Propeller shaft systems
5
Shaft seals
There are different methods of lubrication for the
shaft seal. The two most common are water and
grease lubricated seals. Ensure easy access for
maintenance and inspection of the seal. Some seals
require a certain clearance to the gearbox coupling
in order to permit replacement of packing without dis-
connecting the shaft.
Water lubricated shaft seal
With water lubricated seal the water has two purpos-
es, lubricating and cooling the seal. Water could be
supplied to the water lubricated shaft seal in different
ways.
One way, which is suitable in displacement boats, is
to feed it from water pick up pipes in the stern tube.
The feed pipes should be designed to build up pres-
sure through the boats motion in water.
It is important to check that the water lubrication is
adequate, also at full speed, while test running a
new installation. Make sure that the pipes (
2) allow
enough water to flow in.
2
2
. Shaft seal
2. Water pick up pipes
Flexible propeller shaft
coupling
Together with a flexible mounted engine and a fixed
stuffing box, the propeller shaft must be fitted with a
flexible propeller shaft coupling. See combinations in
chapter
Selection of engine suspension
.
NOTE! The alignment of the engine is just as im-
portant with the above propeller equipment as for a
rigid shaft connection. The flexible stuffing box and
propeller shaft coupling are not designed to absorb a
constant angle deviation.
The flexible propeller shaft coupling could be fitted as
shown in the figure.
Summary of Contents for D11 series
Page 1: ...Marine Propulsion Diesel Engines Installation 1 1 D E D5 D16 series ...
Page 2: ......
Page 208: ...206 References to Service Bulletins Group No Date Concerns ...
Page 209: ...207 Notes ...
Page 210: ...208 Notes ...
Page 212: ...7748655 English 11 2007 ...