Yanmar 3JH4E Service Manual page 123

3) After fitting the piston ring, make sure it moves
easily and smoothly.
4) Stagger the piston rings at 120° intervals, making
sure none of them line up with the piston.
1st piston ring
2nd piston ring
5) The oil ring is provided with a coil expander. The
coil expander joint should be opposite (staggered
180°) the oil ring gap.
5. Inspection and Servicing of Basic Engine Parts
Direction of
piston pin
Oil ring
107
120
2st piston ring
120
Gap
1st piston ring
2st piston ring
Oil ring
1st piston ring
120
Oil ring
Joint of coil
expander