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
Maintenance
36949 B MMG25I-35D-45I-55DF4 Operating Manual 41
1
Replace primary air cleaner when dust valve restriction indicator gauge shows a vacuum of 25 in. H
2
O.
2
If not using John Deere Plus 50 II engine oil, the interval must be decreased to every 250 hours.
ISUZU ENGINE BREAK-IN REQUIREMENTS
Note: The EPA final Tier 4 Isuzu engines have an engine break-in duration that will prohibit the unit from providing
rated standby power upon factory delivery. The unit is tested at the factory and is initially capable of a prime standby
power output. The engine performance will increase to 95% of full rated power during the first 20 hours of loaded
operation. The unit will provide full rated power after the complete engine break-in period of 70 hours of loaded
operation.
Operate the engine at heavy loads (60-90% of rated output maximum) as much as possible during the break-in
period. If the engine has spent significant time at idle, constant speed(s) and/or light load or if makeup oil is required,
a longer break in period may be needed. Refer to the engine operator’s manual for a full description of necessary
procedures on the addition of oil and extension of the break-in period. For more information on regular maintenance
intervals, see Basic Maintenance Schedule - Isuzu Engine.
JOHN DEERE ENGINE BREAK-IN REQUIREMENTS
Note: During the first 20 hours of operation, avoid long periods of no load or sustained maximum load operation. If
the generator is to run for longer than five minutes without a load, shut the generator down.
John Deere engines are supplied with engine break-in oil from the factory. Extra care during the first 100 hours of
engine operation will result in better performance and longer engine life. DO NOT exceed 100 hours of operation
with the break-in oil. Operate the engine at heavy loads (60-90% of maximum) as much as possible. If the engine
has spent significant time at idle, constant speed(s), and/or light load, or if makeup oil is required, a longer break in
period may be needed. Refer to the engine operator’s manual for a full description of necessary procedures on the
addition of break-in oil and extension of the break-in period. For more information on regular maintenance intervals,
see Basic Maintenance Schedule - John Deere Engine.
RESETTING THE MAINTENANCE ALARMS
The Power Zone™ controller will display a warning message when the unit is due for maintenance or service. The
maintenance or service interval is set at 250, 500 and 3000 hours of engine running time. Once the unit has been
serviced, the appropriate maintenance alarm reminder needs to be reset. The following procedure demonstrates
how to reset the maintenance alarms:
1. With the unit shut down, move the Control Power switch to ON (I). After initialization, the controller will toggle
automatically to the Home screen.
2. Press ▲, ►, ▼, or ◄ to enter the maintenance screens.
3. Press () and (O) simultaneously. The next screen will display the Configuration menu.
4. Press to move the cursor (blue highlighted text) down to the Maintenance group.
5. Press ► to access the sections. Press to highlight the Maintenance section.
6. Press ► to access the parameters and highlight the maintenance alarm that needs to be reset.
7. Press () to select the editable parameters. The cursor will highlight “Not Reset” under the selected mainte-
nance alarm. Press to highlight “Reset”.
8. Press () to reset the selected maintenance alarm.










