Installation Manual
N40475 Chapter 7
Page 19
Fuel systems
Cleanliness of fuel system components
Cleanliness of the engine
NOTICE
It is important to maintain extreme cleanliness when working on the fuel system, since even tiny particles can
cause engine or fuel system problems.
Ensure the external surfaces of the engine are clean and dry before commencing work. Remove dirt and loose
debris before starting a repair on the fuel system. Ensure that no high pressure water is directed at the seals
for the injectors.
Environment
When possible, the service area should be positively pressurised with a clean air supply in order to ensure
that the components are not exposed to contamination from airborne dirt and debris. When a component is
removed from the system, the exposed fuel connections must be closed off immediately with suitable sealing
plugs. The sealing plugs should only be removed when the component is reconnected. The sealing plugs must
not be reused. Dispose of the sealing plugs immediately after use. Contact your nearest Perkins distributor in
order to obtain the correct sealing plugs.
New components
High pressure fuel lines are not reusable. New high pressure lines are manufactured for installation in one
position only. When a high pressure line is replaced, do not bend or distort the new line. Internal damage to the
pipe may cause metallic particles to be introduced to the fuel.
All new fuel lters, high pressure lines, tube assemblies and components are supplied with sealing plugs.
These sealing plugs should only be removed in order to install the new part. If the new component is not
supplied with sealing plugs then the component should not be used. The technician must wear suitable rubber
gloves. The rubber gloves should be disposed of immediately after completion of the repair in order to prevent
contamination of the system.
Refuelling
In order to refuel the diesel fuel tank, the refuelling pump and the fuel tank cap assembly must be clean and
free from dirt and debris. Only use fuel, free from contamination, that conforms to the specications in the
Users Handbook.
Design and assembly faults in the fuel system are responsible for many problems with marine diesel engines.
A good system is not hard to achieve, being largely a matter of avoiding obvious pitfalls.
Fuel connections
A common reason for service problems with fuel systems is the use of poor or incompatible connectors, where
the pressure tightness depends upon the use of sealing compounds, hose clamps, bre washers trapped
between inadequate and unmachined faces, or compression ttings which have been over-tightened to the
point where they no longer seal.
Cleanliness during initial assembly is also of vital importance, particularly when fuel tanks are installed, as
glass bres and other rubbish may enter tanks through uncovered apertures.