Parts Inspection And Measurement - Yanmar 3TNV Series Service Manual

4.4.5 Parts inspection and measurement

(1) Cylinder block
Especially clean head surface, cylinder bores and oil
holes, and check after removing any carbon deposit
and bonding agent.
(a) Appearance inspection
Check if there is any discoloration or crack. If crack
is suspected, perform color check. Sufficiently clean
the oil holes and check they are not clogged.
(b) Cylinder bore and distortion
Measure at 20 mm below the crest of the liner, at 20
mm from the bottom end and at the center.
Roundness:
Roundness is found as follows though it is the
simple method. Measure cylinder diameters of the
A direction and the B direction on each section of a,
b and c.
Roundness is the maximum value among those
difference values.
Cylindricity:
Cylindricity is found as follows though it is the
simple method.
Measure cylinder diameters of a, b and c sections
in the A direction, and calculate the difference in
maximum value and minimum value of the
measured diameters.
In the same way measure and calculate the
difference in the B direction.
Cylindricity is the maximum value between those
difference values.
Item
Cylinder inside diameter
Roundness
Cylinder bore
Cylindricity
4. Disassembly, Inspection and Reassembly of Engines
Model Standard
3TNV82A 82.000 82.030
TNV84 84.000 84.030
TNV88 88.000 88.030
4TNV94L 94.000 94.030
4TNV98 98.000 98.030
4TNV106(T) 106.000 106.030
all TNV 0.01 or less
95
mm
Limit
82.200
84.200
88.200
94.130
98.130
106.130
0.03