1971 Evinrude StarFlite 100 HP Outboards Service Manual, PN 4753, Page 56Get this manual
PISTON RINGS Install the piston rings on each pistonSpread each ring with ring expander just enough to slip it over the head of the piston and down into placeBe sure the rings fit freely in the piston ring groovesThe ring grooves are pinned to secure the position of the rings, primarily to prevent ends of the rings from catching on the edges of the ports in the cylinders, but also to assure staggering of the ring gapsPISTON-CONNECTING ROD INSTALLATION Coat pistons and cylinder bores with oil and install piston-connecting rod assemblies, being sure to match each assembly with the cylinder it was removed fromThe intake side of the piston deflector must be placed toward the intake portThe use of automotive type ring compressing tools should be avoided, as these frequently cause damaged pistons and broken piston rings through imperfect alignment of the ring gap and piston dowel pinThe use of Special Tool (for standard size rings and pistons only) is recommendedSee Special Tool CatalogUSing one hand to push the piston into the cylinder, use the free hand to guide the connecting rod into place and to align the rod with respect to the crankshaftSee Figure 5-31CRANKSHAFT AND SEAL RINGS Seal rings must be fitted to the six crankshaft grooves with minimum side clearance of .0015" or maximum of .0025"See Figure 5-32This clearance range works best with the amount of oil being drawn through the engine, since it is ultimately the oil film left adhering to these parts during the process of fuel induction that completes the seal between the four connecting rod cavities