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Cylinders, Pistons and Piston Rings Inspection
Cylinder
Visual inspection
Inspect cylinder walls for scratches, roughness or ridges
which indicate excessive wear. If cylinder bore is very
rough or deeply scratched, or ridged, rebore cylinder and
use over size piston.
Cylinder bore diameter, taper and out-of-round
Using a cylinder gauge (1), measure cylinder bore in
thrust and axial directions at two positions ("a" and "b")
as shown in the figure.
If any of the following conditions is noted, rebore
cylinder.
1) Cylinder bore dia. exceeds limit.
2) Difference of measurements at two positions
exceeds taper limit.
3) Difference between thrust and axial measurements
exceeds out-of-round limit.
Cylinder bore diameter
Standard: 78.00 – 78.014 mm (3.0709 – 3.0714 in.)
Limit: 78.114 mm (3.075 in.)
Cylinder taper and out-of-round
Limit: 0.10 mm (0.004 in.)
NOTE
If any one of four cylinders has to be rebored,
rebore all four to the same next oversize.
This is necessary for the sake of uniformity
and balance.
"a": 50 mm (1.96 in.)
S6JB0A1416031
I2RH0B140117-01
"b": 95 mm (3.74 in.)
Engine Mechanical: For M16A Engine with VVT 1D-45
Piston
Visual inspection
Inspect piston for faults, cracks or other damages.
Damaged or faulty piston should be replaced.
Piston diameter
As indicated in the figure, piston diameter should be
measured at a position 19.5 mm (0.77 in.) ("a") from
piston skirt end in the direction perpendicular to piston
pin.
Piston diameter specification
Standard size: 77.953 – 77.968 mm (3.0690 – 3.0696
in.)
Standard size (new one (with coating)): 77.969 –
77.984 mm (3.0696 – 3.0702 in.)
Oversize (0.50 mm (0.0196 in.)): 78.453 – 78.468 mm
(3.0887 – 3.0893 in.)
Piston clearance
Measure cylinder bore diameter and piston diameter to
find their difference which is piston clearance. Piston
clearance should be within specification as follows. If it is
out of specification, rebore cylinder and use oversize
piston.
NOTE
Cylinder bore diameters used here are
measured in thrust direction at two positions.
I2RH01140157-01
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