User Manual

CRANKCASE EM -57

PISTON

1. Check each piston to see whether it is damaged.

2. Check whether the piston pin (1) is installed correctly

in the piston hole.

If any defect is found, replace the piston and piston

pin as an assembly.

Piston pin should slide into the piston hole smoothly

when it is pushed by hand.

SUDEM7164L

3. Measure the clearance between piston pin and piston

hole by measuring the inner diameter of piston pin (1)

and piston boss.

Inner diameter of piston boss: 38mm

Outer diameter of piston pin: 38mm

Clearance Reference: 0.007~0.021mm

Clearance Limit: 0.05mm

SUDEM7165L

4. Measure the clearance between piston pin and con-

necting rod end.

Outer diameter of piston pin: 38mm

Inner diameter of connecting rod end: 38mm

Clearance Reference: 0.025~0.046mm

Clearance Limit: 0.1mm

SUDEM7166L

PISTON RING

1. Check the piston ring for any damage, unusual wear

or breakage. If damaged, replace the ring.

2. When replacing the piston, replace the piston pin to-

gether.

3. Measure the clearance between piston ring and the

wall of the ring groove, using a feeler gauge.

Piston ring

Standard

Limit

Ring No.1

0.106~0.170mm 0.2mm

Ring No.2

0.07~0.11mm 0.15mm

Oil ring

0.03~0.07mm 0.15mm

SUDEM7167L