Product Manual
Table Of Contents
- Table of Contents
- Safety
- General Information
- Specifications
- Unit Serial Number Locations
- Component Locations
- Control Panel
- Power Zone™ Gen Controller
- Controller Features and Functions
- Operator Screens
- Alarm Mute
- Auto/Manual Mode
- Navigation Buttons
- Control Power Switch
- Engine Start
- Engine Stop/Reset
- The Liquid Crystal Display (LCD)
- Operator Screens
- Home Screen
- Engine Screen
- Generator Screen
- Voltage Adjust Screen
- Maintenance Screens
- Generator Summary
- Engine Tab
- Generator Tab
- Alarms Tab
- Input/Output Tab
- Schedule Tab
- Status Tab
- Generator Monitoring
- Engine Monitoring
- Controller Information Displays, Functions and Reset
- Belt Tensioners
- Operation
- Prestart Checklist
- Manual Starting of the Unit
- Auto (Remote) Starting of the Unit
- Derating for Altitude
- Generator Output Connection Lugs
- Fine Voltage Adjustment
- Voltage Selector Switch
- Voltage Regulation
- Customer Convenience Receptacles
- Main Circuit Breaker
- Exhaust Filter Cleaning Operations
- Transfer Switch
- Auto Exercise Timer
- Shutting Down the Unit
- Emergency Stop Switch
- Idle Switch (MMG25I-45I only)
- Towing the Unit
- Lifting the Unit
- Maintenance
- Emissions Information
- Daily Walk Around Inspection
- General Maintenance
- Basic Maintenance Schedule - Isuzu Engine
- Basic Maintenance Schedule - John Deere Engine
- Isuzu Engine Break-In Requirements
- John Deere Engine Break-In Requirements
- Resetting the Maintenance Alarms
- Checking Generator Drive Plate Torque
- Jack Maintenance
- Trailer Wheel Bearings
- Troubleshooting
- Wiring Diagrams
- AC Wiring - MMG25IF4, MMG45IF4
- AC Wiring - MMG35DF4, MMG55DF4
- AC Wiring - 4 Pos. Voltage Selector Switch Option - MMG25IF4, MMG45IF4
- AC Wiring - 4 Pos. Voltage Selector Switch Option - MMG35DF4, MMG55DF4
- AC Wiring Option - Standard Receptacles
- AC Wiring Option - Engine Heater
- AC Wiring Option - Buck Transformer
- AC Wiring Option - PMG
- DC Wiring
- Trailer Lights Wiring
- Wiring Harness - Electric Brake Option
- DC Wiring Option - 12V Battery Charger
- DC Wiring Option - Low Oil Level
- Options & Accessories
36949 B MMG25I-35D-45I-55DF4 Operating Manual 37
Section 4 - Maintenance
EMISSIONS INFORMATION
For emissions information, see the OEM engine manual.
DAILY WALK AROUND INSPECTION
Look for conditions that could hinder performance or safety, such as (but not limited to) oil/coolant/fuel leakage,
blocked vents, loose/missing hardware, and electrical connections.
Visually inspect the fan belt for cracks, fraying, stretching, and verify the belt is properly seated in the pulley grooves.
Replace the belt according to the manufacturer’s recommendations.
Note: At the 500 hour/12 month service interval, it is recommended that the belt be removed and checked for wear.
While the belt is removed, inspect pulleys and bearings. Rotate and feel for hard turning or unusual sounds. If pulleys
or bearings need replacement, contact the engine manufacturer.
Failure to perform a daily inspection may result in serious damage to the prime mover.
GENERAL MAINTENANCE
Normal maintenance service and replacement of parts are the responsibility of the owner and are not considered
defects in materials or workmanship within the terms of the warranty. It is strongly recommended that the equipment
be periodically checked by an Independent Authorized Service Dealer.
Poorly maintained equipment can become a safety hazard. In order for the equipment to operate safely and properly
over a long period of time, periodic maintenance and occasional repairs are necessary. NEVER perform routine
service (oil/filter changes, cleaning, etc.) unless all electrical components are shut off. Before servicing the unit,
always follow the instructions listed below.
• Verify the Control Power switch is turned OFF (O).
• Verify the circuit breakers are turned OFF (O).
• Activate (push in) the emergency stop switch.
• Disconnect the negative (-) terminal on the battery.
• Attach a “Do Not Start” sign to the control panel. This will notify everyone that the unit is being serviced and
will reduce the chance of someone inadvertently trying to start the unit.
• Never wash the unit with a high pressure hose or with any kind of power washer.
• Never wash the engine block or fuel tank with a power washer or steam cleaner. Water may enter the cabinet
and collect in the generator windings or other electrical parts, causing damage.
• If the unit is stored outside, check for water inside the cabinet and generator before each use. If wet, dry the
unit thoroughly before starting.
• Inspect condition of electrical cords. DO NOT use the unit if insulation is cut or worn through.
• Check condition of the air filter by viewing the level of the vacuum draw on the filter minder gauge. Replace
the air filter when the yellow center bar reaches the red section on the gauge (20 in. H
2
O).
• Check wheel lugs. See Towing the Unit.
• Check coolant level daily. Refer to the engine operator’s manual for coolant recommendations and proper
mixture.
○ Coolant is checked visually by inspecting the level in the coolant overflow jug located near the radiator.
○ Normal operating level is between the FULL and ADD markings on the overflow jug, which is known as










