SERIES IMPACT 36 PLUS
Models 940-2
SERVICE MANUAL
P. O. Box 297 Whitewater, WI
NOTICE TO USERS OF THIS MANUAL
SAFETY
REPLACEMENT PARTS
TROUBLESHOOTING
SERVICE MANUAL
TABLE OF CONTENTS
SPECIFICATIONS & CHARTS
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COMPUTER CONTROLLED VARIABLE SPEED RV GENERATORS
COMPONENTS TESTING
PART GENERAL INFORMATION
Series Impact 36 Plus
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ELECTROMAGNETIC FIELDS
Section GENERATOR FUNDAMENTALS
MAGNETISM
ELECTROMAGNETIC INDUCTION
Figure 4. Operation of a Simple Generator
ALTERNATING CURRENT
ELECTRICAL UNITS
Figure 5. Alternating Current Sine Wave
Figure 6. Electrical Units
OHMS LAW
REACTANCE IN AC CIRCUITS
AMPERES = VOLTSOHMS
Section GENERATOR FUNDAMENTALS
Figure 10. Block Diagram of the Impact 36 Plus System
Figure 9. Capacitive Reactance
CAPACITIVE REACTANCE
WHY VARIABLE SPEED CONTROL?
Section GENERATOR FUNDAMENTALS
Section GENERATOR FUNDAMENTALS
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Section MAJOR GENERATOR COMPONENTS
UPPER FAN HOUSING
Figure 2 Permanent Magnet Rotor Assembly
INTRODUCTION
STATOR RETAINING RING
STATOR ASSEMBLY
ROTOR HUB
STEPPER MOTOR
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Figure 5. Schematic- Stator Windings
Section MAJOR GENERATOR COMPONENTS
Section MAJOR GENERATOR COMPONENTS
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GENERAL
Figure 1. Block Diagram- A Generator System
Section OPERATIONAL ANALYSIS
OPERATIONAL DESCRIPTION
OPERATIONAL DESCRIPTION CONTINUED
Section OPERATIONAL ANALYSIS
DIRT AND MOISTURE
CAUTION! When using a Megohmmeter or
Section INSULATION RESISTANCE
INSULATION RESISTANCE TESTERS
TEST FOR SHORTS BETWEEN WINDINGS
CLEANING THE GENERATOR
TEST ALL STATOR WINDINGS TO GROUND
RESULTS OF TESTS
DANGER! DO NOT WORK WITH SOLVENTS
Figure 3. Schematic - Stator Windings
DRYING THE GENERATOR
CAUTION! Some generators use epoxy or
Section INSULATION RESISTANCE
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STATOR ASSEMBLY
Section COMPONENTS TESTING
Figure 1. Stator Leads
INTRODUCTION
Section COMPONENTS TESTING
STATOR ASSEMBLY CONTINUED
Figure 2. Schematic- Stator Windings
Figure 4. Battery Charge Circuit
TESTING THE BATTERY CHARGE CIRCUIT
Figure 3. Battery Charge Windings and Rectifier
Section COMPONENTS TESTING
Section COMPONENTS TESTING
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COMPONENTS
Section CONTROL PANEL
CONSTRUCTION
Figure 1. Exploded View of Control Panel
Section CONTROL PANEL
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GENERAL
Section SHEET METAL
Impact Plus Generator
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EXPLODED VIEW OF SHEET METAL GASOLINE UNITS
Section SHEET METAL
TO CARBURETOR
DESCRIPTION
PARTS LIST FOR SHEET METAL GASOLINE UNITS
Section SHEET METAL
DESCRIPTION
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EXPLODED VIEW OF SHEET METAL LP UNITS
Section SHEET METAL
DESCRIPTION
PARTS LIST FOR SHEET METAL GASOLINE UNITS
Section SHEET METAL
DESCRIPTION
Section SHEET METAL
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2.1 GENERAL INFORMATION 2.2 VALVE TRAIN
2.3 PISTON, RINGS, CONNECTING ROD 2.4 CRANKSHAFT & CAMSHAFT
PART ENGINE MECHANICAL
COMPUTER CONTROLLED VARIABLE SPEED RV GENERATORS
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4-CYCLE ENGINE THEORY
Figure 3. Power Stroke Figure 4. Exhaust Stroke
Section GENERAL INFORMATION
Figure 1. Intake Stroke Figure 2. Compression Stroke
NOTE DO NOT USE GASOLINE CONTAINING METHANOL
RECOMMENDED FUELS
RECOMMENDED ENGINE OIL
NOTE DO NOT MIX OIL WITH THE GASOLINE
ENGINE TUNE-UP
THE UNIT IS NOW READY FOR SERVICE
STORAGE INSTRUCTIONS
Section GENERAL INFORMATION
EXPLODED VIEW OF ENGINE LONG BLOCK
NOTE 1- Item 36 Includes valve seats and guides
Section GENERAL INFORMATION
DESCRIPTION
VALVE COMPONENTS REMOVAL
Section VALVE TRAIN
VALVE TRAIN COMPONENTS
Figure 1. Valve Train Components
Figure 4. Cylinder Head Removal
VALVE SERVICE
DANGER! ALWAYS WEAR SAFETY GLASSES WHEN REMOVING THE VALVE SPRINGS
Figure 5. Removal of Valve Spring
Figure 8. Valve Guides
VALVE COMPONENTS INSTALLATION
Figure 11. Installation of Intake and Exhaust Valves
Figure 10. Valve Tappet
Figure 12. Installing Valve Spring Washers
VALVE COMPONENTS INSTALLATION CONTINUED
ADJUSTING VALVE CLEARANCE
Figure 14. Install Rocker Arm & Pivot Ball stud
Figure 18. Rocker Arm Cover Installation
ROCKER ARM COVER INSTALLATION
Figure 16. Adjusting Valve Clearance
Figure 17. Tightening Pivot Ball Jam Nut
Section VALVE TRAIN
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OVERSIZE PISTON & RINGS
Section PISTON, RINGS, CONNECTING ROD
Figure 1. Piston, Rings and Connecting Rod
PRIOR TO REMOVAL
Figure 5. Piston Major Diameter
PISTON RINGS
Figure 4. Piston Minor Diameter
Figure 6. Ring to Groove Side Clearance
Figure 9. Connecting Rod
CONNECTING ROD
ASSEMBLY AND INSTALLATION
Figure 7. Ring Locations in Piston Grooves
Section PISTON, RINGS, CONNECTING ROD
CYLINDER SERVICE
Figure 10. Match Marks on Rod and Cap
CAMSHAFT REMOVAL
Section CRANKSHAFT AND CAMSHAFT
CRANKCASE COVER REMOVAL
CRANKSHAFT REMOVAL
Figure 4. Points to Check on Camshaft
CAMSHAFT INSPECTION
CRANKSHAFT INSPECTION
Figure 5. Points to Check on Crankshaft
COMPRESSION RELEASE MECHANISM
INSTALLING THE CRANKSHAFT
INSTALLING THE CAMSHAFT
Figure 6. Bearing Bore in Crankcase Cover
Section CRANKSHAFT AND CAMSHAFT
Figure 9. Timing Mark on Crankshaft Gear
Figure 10. Alignment of Timing Marks
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INTRODUCTION TO FUEL SYSTEM
AIR CLEANER & AIR INTAKE
PART GASOLINE FUEL SYSTEM
FILTER & FUEL PUMP
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EVAPORATION CONTROL SYSTEMS
Section INTRODUCTION TO FUEL SYSTEM
RECOMMENDED FUEL
DANGER! ATTEMPTING TO WELD OR BRAZE
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Figure 2. Typical Gasoline Fuel System
Section INTRODUCTION TO FUEL SYSTEM
Figure 1. Engine Air Cleaner
Section AIR CLEANER AND INTAKE
AIR CLEANER
AIR INTAKE
Section AIR CLEANER AND INTAKE
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FUEL PUMP
Section FUEL FILTER AND FUEL PUMP
FUEL FILTER
Figure 1. Fuel Filter Typical
Section FUEL FILTER AND FUEL PUMP
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DESCRIPTION
Section CARBURETOR
GENERAL INFORMATION
CARBURETOR OPERATION
Figure 3. Carburetor Exploded View
CARBURETOR DISASSEMBLY
CLEANING AND INSPECTION
Section CARBURETOR
Figure 5. Adjusting Throttle Linkage
ADJUSTMENT
THROTTLE LINKAGE ADJUSTMENT
ENGINE SPEED
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Figure 6. Carburetor Removal
Section CARBURETOR
Section AUTOMATIC CHOKE
OPERATIONAL CHECK AND ADJUSTMENT
Figure 2. Choke Adjustment
OPERATION
Section AUTOMATIC CHOKE
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A6060 CIRCUIT BOARD
STEPPER MOTOR PROBLEMS
Section SPEED CONTROL SYSTEM
Figure 1. Speed Control System
Section SPEED CONTROL SYSTEM
TESTING THE STEPPER MOTOR
Figure 2. The Stepper Motor Connector Figure 3. The Stepper Motor
4.1 INTRODUCTION TO FUEL SYSTEM 4.2 SHUTOFF VALVE & REGULATOR
Air Cleaner & Air Intake Section Speed Control System Section
PART GASEOUS FUEL SYSTEM
4.3 CARBURETOR
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VAPOR WITHDRAWAL
ADVANTAGES OF GASEOUS FUELS
FUEL SYSTEM COMPONENTS
IMPORTANT CONSIDERATIONS
IMPORTANT CONSIDERATIONS CONTINUED
FUEL SUPPLY LINES
EXCESS FLOW VALVE
Figure 1. A Typical LP Gas Fuel System
GASEOUS CARBURETION
LEAKAGE TESTING
Figure 2. Gas Carburetion Diagram
DANGER! DO NOT USE FLAME TO CHECK
Section INTRODUCTION TO FUEL SYSTEM
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DANGER! DO NOT ATTEMPT TO ADJUST
ADJUSTMENTS
TESTING THE FUEL LOCKOFF SOLENOID
Section SHUTOFF VALVE AND REGULATOR
Section SHUTOFF VALVE AND REGULATOR
If battery voltage is Indicated but the solenoid does NOT ener
If battery voltage is NOT Indicated, a problem exists In the DC
RESULTS OF TEST
CARBURETION
CARBURETOR ADJUSTMENT
DISASSEMBLY AND REASSEMBLY
Figure 1. LP Gas Carburetor
Section CARBURETOR
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COMPUTER CONTROLLED VARIABLE SPEED RV GENERATORS
PART ENGINE OIL COOLING SYSTEM
5.1 ENGINE OIL SYSTEM 5.2 ENGINE COOLING SYSTEM
Series Impact 36 Plus
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INTRODUCTION TO OIL SYSTEM
Figure 1. Oil System Diagram
Section ENGINE OIL SYSTEM
OIL PUMP
CRANKSHAFT OIL SEALS
BREATHER ASSEMBLY
OIL PUMP CONTINUED
PRESSURE RELIEF VALVE
OIL FILTER SUPPORT
Figure 6. Breather Assembly
OIL SUMP
Figure 7. Oil Filter Support
Section ENGINE OIL SYSTEM
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COOLING AIR INLET OPENINGS
Section ENGINE COOLING SYSTEM
GENERATOR AIR FLOW
Figure 1 - Air Flow Through Engine-Generator
COMPENSATING FOR RESTRICTIONS
TESTING THE INSTALLATION
CAUTION Do not install the inverter in the
INVERTER LOCATION
ENGINE DC CONTROL SYSTEM
ENGINE SHUTDOWN FEATURES
PART ENGINE ELECTRICAL SYSTEM
A6060 CIRCUIT BOARD
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GENERAL
Figure 1. Schematic- Engine DC Control System
Section ENGINE DC CONTROL SYSTEM
CHOKE and Section 6.2, A6060 CIRCUIT
HOW IT WORKS
NOTE Also see Section 3.5, AUTOMATIC
BOARD
NOTE 1 - See SHUTDOWN FEATURES” In Section 6.5 Page
WIRE
battery is connected
Section 6.2 A6060 CIRCUIT BOARD
Section A6060 CIRCUIT BOARD
CIRCUIT BOARD CONNECTIONS CONTINUED
Section ENGINE CRANKING SYSTEM
BATTERY
Figure 1. Schematic - Cranking Circuit
CABLE LENGTH
STARTER CONTACTOR
BATTERY CONTINUED
START-RUN-STOP SWITCH SW1
Section ENGINE CRANKING SYSTEM
Figure 4. Starter Motor
STARTER MOTOR
Figure 3. Starter Contactor
Section ENGINE CRANKING SYSTEM
Section ENGINE CRANKING SYSTEM
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Figure 3. Ignition Sensor Schematic
IGNITION CAGE ASSEMBLY
Figure 1. Ignition Cage Assembly
Section ENGINE IGNITION SYSTEM
Figure 6. Setting Spark Plug Gap
TESTING THE SYSTEM
Figure 7. Ignition System Diagram
IGNITION MODULE CONTINUED
spark. Personal injury or damage to equip- ment may result
Figure 8. Testing for Spark
Warning! Do NOT use a screwdriver to test for
Figure 9. Checking Engine Miss
Figure 13. Testing Ignition Coil Figure 14. Testing Ignition Module
TESTING THE SYSTEM CONTINUED
Figure 12. Testing Ignition Sensor
Note Only one spark should be observed upon initial cranking
OIL TEMPERATURE SWITCH
Section SHUTDOWN FEATURES
OIL PRESSURE SWITCH
Figure 3. Testing the Oil Temperature Switch
ADDITIONAL SHUTDOWN FEATURES
Section SHUTDOWN FEATURES
Figure 2. Optional Remote Panel Models 004057 and
Section OPTIONAL REMOTE PANEL
Figure 1. Remote Panel Plug-In Receptacle
GENERAL
Section OPTIONAL REMOTE PANEL
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7.1 GENERATOR & SPEED CONTROL
PART TROUBLE SHOOTING
7.2 ENGINE DC CONTROL SYSTEM/ AC TROUBLESHOOTING
COMPUTER CONTROLLED VARIABLE SPEED RV GENERATORS
Page
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TROUBLESHOOTING REFERENCE CHART
Section GENERATOR & SPEED CONTROL SYSTEM
Section GENERATOR & SPEED CONTROL SYSTEM
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INTRODUCTION
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
PROBLEM 1- PRIMING FUNCTION DOES NOT WORK
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
PROBLEM 2 - ENGINE WILL NOT CRANK
PROBLEM 3 - ENGINE CRANKS BUT WILL NOT START
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PROBLEM 3 - ENGINE CRANKS BUT WILL NOT START CONTINUED
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
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PROBLEM 4 - ENGINE STARTS HARD AND RUNS ROUGH
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
SHUTS DOWN TEST TEST INVERTER Pg FAIL REPLACE INVERTER
PROBLEM 5 - ENGINE STARTS THEN SHUTS DOWN AFTER A FEW SECONDS
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
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Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
PROBLEM 6 - GENERATOR DOESN’T PULL FULL LOAD
PROBLEM 7 - GENERATOR CIRCUIT BREAKER TRIPS / NO AC VOLTAGE
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Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
PROBLEM 8 - ENGINE SHUTS DOWN UNDER LOAD
PROBLEM 9 - GENERATOR LOSES AC POWER THEN SHUTS DOWN
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12-WIRE
PROBLEM 10 - NO AC OUTPUT
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
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PROBLEM 10 - NO AC OUTPUT CONTINUED
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
Figure 2. Primer Switch
TEST 3- CHECK POWER TO FUEL PUMP
TEST 2- CHECK POWER TO PRIMER SWITCH
TEST 1- CHECK 7.5 AMP FUSE
TEST 8- CHECK POWER SUPPLY TO STARTER MOTOR
TEST 6- TEST PRIMER SWITCH
TEST 7- CHECK WIRE 14A TO FUEL PUMP
TEST 4- CHECK BATTERY/BATTERY CIRCUIT
Figure 5. Starter Contactor
TEST 9- CHECK WIRE 56 POWER TO STARTER CONTACTOR
TEST 10- CHECK A6060 CIRCUIT BOARD POWER SUPPLY
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
TEST 11- TEST STARTER CONTACTOR
TEST 12- TEST START-STOP SWITCH
Figure 7. Start-Stop Switch
TEST 13- CHECK FUEL SUPPLY
Figure 9. Ignition Module & 4-Tab Connector
TEST 21 - CHECK A6060 CIRCUIT BOARD OUTPUT TO WIRE
TEST 17- CHECK IGNITION POWER SUPPLY
TEST 18- CHECK IGNITION SENSOR
TEST 24- CHECK ENGINE
TEST 23- CHECK CARBURETION
TEST 22-TEST AUTOMATIC CHOKE
Figure 10. Receptacle J2
Note Cap the DC Link wires with a wire nut for safety
TEST 27- TEST OIL TEMPERATURE SWITCH
TEST 26- TEST OIL PRESSURE SWITCH
TEST 28 - DC LINK VOLTAGE TEST
Note Fluke 87 true RMS meter used in test
TEST 30 - 12 POSITION HARNESS SIGNALS TEST
TEST 29 - 12 POSITION HARNESS CONTINUITY TEST
Figure 10 Free End of 12 Position Harness
Pin 4 Wire #14
STATOR TESTS TEST 32 - POWER SUPPLY WINDING TEST
Figure 11. 12 Position Connector on Inverter
TEST 31 - STATIC TESTS ON INVERTER
TEST 35 - BRIDGE RECTIFIER TEST
TEST 36 - AC POWER WINDING TEST AC1/AC2/SL1/SL2
TEST 34 -STATOR RESISTANCE VALUES
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
Section ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
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Electrical Schematic
PART SPECIFICATIONS AND CHARTS
General Specifications
Wiring Diagram
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NOMINAL RESISTANCES OF GENERATOR WINDINGS
ENGINE SPEEDS AND VOLTAGE SPECIFICATIONS
Part
LOAD %
1 OF
Part SPECIFICATIONS & CHARTS
ELECTRICAL SCHEMATIC DRAWING NO. 0D4947-B
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2 OF
WIRING DIAGRAM DRAWING NO. 0D4947-B
Part SPECIFICATIONS & CHARTS
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GV-220
GENERAL SPECIFICATIONS
MODEL
Part SPECIFICATIONS & CHARTS
CRANKCASE COVER ASSEMBLY
SPECIFICATIONS & CHARTS
CRANKCASE ASSEMBLY
Later model small frame GN engines have no crankshaft sleeve bearing
PISTON
CONNECTING ROD ASSEMBLY
CRANKSHAFT
Part SPECIFICATIONS & CHARTS
MODEL
PISTON CONTINUED
Part SPECIFICATIONS & CHARTS
NOTE 2 Measure pump tip clearance on shaft in crankcase cover
CAMSHAFT ASSEMBLY
OIL PUMP
Part SPECIFICATIONS & CHARTS
MODEL
SPECIFICATIONS & CHARTS
Part
MODEL
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MAJOR FEATURES AND DIMENSIONS GENERATOR
Part SPECIFICATIONS & CHARTS
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MAJOR FEATURES AND DIMENSIONS INVERTER
Part SPECIFICATIONS & CHARTS
