US

INTRODUCTION
Thank you for purchasing this model of the Guardian
product line by Generac Power Systems Inc. This
model is a compact, high performance, air-cooled,
engine-driven generator designed to automatically
supply electrical power to operate critical loads dur-
ing a utility power failure.
This unit is factory installed in an all-weather, metal
enclosure that is intended exclusively for outdoor instal-
lation. This generator will operate using either vapor
withdrawn liquid propane (LP) or natural gas (NG).
READ THIS MANUAL THOROUGHLY
If any portion of this manual is not understood, contact
the nearest Authorized Dealer for starting, operating
and servicing procedures.
Throughout this publication, and on tags and decals
affixed to the generator, DANGER, WARNING,
CAUTION and NOTE blocks are used to alert person-
nel to special instructions about a particular opera-
tion that may be hazardous if performed incorrectly
or carelessly. Observe them carefully. Their defini-
tions are as follows:
DANGER
After this heading, read instructions that, if not
strictly complied with, will result in serious person-
al injury, including death, in addition to property
damage.
After this heading, read instructions that, if not
strictly complied with, may result in serious person-
al injury or property damage.
After this heading, read instructions that, if not
strictly complied with, could result in damage to
equipment and/or property.
NOTE:
After this heading, read explanatory statements
that require special emphasis.
These safety warnings cannot eliminate the haz-
ards that they indicate. Common sense and strict
compliance with the special instructions while
performing the service are essential to preventing
accidents.
Four commonly used safety symbols accompany the
DANGER, WARNING and CAUTION blocks. The type
of information each indicates follows: This symbol points out important safety infor-
mation that, if not followed, could endanger
personal safety and/or property of others. This symbol points out potential explosion haz-
ard. This symbol points out potential fire hazard.

This symbol points out potential electrical shock
hazard.
The operator is responsible for proper and safe use
of the equipment. The manufacturer strongly recom-
mends that the operator read this Owner's Manual
and thoroughly understand all instructions before
using this equipment. The manufacturer also strong-
ly recommends instructing other users to properly
start and operate the unit. This prepares them if they
need to operate the equipment in an emergency.
CONTENTS
This manual contains pertinent owners information,
including warranty, electrical diagrams, exploded
views and lists of repair parts, for three different
models:
04389-3 6 kW NG, 7 kW LP, single-cylinder GH-
410 Engine
04456-3 12 kW NG, 12 kW LP, V-twin GT-990
Engine
04390-3 13 kW NG, 15 kW LP, V-twin GT-990
Engine
OPERATION AND MAINTENANCE
It is the operator's responsibility to perform all safety
checks, to make sure that all maintenance for safe
operation is performed promptly, and to have the
equipment checked periodically by an Authorized
Dealer. Normal maintenance service and replacement
of parts are the responsibility of the owner/operator
and, as such, are not considered defects in materials
or workmanship within the terms of the warranty.
Individual operating habits and usage contribute to
the need for maintenance service.
Proper maintenance and care of the generator ensures
a minimum number of problems and keep operating
expenses at a minimum. See an Authorized Dealer
for service aids and accessories.
HOW TO OBTAIN SERVICE
When the generator requires servicing or repairs,
contact an Authorized Dealer for assistance. Service
technicians are factory-trained and are capable of
handling all service needs.
When contacting an Authorized Dealer about parts
and service, always supply the complete model num-
ber and serial number of the unit as given on its data
decal, which is located on the generator. See Figure 1.1
or Figure 1.2 in Section 1.6 for decal location.
Model No. ____________ Serial No. ______________
AUTHORIZED
DEALER LOCATION
To locate the nearest GUARDIAN AUTHORIZED
DEALER, please call this number:
1-800-333-1322
DEALER LOCATION INFORMATION
CAN BE OBTAINED AT THIS NUMBER or visit
www.guardiangenerators.com. Table of Contents
Air-cooled 7 kW, 12 kW and 15 kW Generators


1
Introduction ........................Inside Front Cover
Read This Manual Thoroughly ........................ IFC
Contents
.......................................................... IFC
Operation and Maintenance ............................ IFC
How to Obtain Service ..................................... IFC
Authorized Dealer Locator Number ................... IFC
Safety Rules ........................................................2
Standards
Index
.................................................. 3
Section 1 General Information ...................4
1.1 Unpacking/Inspection
.................................... 4
1.2 Protection
Systems
........................................ 4
1.3
NEC Requirement for Arc Fault Circuit
Interruption Breaker for Bedrooms .............. 4
1.4 The
Generator
............................................... 5
1.5 Specifications
................................................ 6
1.6 System
Set
LED
............................................ 7
1.7 Fuel Requirements and Recommendations ... 7
1.8 Fuel
Consumption
......................................... 7
1.9 Reconfiguring the Fuel System ...................... 7
1.10 Location ........................................................ 8
1.11 Battery Installation ........................................ 9
1.12 The Battery ................................................... 9
Section 2 Post Installation Start-up
and Adjustments .......................10
2.1 Before
Initial
Startup................................... 10
2.2 Check Transfer Switch Operation ............... 10
2.3 Electrical
Checks
........................................ 10
2.4 Generator Tests Under Load ....................... 11
2.5 Checking
Automatic
Operation
.................... 11
2.6
Adjusting the Regulator
(Natural Gas Only) ....................................... 12
2.7 Engine
Governor
Adjustment
...................... 13
2.8 Voltage Regulator Adjustment ...................... 14
Section 3 Operation ....................................14
3.1 Break-in
Procedure
..................................... 14
3.2 Using the Auto/Off/Manual Switch ............... 14
3.3 Automatic Transfer Operation ..................... 15
3.4 Sequence of Automatic Operation ............... 15
3.5 Manual
Transfer
Operation
......................... 16
3.6 Setting the Exercise Timer .......................... 17
3.7 Protection
Systems
...................................... 17
Section 4 Maintenance ...............................18
4.1 Fuses
........................................................... 18
4.2 Checking the Engine Oil Level ..................... 18
4.3 Changing the Engine Oil .............................. 19
4.4 Changing the Oil Filter ................................ 19
4.5 Changing the Engine Air Cleaner ................. 19
4.6 Spark
Plug(s)
.............................................. 20
4.7 Battery
Maintenance
.................................... 20
4.8
Adjusting GH-410/GT-990/760
Valve Clearance ............................................ 21
4.9 Cooling
System
........................................... 21
4.10 Attention After Submersion
......................... 22
4.11 Corrosion Protection ................................... 22
4.12 Out of Service Procedure ............................. 22
4.13 Service Schedule ......................................... 23
Section 5 Troubleshooting ........................ 24
5.1 Troubleshooting
Guide
................................ 24
Section 6 Notes ........................................... 25
Section 7 Electrical Data ........................... 28
Section 8 Exploded Views and
Parts Lists ................................... 42
Section 9 Mounting Dimensions ............. 63
Section 10 Warranty ................................... 64 2
Study these SAFETY RULES carefully before install-
ing, operating or servicing this equipment. Become
familiar with this Owners Manual and with the
unit. The generator can operate safely, efficiently and
reliably only if it is properly installed, operated and
maintained. Many accidents are caused by failing to
follow simple and fundamental rules or precautions.
The manufacturer cannot anticipate every possible
circumstance that might involve a hazard. The warn-
ings in this manual, and on tags and decals affixed
to the unit are, therefore, not all-inclusive. If using
a procedure, work method or operating technique
the manufacturer does not specifically recommend,
ensure that it is safe for others. Also make sure the
procedure, work method or operating technique uti-
lized does not render the generator unsafe.
DANGER Despite the safe design of this generator,
operating this equipment imprudently, neglecting
its maintenance or being careless can cause
possible injury or death. Permit only responsible
and capable persons to operate or maintain this
equipment. Potentially lethal voltages are generated by
these machines. Ensure all steps are taken to
render the machine safe before attempting to
work on the generator. Par