Mazda 121 - Piston, Piston Ring, and Piston Pin

INSPECTION /
REPAIR
o -
R|NG
GnoovE
lo.7m
in)
OIAMETER
PISTON. PISTON
RING,
AND
PTSTON
PIN
Plston
Caution
.
lf the
piston
is
reptaced,
the
piston rings
must also
be
replaced.
1.
Inspect the outer
circumferences
of all
pistons
for seizure
or scoring.
Replace
the
piston
f
necessary
2.
Measureihe outer
diameter
of each
piston
at a right angle
(90o)
to the
piston
p
n,
16.5mm
(0'650 in) below the
oil
ring land
lower edge.
Piston diameter
mm
{in)
3. Measure the
piston{o-cylinder
clearance
Clearance:
0.039-0,052mm
(0.0015-0.0020
in)
Maximum:
0.15mm
(0.006 in)
4. lf the clearance
exceeds
the maximum,
replace the
piston
or rebore
the cylinders
to
fit oversize
pistons
FING
Pision and
Piston
Rings
1 . Iveasure
the
piston
ring to
ring land
clearance
around the
enlire circumference
usrng
a new
plslon
nng.
Clearance
(Top
and Second)
B3
0.030-0.070
(0.0012-0
0028)
015
{0.006)
lf the clearance
exceeds
the
maximum,
replace the
piston.
Inspect
the
piston
rings
for damage,
abnormal
wear, and
breakage.
Replace
the
piston
rings
ii necessary
4. Insert tlie
piston
ring into the
cylinder by
hand
and use the
Diston to oush
it to
the bottom
of the
ring travel
2.
3.
7 0.961
-7
0.967
\2.7937
2.7939)
0.25
(0.010)
ove6ze
7 1.21
1 7 1.217
I2.AO36-2.aO2A)
0.50
(0.020)
oversze
71.461
71.467
12
A134-2.8137)
0.75
(0.030)
oversrze
7 t .711-71
.717
Q.A2$-2.A235)
]00
(0
04)
oversize
71.961-7r.967
(2.8331 2.8333)
B-56