9.4.1 Any main propulsion diesel engine should
have torsional vibration and other vibrational characteristics acceptable
to the Administration. Precautions should be taken to ensure that
the engine is not operated within any speed range where excessive
vibration may be encountered.
9.4.2 Fuel injector pipes should be so positioned
or screened as to avoid fuel impingement on hot surfaces in the event
of leakage or fracture of the pipe. Where this is not practicable,
the Administration should consider the need to install double-walled
pipes and to ensure that any leakage is drained to a safe receptacle
fitted with an alarm to indicate that leakage is taking place. In
any case, unattended machinery spaces should have such an arrangement
installed.
9.4.3 Engines of a cylinder diameter of 200 millimetres
or a crankcase volume of 0.6 cubic metre and above should be provided
with crankcase explosion relief valves of an approved type with sufficient
relief area. The relief valves should be arranged with means to ensure
that discharge from them is directed so as to minimize the possibility
of injury to personnel.
9.4.4 The lubrication system and arrangements
should be efficient at all running speeds, due consideration being
given to the need to maintain suction and avoid the spillage of oil
in all conditions of list and trim and degree of motion of the craft.
9.4.5 Arrangements should be provided to ensure
that an alarm should be provided or that the engine should be stopped
or slowed to a safe speed in the event of the lubricating oil pressure
falling to a dangerously low level. Automatic shut-down of the engine
should only be activated by conditions which could lead to complete
breakdown-fire or explosion.
9.4.6 Where diesel engines are arranged to be
started, reversed or controlled by compressed air, the arrangement
of the air compressor, air receiver, and air starting system is to
be such as to minimize the risk of fire and explosion.
9.4.7 Arrangements should be provided to ensure
that, in the event of leakage in any liquid cooling system, ingress
of coolant liquid into the craft may be minimized. Such arrangements
should include measures to minimize the effect of such leakage upon
machinery serviced by the system.