Sidekick JSS 4D Hard Top 2WD L4-1.8L (1997)
Piston: Description and Operation
The piston is cast aluminum alloy, and has two compression rings (top and 2nd rings), and one oil ring. The outer surface of the top ring is treated with
nitriding for improvement in abrasion resistance. The oil ring consists of two rails and one spacer. The piston pin is offset 1.0 mm towards the major
thrust side. This allow a gradual change in thrust pressure against the cylinder wall as the piston travels its path. Pins, made of chromium steel, have a
floating fit in the pistons and connecting rods. The connecting rods are made of forged steel, and the rod bearings are of precision insert type.