Note

Measure cylinder bore "C" by taking side-to-side and front-to-back measurements of the cylinder. Then, find the average of the measurements.

Cylinder bore "C"

65.50 - 65.51 mm (2.5787 - 2.5791 in)

Wear limit

65.56 mm (2.5811 in)

Taper limit "T"

0.05 mm (0.002 in)

Out of round "R"

0.05 mm (0.002 in)

"C" =

maximum of D1 - D6

"T" =

maximum of D1 or D2 - maximum

of D5 or D6

"R" =

maximum of D1 D3 or D5 -

minimum of D2 D4 or D6

b. If out of specification, replace the cylinder, and the pistons and piston rings as a set.

c. Measure piston skirt diameter "P" with the micrometer.

@ 4 mm (0.16 in) from the bottom edge of the piston b. If out of specification, replace the cylinder, and the pistons and piston rings as a set.

c. Measure piston skirt diameter "P" with the micrometer.

@ 4 mm (0.16 in) from the bottom edge of the piston

Piston size "P"

d. If out of specification, replace the piston and piston rings as a set.

e. Calculate the piston-to-cylinder clearance with the following formula.

Piston-to-cylinder clearance = Cylinder bore "C" -Piston skirt diameter "P"

Piston-to-cylinder clearance 0.010 - 0.035 mm (0.0004 - 0.0014 in) <Limit>: 0.055 mm (0.0022 in)

f. If out of specification, replace the cylinder, and the piston and piston rings as a set.

EAS00263

CHECKING THE PISTON RINGS

1. Measure: • piston ring side clearance Out of specification ^ Replace the piston and piston rings as a set.

NOTE:

Before measuring the piston ring side clearance, eliminate any carbon deposits from the piston ring grooves and piston rings.

Piston ring side clearance Top ring

0.030 - 0.065 mm (0.0012 - 0.0026 in) <Limit>: 0.115 mm (0.0045 in) 2nd ring

0.030 - 0.065 mm (0.0012 - 0.0026 in) <Limit>: 0.125 mm (0.0049 in)

2. Install: • piston ring (into the cylinder)

NOTE:

Level the piston ring into the cylinder with the piston crown.

@5 mm (0.20 in) 3. Measure: • piston ring end gap Out of specification ring.

NOTE:

Replace the piston

The oil ring expander spacer's end gap cannot be measured. If the oil ring rail's gap is excessive, replace all three piston rings.

Piston ring end gap Top ring

0.25 - 0.35 mm (0.0098 - 0.0138 in) <Limit>: 0.60 mm (0.0236 in) 2nd ring

0.7 - 0.8 mm (0.0276 - 0.0315 in) <Limit>: 1.15 mm (0.0453 in) Oil ring

CHECKING THE PISTON PINS

The following procedure applies to all of the piston pins. 1. Check: • piston pin

Blue discoloration/grooves ^ Replace the piston pin and then check the lubrication system.

2. Measure: • piston pin outside diameter @ Out of specification ^ Replace the piston pin.

Piston pin outside diameter 15.991 - 16.000 mm (0.6296 - 0.6299 in) <Limit>: 15.971 mm (0.6288 in)

Piston pin outside diameter 15.991 - 16.000 mm (0.6296 - 0.6299 in) <Limit>: 15.971 mm (0.6288 in)

Measure:

►piston pin bore inside diameter ® Out of specification ^ Replace the piston.

Piston pin bore inside diameter 16.002 - 16.013 mm (0.6300 - 0.6304 in) <Limit>: 16.043 mm (0.6316 in)

Piston pin bore inside diameter 16.002 - 16.013 mm (0.6300 - 0.6304 in) <Limit>: 16.043 mm (0.6316 in)

4. Calculate: • piston-pin-to-piston clearance Out of specification ^ Replace the piston pin and piston as a set.

Piston-pin-to-piston clearance = Piston pin bore size -Piston pin outside diameter Piston-pin-to-piston clearance 0.002 - 0.022 mm (0.0001 - 0.0009 in) <Limit>: 0.072 mm (0.0028 in)

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