6
Generac
®
Power Systems, Inc.
1.8.2 GENERATOR AND LOAD COMPATIBILITY
The generator must be fully compatible with the rated
voltage, number of phases and frequency of the con-
nected electrical loads. The generator, connected elec-
trical devices, or both, can be damaged if voltage, num-
ber of phases and frequency are not compatible.
NOTE:
This manual assumes that the standby generator has
been properly selected, installed and interconnected
by a competent, qualified electrician or installation
contractor. Once the installation is complete, do
nothing that may result in noncompatibility between
the generator and connected electrical loads.
1.8.3 ENGINE
Make ............................................................General Motors
Displacement ......................................4.3 liters (262 cu. in.)
Cylinder Arrangement ......................................................V-6
Valve Arrangement ......................................Overhead Valves
Firing Order ........................................................1-6-5-4-3-2
Number of Main Bearings....................................................4
Compression Ratio ....................................................9.4-to-1
No. of Teeth on Flywheel..................................................168
Ignition System ......................................................Electronic
Ignition Timing at 1,800 rpm ....................40 degrees BTDC
Rated Horsepower at 1,800 rpm ......................................67
Spark Plug Gap ....................................0.045 inch (1.1 mm)
Recommended Spark Plugs ............AC 41-932 or equivalent
Oil Pressure ............................................................30-50 psi
Crankcase Oil Capacity ....................4.5 U.S. quarts (4.25 L)
Recommended Engine Oil..................................SAE 15W-40
Type of Cooling System ............Pressurized, closed recovery
Cooling Fan ........................................................Pusher Type
Cooling System Capacity ....................4.5 U.S. gallons (17 L)
Recommended Coolant ........................Use a 50-50 mixture of
ethylene glycol and soft water.
Fuel Consumption
Natural Gas ..............................................................720 cfh
LP Gas ..........................................................288 cfh/7.9gph
1.9 FUEL
REQUIREMENTS
AND RECOMMENDATIONS
With LP gas, use only the vapor withdrawal system.
This
type of system uses the vapors formed above the liquid
fuel in the storage tank.
Recommended fuels should have a Btu content of at
least 1,000 Btus per cubic foot for natural gas; or at
least 2,520 Btus per cubic foot for LP gas. Ask your fuel
supplier for the Btu content of your fuel.
Fuel pressure for both natural gas and liquid propane
setups should be 11 inches to 14 inches of water column
(0.6 psi) at all load ranges.
Gaseous fuels such as natural gas and liquid
propane (LP) gas are highly explosive. Even the
slightest spark can ignite such fuels and cause an
explosion. No leakage of fuel is permitted. Natural
gas, which is lighter than air, tends to collect in
high areas; LP gas is heavier than air and tends to
settle in low areas – install leak detectors accord-
ingly.
1.9.1 CONVERSION TO LP GAS VAPOR
The generator is shipped from the factory configured for
using natural gas as fuel. To convert the fuel system to LP
gas, proceed as follows (Figure 1.3).
1. Remove end cap from the pressure reducer valve.
2. Turn the tension screw counterclockwise until all ten-
sion is removed from the inner spring.
3. Install and tighten the end cap.
4. Invert the pressure reducer valve. In other words, turn
it upside down (end cap facing downward).
5. Purge and leak test the entire fuel system according to
gaseous fuel codes. NO LEAKS can appear at any point
in the system.
Figure 1.3 – Conversion to LP Gas Vapor
Section 1 — General Information
Guardian Liquid-cooled 40 kW Generator
