4 - 37
ENG
CYLINDER AND PISTON
CHECKING THE PISTON PIN
1. Check:
• piston pin
Blue discoloration/grooves
→
Replace, then
check the lubrication system.
2. Measure:
• piston pin-to-piston clearance
▼▼▼
▼
▼ ▼▼▼
▼
▼ ▼▼▼
▼
▼ ▼▼▼
▼
▼ ▼▼▼
▼
▼ ▼▼▼
▼
▼▼▼
a. Measure the piston pin outside diameter
a
.
If out of specification, replace the piston pin.
b. Measure the piston pin bore inside diameter
b
.
c. Calculate the piston pin-to-piston clearance
with the following formula.
d. If out of specification, replace the piston.
▲▲▲
▲
▲ ▲▲▲
▲
▲ ▲▲▲
▲
▲ ▲▲▲
▲
▲ ▲▲▲
▲
▲ ▲▲▲
▲
▲▲▲
INSTALLING THE PISTON
1. Install:
• piston rings
(onto the piston)
NOTE:
• Be sure to install the piston rings so that the
manufacturer’s marks or numbers are
located on the upper side of the rings.
• Lubricate the piston and piston rings liberally
with engine oil.
Piston pin outside diameter
21.991 ~ 22.000 mm
(0.8658 ~ 0.8661 in)
<Limit>: 21.971 mm (0.8650 in)
Piston pin bore inside diameter
22.004 ~ 22.015 mm
(0.8663 ~ 0.8667 in)
<Limit>: 22.045 mm (0.8679 in)
Piston pin-to-piston clearance =
Piston pin bore inside diameter
b
–
Piston pin outside diameter
a
Piston pin-to-piston clearance
0.004 ~ 0.024 mm
(0.00016 ~ 0.00094 in)
<Limit>: 0.074 mm (0.00291 in)
www.midwestmanuals.com