Piston: Service and Repair

Fig. 5 Piston Installation Position:

Fig. 6 Cylinder Location & Tolerance Group Mark:

Fig. 7 Piston Tolerance Group Mark:

Install pistons to rods so that valve reliefs face outboard, Fig. 5. Install pistons into cylinders of same tolerance group, Figs. 6 and 7.
Pistons and piston pins are paired according to weight. Pistons are weighed with piston pins, piston rings and circlips. Piston pins must always remain in corresponding pistons and must not be interchanged within a set of pistons for one engine. If pistons and pins are interchanged, they must be rearranged by checking total weight. Weight of each piston assembly should be 25.3454-25.6278 ounces. Different tolerance groups could be used in the same engine.