CONNECTING RODS AND PISTONS
and front-to-back measurements of t
he
cylinder.
Then, find the average
of
the measurements.
Bo
re
78.000-78.010
mm
(3.0709-3.0713
in)
Taper
limit
0.050
mm
(0.0020 in)
Out
of
round
limit
0.050
mm
(0.0020 In)
"C" = maximum
of
D
1
- D
6
Taper limit = maximum of D
1
or D
2
-
maxi-
mum of
Ds or Ds
Out
of
round limit = maximum of D
1
,
D3
or D
5
- minimum
of
D
2
,
D
4
or
D5
~
...
04
...
--
---
-
•
b. If out of specification, replace the cylinde
r,
and replace the piston a
nd
piston rings as a
set.
c. Measure piston
sk
irt diameter "
P"
with t
he
mi-
crometer.
a
Piston
Diameter
77.975-77.990
mm
(3.
0699-3
.0705 In)
p
a.
12.0 mm (0
.47
in
) from the bott
om
edge
of
the p
is
t
on
d. If out
of
speci
fi
cation, replace the piston and
piston rings as a se
t.
e. Calculate the piston-to-cylinder clearance
with the foll
ow
ing formula.
Piston-to-cylinder
cl
earance = Cylinder bore
"C" - Piston
sk
irt diameter "P"
Piston-to-cylinder clearance
0.010-0.035
mm
(0.0004-0.0014
in)
Limit
0.150
mm
(0.0059 in)
f. If out
of
spec
ifi
cation, replace the cylinder,
and replace the piston and piston rings as a
se
t.
......
,
,.
CHECKING THE PISTON RINGS
1. Measure:
• Piston ring si
de
clearance
Out of specification
-> Replace the piston
and piston rings as a set.
TIP
~~~~~~~~~~~~~~
Be
fo
re
measuring the piston ring side clearance,
eliminate any carbon deposits from the piston
ri
ng grooves and piston
ri
ngs .
Pis
to
n
ring
Top
ring
Ring side clearance
0.030-0.065
mm
(0.0012-0.0026
in)
Limit
0.115
mm
(0.0045 in)
2nd
ring
2. Insta
ll
:
Ring side clearance
0.020-0.055
mm
(0.0008-0.0022
in)
Limit
0.115
mm
(0.0045 in)
• Piston ring
(into the cylinder)
5-62
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