Generac Power Systems 941-2, 940-2 Section INTRODUCTION TO FUEL SYSTEM, Recommended Fuel, General

Section 3.1

INTRODUCTION TO FUEL SYSTEM

GENERAL

Recreational vehicle generators equipped with a gasoline fuel system are usually installed so that they share the fuel supply tank with the vehicle engine. When this is done, the generator Installer must never tee off the vehicle fuel supply line to deliver fuel to the generator.

When the generator fuel supply line is teed off the vehicle's fuel supply line, the more powerful vehicle engine's fuel pump will starve the generator when both are running. In addition, when the vehicle engine is not running the generator fuel pump will draw all of the gasoline from the vehicle engine line or even from the vehicle engine carburetor. This will result in hard starting of the vehicle engine.

One method of sharing the same fuel supply tank is to Install a special fitting at the tank outlet so that two fuel dip tubes can be fitted In the tank (Figure 1). Another method Is to install a new outlet In the tank. If the tank has an unused outlet, It can be used.

A second fuel dip tube can be installed in the original tank outlet if the tank outlet is large enough to accom- modate two dip tubes. The required fittings can be made at a machine shop. To install a second fuel out- let on the tank means removing the tank to braze or weld a new fitting into place.

DANGER! ATTEMPTING TO WELD OR BRAZE

!ON A FUEL TANK, EMPTY OR NOT, IS EXTREMELY DANGEROUS. FUEL VAPORS IN THE TANK WILL RESULT IN AN EXPLOSION.

The generator's fuel dip tube in the tank should be shorter than the vehicle engine's dip tube. This will prevent the generator from consuming the entire fuel supply.

DANGER! THE FUEL SYSTEM DESIGNED

!AND INSTALLED BY THE GENERATOR MAN- UFACTURER IS IN STRICT COMPLIANCE WITH STANDARDS ESTABLISHED BY THE RECREATIONAL VEHICLE INDUSTRY ASSO- CIATION (RVIA). NOTHING MUST BE DONE DURING MAINTENANCE THAT WILL RENDER THE SYSTEM IN NON-COMPLIANCE WITH THOSE STANDARDS.

DANGER! THERE MUST BE NO LEAKAGE OF

!GASOLINE OR GASOLINE VAPORS INTO THE VEHICLE. THE GENERATOR COMPARTMENT MUST BE VAPOR-TIGHT TO PREVENT ENTRY OF FUEL VAPORS OR FUMES INTO THE VEHICLE. THE GENERATOR'S VENTILA- TION SYSTEM MUST PROVIDE A FLOW OF AIR THAT WILL EXPEL ANY FUEL VAPOR ACCUMULATIONS.

RECOMMENDED FUEL

Use a high quality UNLEADED gasoline. Leaded REGULAR grade gasoline is an acceptable substi- tute.

Do NOT use any fuel containing alcohol, such as "gasohol". If gasoline containing alcohol is used, it must not contain more than 10% ethanol and it must be removed from the generator fuel system during storage. do NOT use fuel containing methanol. If any fuel containing alcohol Is used, the system must be inspected more frequently for leakage and other abnormalities.

Figure 1. Sharing a Fuel Supply Tank

EVAPORATION CONTROL SYSTEMS

Federal and state laws have imposed strict evapora- tive controls on gasoline fuel systems. The recreation- al vehicle industry has complied with such strict regu- lations by using specially designed fuel tanks, tank filler tubes and gas caps. Special canisters are often used to collect the gasoline vapors rather than let them escape into the atmosphere.

Such systems are designed to operate within very critical pressure ranges. For that reason, the vehicle manufacturer's fuel supply system design must not be

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