 1ew minutes 01 operation unless all forms of grit removed before assembIyWork in clean surroundings and with reasonabIy clean handsCoat all bearing surfaces, cylinder walls, etc with clean oil fore assembIyWhen the use "oil" is specified, we recommend 50:1 outboard lubricant
Aways use new gaskets throughout when reassembIing the powerheadGasket Sealing pound lighty to both sides cylinder head gasket and to outer diameter cranksha(t sea00 not use sealer i( so stated the gasket