Guardian Technologies 004270-3 User Manual

Page of 68
28 Generac
®
Power Systems, Inc.
Because diesel fuels are less volatile than gasoline or
gaseous fuels, they are considered safer from the
standpoint of storage and handling. As a result,
installers may tend to be careless in their installation
practices, which can result in poor engine perfor-
mance. For example, a poorly tightened fuel line may
not show any signs of leakage; however, air can be
drawn into the loose connection and cause problems.
Air that is trapped in the diesel fuel system results in
hard starting and rough engine operation.
Dirt that enters the fuel system also may cause prob-
lems. Lines and piping must be properly installed
and tightened to prevent dirt from entering. Diesel
fuel must be kept clean.
Factory-installed generator fuel system components
include (a) a fuel filter, (b) a 12-volt DC electric pump,
(c) an injection pump, and (d) interconnecting lines
and fittings. Connect a fuel supply line to the supply
fitting and a return line from the fuel return fitting
back to the tank. 
NOTE:
Fuel supply and return fittings located on the gen-
erator are 1/8” NPT. 
Use a length of approved flexible fuel hose between
the fuel connection fittings and rigid fuel lines (see
Sections 2.4.2 and 2.4.3).
2.4.1 FUEL TANK
Either the generator must share the vehicle’s engine
fuel tank, or a separate fuel tank for the generator set
must be installed. All fuel tanks installed on the vehi-
cle must be constructed, installed, and restrained so
they comply with applicable codes, standards, and
regulations.
If the generator is to share the vehicle’s engine tank,
separate fuel pickup tubes are required for the engine
and the generator. Generac recommends that the fuel
pickup tube be two to three inches (51 to 76 mm)
shorter than the vehicle’s engine pickup tube. This
prevents the generator from depleting the entire fuel
supply during prolonged generator operating peri-
ods.
Do NOT tee the generator fuel supply line into
the vehicle engine fuel supply line. If this is
done, the generator will be starved of fuel
when both engines are operating at the same
time. Also, while the vehicle engine is not run-
ning, generator operation may drain the vehi-
cle engine supply line, making it difficult to
start the vehicle engine.
2.4.2 GENERATOR FUEL SUPPLY LINES
2.4.2.1 Rigid Fuel Lines
Those lines used to supply fuel from a tank to the
generator must comply with applicable codes, stan-
dards, and regulations. The following general rules
apply to rigid fuel lines:
• Rigid lines should be of annealed, seamless, drawn
aluminum, or steel.
• Lines and fittings must comply with SAE J512F,
“Standard Automotive Fittings,” or with ANSI
B126.26 (latest edition).
• Route the fuel line so that at least 2 inches (51 mm)
of clearance is maintained between the line and
any exhaust system parts.
• Do not attach electrical wiring to fuel lines. Route
the wiring so it cannot come into contact with any
fuel line.
• Route fuel lines so that, if they leak, fuel does not
drip onto any electrical or exhaust system parts.
• Use nonferrous metal straps without sharp edges
to secure fuel lines.
• Fuel system components must be accessible, but
protected from abrasion, chafing, road damage,
and kinking.
2.4.2.2 Flexible Fuel Line
Use a length of approved flexible fuel hose between
the generator fuel supply fitting and rigid fuel lines.
This prevents breaking of the line caused by vibra-
tion, shifting, settling, or movement. The following
rules apply:
• The flexible hose must comply with SAE J30B,
“Standard for Fuel and Oil Hose.” It must be
approved for use with diesel fuel.
• The hose should be at least 6 inches (152 mm)
longer than is needed, to prevent the hose from
rupturing if the generator shifts or settles.
2.4.3 GENERATOR FUEL RETURN LINES
The same general rules that apply to fuel supply lines
also apply to fuel return lines.
NOTE:
Locate the diesel fuel return line at least 12 inch-
es from the tank fuel pickup tubes to prevent air
bubbles from entering the fuel supply lines.
!
Section 2 – Installation
QUIETPACT™ 75D Recreational Vehicle Generator