ENGINE
Inspecting the Cylinder Block and Components
12/05
6LY3 Service Manual
5-49
© 2007 Yanmar Marine International
Measuring the Camshaft Bearings
Measure the outside diameter of the camshaft
bearing with a micrometer.
The bearing oil clearance is calculated by
subtracting the measured camshaft outside
diameter from the inside diameter of the camshaft
bearing. The camshaft bearing at the water pump
end is measured with a cylinder gauge, after it is
installed in the block. Replace if they exceed the
stated limits or are damaged in any way.
Inspecting the Camshaft for Straightness
• Support both ends of the camshaft on V-blocks.
• Place a dial indicator at the central bearing area
(Figure 5-67, (1))
and rotate the camshaft on the
V-blocks.
Figure 5-67
Figure 5-67
1 – Central Bearing
• Measure for variations.
• Replace camshaft if it measures beyond the
stated limits.
NOTICE: The reading on the dial
indicator is divided by two to determine the
camshaft bend.
Intake Cam Height
Standard
Limit
49.435-49.565 mm
(1.9462-1.9513 in.)
49.185 mm
(1.9364 in.)
Exhaust Cam Height
Standard
Limit
48.135-48.265 mm
(1.8950-1.9001 in.)
48.110 mm
(1.9334 in.)
Cam Shaft Bearing Specifications
Item
Standard
Limit
Bushing ID
56.980-57.050 mm
(2.2433-2.2460 in.)
57.130 mm
(2.2452 in.)
Camshaft OD
56.910-59.940 mm
(2.2405-2.3598 in.)
56.880 mm
(2.2393 in.)
Oil Clearance
0.040-0.140 mm
(0.0015-0.0055 in.)
0.250 mm
(0.0098 in.)
Camshaft Bend Limit
0.02 mm (0.0007 in.)
0005652
(1)
