RDG603A27
– Issue 6
Page 23 of 59
perfectly aligned. A maximum of 0.05mm (0.002”) misalignment in any plane is
acceptable. Ensure alignment is recheck after the first 4 hours of running, after the first
month and thereafter annually.
If the engine is out of alignment it will result in excessive vibration and possible damage
to the stern tube and propeller shaft.
Boats that are fitted with fully flexible drive couplings should still have the engine and
shaft alignment as close as possible. A dummy shaft may be required for this purpose.
Some types of flexible shaft couplings require the input and output to
be misaligned, check with the coupling manufacturer’s installation instructions.
Minimum clearance of 25mm between rails and engine beds.
7. Engine Inclination
The engine installation angle is the angle of the crankshaft centre to the water line
(
Figure 10
).
The propulsion efficiency decreases as the engine installation angle increases.
The
maximum
engine installation angle is 15°
Figure 10: Maximum Engine Installation Angle
Engine Installation Angle
Water Line
MAX 15°
