Volvo D16F Service Bulletin page 2

Volvo Trucks North America
Service Bulletin
Fuel System
When fault tracing, it is important to understand the function of the system in
order to avoid replacing non-defective components.
System Function
Fuel is drawn up the fuel lines by the supply pump (1)
through the pickup tube(s) in the fuel tank (2) in through
the Engine Electronic Control Unit (EECU) cooling plate
(3), and into the fuel filter housing (4). The fuel filter
housing can be equipped with a pre-filter (5) and a water
separator (6), where fuel is filtered through the primary
filter that separates any water from the fuel.
The supply pump (1) forces the fuel into the fuel filter
housing through the main filter (7) to a cylinder head
longitudinal fuel gallery (8). This channel supplies each
unit injector (9) with pressurized fuel by a circular groove
around each unit injector in the cylinder head. The
overflow valve (10) controls the fuel supply pressure to
the unit injectors.
The return fuel from the overflow valve (10) is returned
back to the fuel filter housing and is mixed with the fuel in
a channel within the fuel filter housing (4).
Design and Function
D
Date Group
230
11.2006
No. Page
247
2(11)
W2005904