Generac GP1800, GP3250, GP5000, GP5500, GP6500 Service Manual
...
®
Diagnostic
RepaiR
Manual
GP Series Portable Generators
MODELS:
GP1800
GP3250
GP5000
GP5500
GP6500
GP7000
GP8000
PORTABLE GENERATORS
Throughout this publication, “DANGER!” and “CAUTION!” blocks are used to alert the mechanic to special
instructions concerning a particular service or operation that might be hazardous if performed incorrectly or
carelessly. PAY CLOSE ATTENTION TO THEM.
DANGER! UNDER THIS HEADING WILL BE FOUND SPECIAL INSTRUCTIONS WHICH, IF NOT COMPLIED
WITH, COULD RESULT IN PERSONAL INJURY OR DEATH.
*
CAUTION! Under this heading will be found special instructions which, if not complied with, could result
in damage to equipment and/or property.
*
These “Safety Alerts” alone cannot eliminate the hazards that they signal. Strict compliance with these special
instructions plus “common sense” are major accident prevention measures.
SAFETY
NOTICE TO USERS OF THIS MANUAL
This SERVICE MANUAL has been written and published by Generac to aid our dealers' mechanics and company service personnel when servicing the products described herein.
It is assumed that these personnel are familiar with the servicing procedures for these products, or like or
similar products manufactured and marketed by Generac. That they have been trained in the recommended
servicing procedures for these products, including the use of common hand tools and any special Generac
tools or tools from other suppliers.
Generac could not possibly know of and advise the service trade of all conceivable procedures by which a
service might be performed and of the possible hazards and/or results of each method. We have not undertaken any such wide evaluation. Therefore, anyone who uses a procedure or tool not recommended by
Generac must first satisfy themselves that neither his nor the products safety will be endangered by the service procedure selected.
All information, illustrations and specifications in this manual are based on the latest product information
available at the time of publication.
When working on these products, remember that the electrical system and engine ignition system are capable of violent and damaging short circuits or severe electrical shocks. If you intend to perform work where
electrical terminals could be grounded or touched, the battery cables should be disconnected at the battery.
Any time the intake or exhaust openings of the engine are exposed during service, they should be covered to
prevent accidental entry of foreign material. Entry of such materials will result in extensive damage when the
engine Is started.
During any maintenance procedure, replacement fasteners must have the same measurements and
strength as the fasteners that were removed. Metric bolts and nuts have numbers that indicate their strength.
Customary bolts use radial lines to indicate strength while most customary nuts do not have strength markings. Mismatched or incorrect fasteners can cause damage, malfunction and possible injury.
REPLACEMENT PARTS
Components on Generac recreational vehicle generators are designed and manufactured to comply with
Recreational Vehicle Industry Association (RVIA) Rules and Regulations to minimize the risk of fire or explosion. The use of replacement parts that are not in compliance with such Rules and Regulations could result
in a fire or explosion hazard. When servicing this equipment, it is extremely important that all components be
properly installed and tightened. If improperly installed and tightened, sparks could ignite fuel vapors from fuel
system leaks.
Specifications .......................................................... 2
Part 1 – General Information .................................. 9
Section 1.1 – Generator Fundamentals ................ 10
Magnetism .......................................................10
Electromagnetic Fields.....................................10
Electromagnetic Induction................................10
A Simple AC Generator ...................................11
A More Sophisticated AC Generator ................11
Section 1.2 – Measuring Electricity ....................... 13
Meters ............................................................13
The VOM ..........................................................13
Measuring AC Voltage .....................................13
Measuring DC Voltage .....................................13
Measuring AC Frequency ................................13
Measuring Current ...........................................14
Measuring Resistance .....................................14
Electrical Units .................................................15
Ohm's Law .......................................................15
Section 1.3 – Brushless, Capacitor
Excitation System ............................ 16
Introduction ......................................................16
Stator Assembly ...............................................16
Rotor Assembly ................................................16
Circuit Breakers ...............................................16
Operation .........................................................17
Section 1.4 – Brushed Excitation System ............. 18
Introduction ......................................................18
Stator Assembly ...............................................18
Brush Holder and Brushes ...............................18
Rotor Residual Magnetism...............................18
Voltage Regulator ............................................18
Operation .........................................................18
Section 1.5 – Testing, Cleaning and Drying .......... 20
Insulation Resistance .......................................20
The Megohmmeter...........................................20
Stator Insulation Resistance Test .....................20
Cleaning the Generator ....................................21
Drying the Generator .......................................21
Part 2 – AC Generators ......................................... 21
Section 2.1 – Brushless Capacitor
Troubleshooting Flowcharts ............. 22
Section 2.2 – Brushed Excitation
Troubleshooting Flowcharts ............. 24
Section 2.3 – AC Diagnostic Tests ........................ 26
Introduction ......................................................26
Test 1 – Check No-Load Voltage
and Frequency ....................................26
Test 2 – Check Circuit Breaker.........................26
Test 3 – Check Continuity of
Receptacle Panel ................................26
Test 4 – Field Flash Alternator
(Configuration “A” Only) .......................27
Test 5 – Check Brushed Rotor Circuit ..............28
Test 6 – Check Capacitor .................................29
Test 7 – Test Brushless DPE Winding ..............30
Test 8 – Test Brushless Stator Windings ..........30
Test 9 – Test Brushed Stator Windings ............31
Test 10 – Check Load Voltage & Frequency ....31
Test 11 – Check Load Watts & Amperage .......31
Test 12 – Adjust Voltage Regulator ..................31
Part 3 – Engine Troubleshooting .......................... 33
Section 3.1 – 389/206/163cc Troubleshooting
Flowcharts ....................................... 34
Section 3.2 – 410cc Troubleshooting Flowcharts .. 37
Section 3.3 – Diagnostic Tests .............................. 42
Test 20 – Check 1.5 Amp Fuse ........................42
Test 21 – Check Battery & Cables ...................42
Test 22 – Check Voltage at
Starter Contactor (SC) ........................42
Test 23 – Check Start-Run-Stop Switch ..........42
Test 24 – Test OFF-ON Switch .........................43
Test 25 – Check Starter Motor .........................43
Test 25 – Check Ignition Spark ........................45
Test 26 – Check Spark Plugs ...........................46
Test 29 – Check Carburetion ...........................46
Test 30 – Choke Test ........................................47
Test 33 – Check Valve Adjustment ...................47
Test 36 – Check Engine / Cylinder Leak Down
Test / Compression Test ......................48
Test 38 – Check Flywheel ................................48
Test 39 – Remove Wire 18 / Shutdown Lead ...49
Test 40 – Check / Adjust Governor
(389cc Engine) ....................................49
Test 41 – Check / Adjust Governor
(410cc Engine) ....................................50
Test 45 – Check Oil Level Switch .....................51
Test 46 – Check Oil Pressure Switch ...............51
Test 49 – Test Recoil Function .........................52
Test 50 – Test Engine Function ........................52
Part 4 – Disassembly ............................................. 53
Section 4.1 – Major Disassembly .......................... 54
Part 5 – Electrical Data .......................................... 71
Electrical Schematic, GP1850 .............................. 72
Electrical Schematic, GP3250 .............................. 73
Electrical Schematic, GP5000/5500/GP6500 ....... 74
Wiring Diagram, GP5000/5500/GP6500 ............... 75
Electrical Schematic, GP7000E/GP8000E ........... 76
Wiring Diagram, GP7000E/GP8000E ................... 77
Electrical Formulas ............................................... 78
Page 1
AH
M
SPECIFICATIONS – GP1800
Outlets
A
Circuit Breakers
M
Other Features
H
(2) 5-20R 120V
(1) 20A
On/Off Switch
Product Series GP1800
A/C Rated Output Watts: 1800
A/C Maximum Output Watts: 2050
A/C Voltage 120VAC
A/C Frequency 60 Hz
Rated 120 VAC Amperage 7.5
Max 120 VAC Amperage 8.5
Engine Displacement 163cc
Engine Type OHV
Engine RPM 3600
Recommended Oil 5W30
Lubrication Method Splash Sump
Choke Type Manual Lever
Fuel Shut Off Manual Lever
Idle Control Full Speed
Starting Method Manual
Battery n/a
Battery Size n/a
Low Oil Shutdown Method Low Level
Start Switch Type On/Off Toggle
Switch Location Control Panel
Single-Point Lifting Eye N/A
Fuel Gauge Built-In
Fuel Tank Capacity (Gal) 4
Fuel Tank Capacity (Liters) 15.14
Run Time at 50% (Hours) 14
Cord Set No
Handle Style Folding
Wheel type n/a
Length (L) 23.5
Width (W) 17
Height (H) 17.5
Extended Length (EL) 23.5
Unit Weight (lbs) 79
Spark Plug Type NGK BPR4ES
or Champion
RN14YC
Spark Plug Gap 0.028"-0.031"
(0.7-0.8mm)
Oil Capacity 0.634 quart
(0.6 liter)
Page 2
H
A
M
Product Series GP3250
A/C Rated Output Watts: 3250
A/C Maximum Output Watts: 3750
A/C Voltage 120VAC
A/C Frequency 60 Hz
Rated 120 VAC Amperage 13.5
Max 120 VAC Amperage 15.6
Engine Displacement 206cc
Engine Type OHV
Engine RPM 3600
Recommended Oil 5W30
Lubrication Method Splash Sump
Choke Type Manual Lever
Fuel Shut Off Manual Lever
Idle Control Full Speed
Starting Method Manual
Battery n/a
Battery Size n/a
Low Oil Shutdown Method Low Level
Start Switch Type On/Off Toggle
Switch Location Control Panel
Single-Point Lifting Eye N/A
Fuel Gauge Built-In
Fuel Tank Capacity (Gal) 4
Fuel Tank Capacity (Liters) 15.14
Run Time at 50% (Hours) 13.5
Cord Set No
Handle Style Folding
Wheel type 7.0" Solid Wheels
Length (L) 25.5
Width (W) 21
Height (H) 19
Extended Length (EL) 39.5
Unit Weight (lbs) 91
Spark Plug Type NGK BPR4ES
or Champion
RN14YC
Spark Plug Gap 0.028"-0.031"
(0.7-0.8mm)
Oil Capacity 0.634 quart
(0.6 liter)
SPECIFICATIONS – GP3250
Outlets
A
Circuit Breakers
M
Other Features
H
(4) 5-20R 120V
(2) 20A
On/Off Switch
Page 3
H
B
N
M
A
SPECIFICATIONS – GP5000
Receptacles
A
B
Circuit Breakers
M
N
Other Features
H
(4) 5-20R 120V
L14-30R Twist-Lock 120/240V
(2) 20A
(2) 25A
Hour Meter with
Maintenance Reset
Product Series GP5000
A/C Rated Output Watts: 5000
A/C Maximum Output Watts: 6250
A/C Voltage 120/240VAC
A/C Frequency 60 Hz
Rated 120/240 VAC Amperage 20.8
Max 120/240 VAC Amperage 26.0
Engine Displacement 389cc
Engine Type OHV
Engine RPM 3600
Recommended Oil 5W30
Lubrication Method Splash Sump
Choke Type Manual Lever
Fuel Shut Off Manual Lever
Idle Control Full Speed
Starting Method Manual
Battery n/a
Battery Size n/a
Low Oil Shutdown Method Low Level
Start Switch Type 3-Position
Switch Location On Engine
Single-Point Lifting Eye N/A
Fuel Gauge Built-In
Fuel Tank Capacity (Gal) 6.6
Fuel Tank Capacity (Liters) 24.981
Run Time at 50% (Hours) 10
Cord Set No
Handle Style Folding Interlocked
Wheel type 9.5" Solid Wheels
Length (L) 33.5
Width (W) 26.5
Height (H) 27.5
Extended Length (EL) 47
Unit Weight (lbs) 167
Spark Plug Type NHSP F7RTC or
Champion RN9YC
Spark Plug Gap 0.028"-0.031"
(0.7-0.8mm)
Oil Capacity 1.16 quart
(1.1 liter)
Page 4
H
B
N
M
A
Product Series GP5500
A/C Rated Output Watts: 5000
A/C Maximum Output Watts: 6875
A/C Voltage 120/240VAC
A/C Frequency 60 Hz
Rated 120/240 VAC Amperage 22.9
Max 120/240 VAC Amperage 28.6
Engine Displacement 389cc
Engine Type OHV
Engine RPM 3600
Recommended Oil 5W30
Lubrication Method Splash Sump
Choke Type Manual Lever
Fuel Shut Off Manual Lever
Idle Control Full Speed
Starting Method Manual
Battery n/a
Battery Size n/a
Low Oil Shutdown Method Low Level
Start Switch Type 3-Position
Switch Location On Engine
Single-Point Lifting Eye N/A
Fuel Gauge Built-In
Fuel Tank Capacity (Gal) 6.6
Fuel Tank Capacity (Liters) 24.98
Run Time at 50% (Hours) 10
Cord Set No
Handle Style Folding Interlocked
Wheel type 9.5" Solid Wheels
Length (L) 33.5
Width (W) 26.5
Height (H) 27.5
Extended Length (EL) 47
Unit Weight (lbs) 167
Spark Plug Type NHSP F7RTC or
Champion RN9YC
Spark Plug Gap 0.028"-0.031"
Oil Capacity 1.16 quart
(0.7-0.8mm)
(1.1 liter)
SPECIFICATIONS – GP5500
Receptacles
A
B
Circuit Breakers
M
N
Other Features
H
(4) 5-20R 120V
L14-30R Twist-Lock 120/240V
(2) 20A
(2) 25A
Hour Meter with
Maintenance Reset
Page 5
H
B
N
M
A
SPECIFICATIONS – GP6500
Outlets
A
B
Circuit Breakers
M
N
Other Features
H
Hour Meter with Maintenance Reset
(4) 5-20R 120V
L14-30R Twist-Lock 120/240V
(2) 20A
(2) 30A
Product Series GP6500
A/C Rated Output Watts: 6500
A/C Maximum Output Watts: 8000
A/C Voltage 120/240VAC
A/C Frequency 60 Hz
Rated 120/240 VAC Amperage 27.1
Max 120/240 VAC Amperage 33.3
Engine Displacement 389cc
Engine Type OHV
Engine RPM 3600
Recommended Oil 5W30
Lubrication Method Splash Sump
Choke Type Manual Lever
Fuel Shut Off Manual Lever
Idle Control Full Speed
Starting Method Manual
Battery n/a
Battery Size n/a
Low Oil Shutdown Method Low Level
Start Switch Type 3-Position
Switch Location On Engine
Single-Point Lifting Eye N/A
Fuel Gauge Built-In
Fuel Tank Capacity (Gal) 6.6
Fuel Tank Capacity (Liters) 24.98
Run Time at 50% (Hours) 9
Cord Set No
Handle Style Folding Interlocked
Wheel type 9.5" Solid Wheels
Length (L) 33.5
Width (W) 26.5
Height (H) 27.5
Extended Length (EL) 47
Unit Weight (lbs) 172
Spark Plug Type NHSP F7RTC or
Champion RN9YC
Spark Plug Gap 0.028"-0.031"
(0.7-0.8mm)
Oil Capacity 1.16 quart
(1.1 liter)
Page 6
H
B
N
M
A
Product Series GP7000
A/C Rated Output Watts: 7000
A/C Maximum Output Watts: 8750
A/C Voltage 120/240VAC
A/C Frequency 60 Hz
Rated 120/240 VAC Amperage 29.2
Max 120/240 VAC Amperage 36.5
Engine Displacement 410cc
Engine Type OHVI
Engine RPM 3600
Recommended Oil 5W30
Lubrication Method Full Pressure
Choke Type Manual Lever
Fuel Shut Off Manual Lever
Idle Control Full Speed
Starting Method GP7000 Manual
Starting Method GP7000E Manual or Electric
Battery Size (if equipped) 12VDC 10 Ahr
Low Oil Shutdown Method Low Pressure
Start Switch Type 3-Position
Switch Location On Engine
Single-Point Lifting Eye N/A
Fuel Gauge Built-In
Fuel Tank Capacity (Gal) 8
Fuel Tank Capacity (Liters) 30.28
Run Time at 50% (Hours) 11
Cord Set No
Handle Style Folding Interlocked
Wheel type 9.5" Solid Wheels
Spark Plug Type Champion RC14YC
Spark Plug Gap 0.030" (0.76mm)
Oil Capacity 1.5 quart w/filter
SPECIFICATIONS – GP7000/GP7000E
Outlets
A
B
Circuit Breakers
M
N
Other Features
H
Hour Meter with Maintenance Reset
(4) 5-20R 120V
L14-30R Twist-Lock 120/240V
(2) 20A
(2) 30A
Page 7
Loading...