MBE4000 APPLICATION AND INSTALLATION
The fuel supply line must be above the bottom of the tank to ensure that dirt and sediments are not
drawn into the fuel system. Allow 5% clearance volume above the bottom of the tank.
The supply and return lines must be well supported within the tank. Cracks on the supply side
can cause the entrance of air and a subsequent loss of power. The supply and return lines must
be separated by at least 12 in. inside the tank to prevent mixing of hot return fuel with cold in
tank fuel.
The supply line should be at the center of the tank to compensate for angular operation (see
Figure 8-2).
Material
DDC does not approve the use of copper tubing because copper becomes brittle due to cold
working when subjected to vibration. Plastic lines must be made of a reinforced plastic suitable
for diesel fuel applications.
Flexible hosing must be resistant to fuel oil, lubricating oils, mildew, and abrasion, and must be
reinforced.
The lines must withstand a maximum suction of 17.7 in. Hg (600 mBar) without collapsing, a
pressure of 6.90 bar (100 psi) without bursting, and temperatures between -40°C (-40°F ) and
149°C (300°F).
Size
The fuel supply lines must be 10 mm ID or larger. The return lines must be 10 mm ID or larger.
The minimum nominal diameter must be 12 mm ID (0.5 in.) if the pipe lengths exceeds 6 m.
The restrictions imposed between the tank and fuel supply pump inlet determine the required
fuel supply line diameter.
The determinant of fuel line size is the restriction measured at the inlet of the engine. The
maximum allowable inlet restriction is 17.7 in. Hg (600 mBar) for all applications.
8.2.4
OPTIONAL DEVICES
The optional devices for the fuel system that may be used are a fuel cooler and a fuel water
separator.
Fuel Cooler
If the engine fuel inlet temperature exceeds 80°C (176°F) under anticipated operating conditions,
a fuel cooler is required.
Fuel Water Separator
A fuel water separator is required. The total fuel inlet system may not exceed the maximum
restriction of 10.29 in. Hg (350 mBar).
All information subject to change without notice.
(Rev. 03/06)
8-9
7SA250 0603
Copyright © 2006 DETROIT DIESEL CORPORATION