1981 Johnson/Evinrude 4HP Outboards Service Manual, Page 47Get this manual
kIf necessary to remove pistons from connecting rod, remove wrist pin retaining rings, using Special Tool No325937See Figure 5-9Drive wrist pin through to free piston from connecting rod using Piston Cradle, Special Tool No326573 for SupportSee Figure 5-10 '_ 'NOTE
One side of piston is marked "L" (Loose) on insideWhen wrist pin is to be removed, "L" side of piston must be down and driving tool must be applied to tight endBe careful not to distort pistonSee Figure 5-11
1Loose mark
Figure 5-11"L" Mark on Piston
CLEANING, INSPECTION, AND REPAIR
CYLINDER BLOCK AND CRANKCASE Check cylinder walls for excessive wear and check cylinder ports for carbon accumulationCylinder walls wear in various degrees depending on lubrication and conditions under which the motor is operated Major portion of wear is in the port area and the area covered by ring travelCheck cylinder for size and wall straightness by using an inside micrometer or dial bore indicatorRefer to Section for specified dimensionsIf wear is greater than 0.002" (0.05 mm), replace cylinder block or rebore block for oversize pistonsPiston and ring sets are available 0.030" (0.76 mm) oversize