Firman T04073 User Manual (English)

Questions and Answers:

K
Kimberly EnglishAug 7, 2025
What to do if my Firman T04073 engine bogs down when a load is connected?
- M
  Melanie BoydAug 7, 2025
  If your Firman Portable Generator's engine is running fine without any load but falters or 'bogs down' when you connect loads, it could be due to a few reasons. First, there might be a short circuit in the connected load, so try disconnecting the electrical load. Another possible cause is a clogged or dirty fuel filter, which would require cleaning or replacement. If these steps don't resolve the issue, it could be due to the engine speed being too slow or a shorted generator circuit, both of which require help from an authorized service facility.
K
Kenneth MartinezAug 10, 2025
Why is my Firman Portable Generator running but has no AC output?
- Y
  yphillipsAug 10, 2025
  If your Firman portable generator's engine is running, but there's no AC output, several factors could be at play. First, check if the circuit breaker is open and reset it if necessary. Also, check for poor connections or defective cord sets and repair them. Try connecting another device that is in good condition to ensure the connected device is not the problem. If none of these steps work, there may be a fault in the generator itself, which requires help from an authorized service facility.
J
Jessica VasquezAug 15, 2025
Why does my Firman T04073 lack power?
- O
  ocruzAug 15, 2025
  If your Firman Portable Generator engine lacks power, it might be due to overloading the generator, so avoid doing that. Another reason might be a dirty air filter, which should be replaced. Also, a clogged or dirty fuel filter can cause this issue, so clean or replace it. Finally, a clogged spark arrester can also reduce power, so clean or replace that as well.
V
vloveAug 19, 2025
What to do if my Firman Portable Generator engine shuts down while running?
- M
  Matthew HuntAug 20, 2025
  If your Firman Portable Generator engine shuts down while running, possible causes include running out of gasoline or LPG/NG, which requires refilling the fuel tank or replacing the LPG cylinder/checking the NG supply. Another cause is a dirty air cleaner, so you should clean or replace it. Also, check for a low oil level and fill the crankcase to the proper level, ensuring the generator is on a level surface.
B
Brian WilliamsAug 25, 2025
Why does my Firman T04073 engine hunt or falter?
- N
  Nicholas GreenAug 25, 2025
  If your Firman Portable Generator engine “hunts” or falters, it could be due to a carburetor running too rich or too lean, which requires help from an authorized service facility. Another possible cause is a clogged or dirty fuel filter, so you should clean or replace it.
S
Shelby PottsAug 28, 2025
What does it mean when my Firman T04073 Portable Generator shuts down and the yellow CO fault light is blinking?
- T
  Travis GriffinAug 28, 2025
  If your Firman Portable Generator engine shuts down and the yellow CO fault light is blinking, this indicates a CO system fault. You should contact an authorized FIRMAN service facility for assistance.

Firman T04073 Specifications

General

Type	Portable Generator
Starting Watts	4000
Running Watts	3500
Fuel Type	Gasoline
Engine Displacement	208cc
Starting System	Recoil
AC Output	120V
Engine Type	4-Stroke
Noise Level	68 dBA
DC Output	12V

Summary

Understanding Signal Words and Safety Symbols

Hazard Levels Explained

Defines hazard levels indicating potential injury or death if ignored.

Key Safety Icons

Explains common safety icons like Safety Alert, Operator's Manual, Toxic Fumes, etc.

Important Safety Information and Usage Guidelines

California Proposition 65 Warning

Warns about potential exposure to chemicals known to cause cancer or reproductive harm.

Generator Usage and Grounding

Outlines generator's intended use and its system grounding connection.

Restoring Home Power

Explains how to connect to home power using transfer switches or extension cords.

Extension Cord Safety and Carbon Monoxide Precautions

Extension Cord Selection

Provides guidelines on selecting appropriate extension cords based on amperage and length.

Carbon Monoxide Dangers

Details the lethal risk of carbon monoxide from generator exhaust.

Home Power Connection Advice

Recommends installing a transfer switch for home power restoration.

Generator Components and Features

Component Identification

Identifies key parts of the generator with corresponding numbers for easy reference.

Critical Operating Safety Guidelines

Carbon Monoxide and Ventilation

Stresses outdoor operation and ventilation due to CO poisoning risk.

Hazard Identification and Prevention

Covers electrical shock, hot surfaces, fire hazards, and proper placement.

Safe Handling and Spill Prevention

Provides guidance on safe operation, storage, and transport to prevent fuel spills.

Specific Safety Precautions and Warnings

Fuel Handling and Emissions Safety

Covers fuel flammability, LPG/NG safety, and California emissions notice.

Component Safety and Maintenance

Addresses hot surfaces, LPG cylinder placement, and spark arrester.

Control Panel Layout and Features

Engine Start and Fuel Selection

Covers fuel selector switch, engine start, and indicator light.

Electrical Output and Protection

Details voltage selector, circuit breakers, and receptacle types.

Fuel Input and Safety Indicators

Describes LPG/NG connectors, selector, and CO Alert indicator.

Safe Generator Location and CO Prevention

Outdoor Operation Requirement

Mandates operating the generator outdoors at least 20 ft from occupied spaces.

Carbon Monoxide Alarm Installation

Advises installing CO alarms and recognizing poisoning symptoms.

Enclosed Space Hazards

Warns against operating in garages, sheds, or other enclosed areas due to CO buildup.

Fire Hazard Prevention

Clearance Requirements for Fire Safety

Specifies minimum clearances from structures, trees, and vegetation to prevent fires.

Weather Protection and Airflow

Recommends dry outdoor sites and avoiding placement under decks that restrict airflow.

Engine Oil Procedures

Oil Type and Viscosity Selection

Recommends oil type and provides a chart for selecting viscosity based on temperature.

Checking and Filling Engine Oil

Details the steps for checking and filling the engine oil, including dipstick use.

Engine Oil and Fueling Procedures

Oil Filling and Level Check

Describes the final steps for filling oil and the importance of regular checks.

Low Oil Shutdown System

Explains the automatic engine shutdown feature due to low oil levels.

Gasoline Fueling Safety

Provides safety instructions for adding gasoline, including cooling time and spill prevention.

Operating Conditions and Adjustments

High Altitude Operation

Explains power reduction and potential adjustments for high altitudes.

High Ambient Temperature Operation

Details performance limitations and considerations for high ambient temperatures.

Fueling Precautions

Reinforces fuel filling safety and avoiding overfilling.

Connecting LPG/NG Fuel

LPG/NG Safety Guidelines

Outlines crucial safety measures for connecting and using LPG/NG fuels.

Fuel Supply Connection Requirements

Details requirements for fuel supply connections, local codes, and flexible fuel lines.

LPG Cylinder Handling

Provides instructions on keeping LPG cylinders upright and verifying cylinder condition.

Fuel Connections and Starting Procedures

Connecting Natural Gas (NG)

Explains connecting Natural Gas sources and ensuring safe placement.

Indicator Lights and Battery Mode

Describes indicator lights for battery saving mode and fuel selection.

Gasoline Starting Preparation

Lists essential checks and outdoor operation requirements before starting on gasoline.

Gasoline Starting Procedure

Fuel Selector and Load Disconnection

Sets the fuel selector to GAS and disconnects electrical loads before starting.

Choke Operation for Starting

Explains how to use the choke lever for starting, noting warm engines.

Starting Methods (Recoil & Electric)

Details the procedures for both recoil and electric starting.

Starting Procedures (Gasoline, LPG)

Post-Start Stabilization (Gasoline)

Advises running the generator at no load to stabilize before connecting loads.

LPG Starting Preparation and Setup

Details pre-start checks, LPG connection, and selector setting.

LPG Cylinder and Fuel Valve Operation

Guides on connecting the LPG hose and opening the cylinder valve.

LPG Starting Steps

Fuel Selection and Load Disconnection (LPG)

Sets fuel selector to LPG/NG and disconnects electrical loads.

Choke Operation for LPG Start

Explains choke usage for LPG starting, including PULL-TO-PRIME.

Starting Procedures (LPG, NG)

Recoil Start Steps (LPG)

Details the PULL-TO-RUN sequence for recoil starting on LPG.

NG Starting Preparation

Covers NG connection, valve operation, and selector setting.

NG Starting Safety

Ensures safe connection of Natural Gas sources and proper valve operation.

NG Starting Steps

Fuel Selection and Load Disconnection (NG)

Sets fuel selector to LPG/NG and disconnects electrical loads.

Choke Operation for NG Start

Explains choke usage for NG starting, including PULL-TO-PRIME.

Recoil Start Procedure (NG)

NG Recoil Start Steps

Details the PULL-TO-RUN sequence for recoil starting on NG.

Connecting Loads and Generator Startup

Electric Start Procedure (NG)

Explains the electric start procedure for NG operation.

Connecting Electrical Loads

Outlines the sequence for connecting electrical loads to the generator.

GFCI Self-Test Procedure

Describes how to perform a self-test on the GFCI receptacles.

Electrical Load Connection Safety

Electrical Cord and Grounding Safety

Warns against using damaged cords and emphasizes proper grounding.

GFCI Operation and Testing

Explains GFCI function, self-test, and troubleshooting.

Surge Protection for Electronics

Recommends surge suppressors for sensitive electronic equipment.

Connecting Loads and Surge Protection

Sequential Load Connection

Details the step-by-step process for connecting electrical loads.

Protecting Sensitive Electronics

Advises on using surge suppressors to protect electronic devices from voltage fluctuations.

CO Alert System and Generator Shutdown

CO Alert System Functionality

Explains the automatic CO shutdown system and indicator lights.

Generator Stopping Procedure

Details the correct steps for shutting down the generator safely.

Generator Stopping Procedure

Fuel Selector and Valve Closure

Covers turning off the fuel selector and closing LPG/NG valves.

Maintenance Schedule

Scheduled Maintenance Items

Lists maintenance tasks and their recommended intervals for various components.

General Maintenance Recommendations

Provides overall advice for improving performance and longevity.

Engine Maintenance Procedures

Generator Transport Safety

Advises on safe transport procedures, including fuel handling.

Engine Oil Change Instructions

Details the process and frequency for changing engine oil.

Air Filter and Spark Plug Maintenance

Air Filter Cleaning and Replacement

Explains how to clean and maintain the air filter element.

Spark Plug Inspection and Replacement

Guides on inspecting, cleaning, and replacing the spark plug.

Spark Plug, Valve, and Exhaust System Maintenance

Spark Plug Gap Adjustment

Provides instructions for adjusting the spark plug electrode gap.

Valve Clearance Maintenance

Specifies the required intake and exhaust valve clearance.

Muffler and Spark Arrester Safety

Warns about hot muffler parts and legal requirements for spark arresters.

Exhaust System Maintenance and General Cleaning

Muffler and Spark Arrester Inspection

Details how to inspect and clean the muffler and spark arrester.

Generator Cleaning and Inspection

Advises on keeping the generator clean and performing pre-use inspections.

Battery Maintenance and Charging

Battery Replacement Procedure

Outlines the steps for replacing the generator's battery.

Battery Charging Information

Explains the automatic charging circuit and manual charging methods.

Long-Term Storage Procedures

Fuel System Preparation for Storage

Advises on using fuel stabilizer and operating the engine to circulate it.

Fuel Tank Storage Options

Explains options for storing with or without fuel, including fuel starvation.

Engine and Generator Storage Steps

Details steps like turning off fuel, changing oil, and protecting the engine cylinder.

Storage Location and Protection

Recommends storing in a clean, dry place away from ignition sources.

Troubleshooting Common Issues

No AC Output or Load Issues

Addresses problems with AC output and engine response under load.

Starting and Running Problems

Covers issues with starting, rough running, or engine shutdown.

Engine Power and Stability Issues

Discusses engine lacking power, hunting, or shutting down.

CO System Faults

Explains how to address issues related to the CO system fault light.

Generator Specifications

Model and Performance Data

Lists model number, starting/running watts, voltage, frequency, and power factor.

Engine and Fuel System Details

Provides information on engine type, displacement, fuel capacity, and oil type.

Fuel Consumption Rates

Details fuel consumption for natural gas and LPG at different load levels.

Parts Diagram

Overall Generator Assembly View

Shows an exploded view of the entire generator with numbered parts.

Engine Parts Diagram

Engine Assembly Breakdown

Displays an exploded view of the engine components with numbering.

Parts List (Generator)

Generator Component Part Numbers

Lists generator parts with their corresponding numbers and quantities.

Parts List (Continued)

Additional Generator Parts

Continues the list of generator components and their part numbers.

Parts List (Engine)

Engine Component Part Numbers

Lists engine parts with their corresponding numbers and quantities.

Wiring Diagram

Electrical System Schematic

Illustrates the electrical connections and components of the generator.

Service and Parts Ordering

Contacting FIRMAN Service

Provides contact information for service and obtaining parts.

Ordering Replacement Parts

Lists information required when ordering replacement parts.

FIRMAN Limited Warranty

Warranty Qualifications and Registration

Details requirements for warranty registration and proof of purchase.

Repair and Replacement Terms

Outlines the terms of the repair/replacement warranty, including duration and exclusions.

Contacting FIRMAN for Service

Advises contacting FIRMAN customer service first for troubleshooting and service authorization.

Warranty Exclusions and Limitations

Excluded Repairs and Conditions

Lists conditions and repairs not covered by the warranty, such as normal wear and misuse.

Warranty Liability Limits

States FIRMAN's disclaimers regarding loss of time, use, freight, and consequential damages.

Contact Information

Provides FIRMAN's address and website for customer inquiries.

Emissions Control System Warranty

Owner's Warranty Responsibilities

Outlines owner's duties like performing maintenance and presenting the unit for service.

Emissions Warranty Provisions

Details warranty periods and conditions for emissions-related parts.

Parts Covered by Emissions Warranty

Lists specific engine parts covered under the emissions warranty.

Emissions Warranty Limitations

Specifies what is not covered by the emissions control system warranty.

Related product manuals