Cylinder Block - Yanmar 4JH2E Service Manual

Chapter 2 Basic Engine
_1_._c_y_h_n_d_e_r_B_l_oc_k~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-- 4 JH Series
1. Cylinder Block
The cylinder block is a thin-skinned, (low-weight). short
skirt type with rationally placed ribs. The side walls are
wave shaped to maximize ridigity for strength and low
noise.
1·1 Inspection of parts
Make a visual Inspection to check for cracks on engines
that have frozen up, overturned or otherwise been subject·
ed to undue stress. Perform a color check on any portions
that appear to be cracked, and replace the cylinder block if
the crack Is not repairable.
1 ·2 Cleaning of oil holes
Clean all oil holes, making sure that none are clogged up
and the blind plugs do not come off.
Color check kit
Part code No. 97550·004560
Printed in Japan
AOAJ029-9002
Quantity
Penetrant
1
Developer 2
Cleaner 3
2-1
1-3 Color check procedure
(1) Clean the area to be Inspected.
(2) Color check kit
The color check test kit consists ol an aerosol cleaner,
penetranl and developer.
(3) Clean the area to be Inspected with the cleaner.
Either spray the cleaner on directly and wipe, or wipe
the area with a cloth moistened with cleaner.
(4) Spray on red penetrant
Alter cleaning, spray on the red penetrant and allow
5
~
10 minutes for penetration. Spray on more red
penetrant if ii dries before It has been able to penetrate.
(5) Spray on developer
Remove any residual penetrant on the surface alter the
penetranl has penetrated, and spray on the developer.
If there are any cracks In the surface, red dots or a red
line will appear several minutes after the developer
dries.
Hold the developer 300
~
400mm (11.8110
~
15.7480in.)
away from the area being Inspected when spraying,
making sure to coal the surface uniformly.
(6) Clean the surface with the cleaner.
NOTE: Without fail, read the Instructions for the color
check kit before use.