3.2. Inspection
3.2.1. Cylinder block
1) Clean the cylinder block thoroughly and make a visual inspection for cracks or damage.
2) Replace if cracked or severely damaged, and correct if slightly damaged.
3) Check oil and water flow lines for restriction or corrosion.
4) Make a hydraulic test to check for any cracks or air leaks.
(Hydraulic test) :
Stop up each outlet port of water/oil passages in the cylinder block, apply air pressure of
about 4kg/cm
2
against the inlet ports, then immerse the cylinder block in water for about 1
minute to check any leaks. (Water temperature: 70
C
)
3.2.2. Cylinder head
1) Check the cylinder head for cracks or damage.
(1) Carefully remove carbon from the lower face of the cylinder head using nonmetallic mate-
rial to prevent scratching of the valve seat faces.
(2) Check the entire cylinder head for very fine cracks or damage invisible to ordinary sight
using a hydraulic tester or a magnetic flaw detector.
2) Check the lower face of the cylinder
head for distortion.
(1)
Measure the amount of distortion
using a straight edge and a feeler
gauge at six positions as shown in
the figure right.
(2) If the measured value exceeds the
standard value(0.2mm), reface the
head with grinding paper of fine grain
size to correct such defect.
(3) If the measured value exceeds the
maximum allowable limit(0.3mm),
replace the cylinder head.
3) Measure flatness of the intake/exhaust
manifolds fitting surfaces on the cylinder
head using a straight edge and a feeler
gauge.
4) Hydraulic test method for the cylinder
head is the same as that for cylinder
block.
- 49 -
E
F
A
B
C
D
EQM3047I
<Figure 3-1> Measuring cylinder head
distortion
