Fuel Tank - GMC G/H Van Manual

G/H V
an
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• Use corrosion resistant steel tubing with short sections of approved electrically conductive hose to connect components. Steel
tube ends should be beaded for hose retention. Fuel supply is pressurized by an in-tank pump. Coupled hose or electrically
conductive quick-connect must be used.
All engines require a fuel return system which returns excess fuel from the injection pump and injector nozzles back to fuel tanks. Care
should be taken that these lines are not blocked nor their hoses pinched. The engine may run poorly or stall if these lines are restricted
or blocked.
All gasoline engine vehicles are equipped with fuel evaporative emission control equipment which is certified to be in compliance with
the Federal or applicable California Vehicle Emission Standards. Alterations to fuel tank and metering unit, lines, canister or canisters,
canister filters, canister purge control valves, relay switches, tank auxiliary vent valve, engine speed controller, or other devices/systems
are therefore not allowable since vehicle adherence to C.A.R.B. and Federal regulations may be affected.
Diesel powered vehicles incorporate water drain provisions in the fuel system. These valves are only to be opened when removing water
and contaminants from the fuel system.

Fuel Tank

The tank must have a minimum clearance of 2 in. top, front, rear and side to body and other supports.
Tank may be pressurized to 1.25 PSI maximum to check for final line leakage or for forcing fuel through the system. Pressures greater
than this amount may be detrimental and affect tank durability.
The use of auxiliary fuel tanks is not recommended. If an auxiliary fuel tank is added, the alterer must take responsibility for compliance
with affected motor vehicle safety and emission standards. Also, if an auxiliary fuel tank is added to a gasoline-powered vehicle, the fuel
must be drawn through a pipe at the top of the tank (balance line between tanks is not permitted). Venting of auxiliary tank to be provided
via purge canister and not to atmosphere. Gasoline fueled vehicles are now equipped with a fuel pump return line. If an auxiliary tank is
added, the tank selector valve must include a port which returns fuel to the tank from which the fuel is being drawn.
Similarly, addition of another fuel line for an auxiliary fuel user (such as a generator) will require emission revalidation.
In gasoline engines the fuel pump is located in the fuel tank. The battery must be disconnected before starting any work on the fuel system.
G/H Van 2007 – Rev. 2-07 G/H Van 2007 – Rev. 5-07
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