1. Introduction
This manual provides detailed instructions for the safe and proper use of your Powerhorse 27000 Surge Watt, 18000 Rated Watt Electric Start Generator. Please read this manual thoroughly before operating the generator to ensure safe operation and to prevent damage to the unit or personal injury. Keep this manual for future reference.
The Powerhorse Generator is designed to provide reliable power for various applications, including jobsite trailers, air compressors, large electric welders, air conditioners, and as a home backup power source during emergencies. It features a 100% copper-wound generator head for continuous operation and an automatic voltage regulator for consistent power, making it suitable for sensitive electronics (less than 5% THD).
2. Safety Information
WARNING: Operating this generator improperly can lead to serious injury or death. Always follow safety guidelines.
- Carbon Monoxide Hazard: Generators produce carbon monoxide, a colorless, odorless, poisonous gas. Operate the generator outdoors only, far away from windows, doors, and vents. Never operate in an enclosed area.
- Electrical Shock Hazard: Do not operate the generator in wet conditions. Ensure all electrical connections are dry and properly grounded. Use ground fault circuit interrupter (GFCI) protected extension cords.
- Fire Hazard: Gasoline is highly flammable. Refuel in a well-ventilated area with the engine off and cool. Do not smoke or allow open flames near the generator. Store fuel in approved containers away from living areas.
- Hot Surfaces: The generator engine and muffler become very hot during operation and remain hot for a period after shutdown. Avoid contact with hot surfaces to prevent burns.
- Moving Parts: Keep hands, feet, hair, and clothing away from moving parts to prevent injury.
- Hearing Protection: Prolonged exposure to generator noise can cause hearing damage. Wear appropriate hearing protection during operation.
- California Proposition 65 Warning: This product is not for sale in California.
3. Components and Controls
Familiarize yourself with the various components and controls of your Powerhorse Generator before operation.

Figure 3.1: Front view of the Powerhorse 27000/18000 Watt Electric Start Generator, showing the control panel, engine, and wheels.

Figure 3.2: Side view of the generator highlighting the control panel with various outlets and circuit breakers.
- Control Panel: Contains power outlets, circuit breakers, and the multimeter.
- Electric Start: Key switch or button for easy engine starting.
- Fuel Tank: Large 17-gallon capacity with a fuel gauge.
- Engine: 4-stroke engine with a cast iron cylinder sleeve for durability.
- Air Cleaner: Industrial 2-stage air cleaner protects the engine.
- Wheels and Handles: 13-inch flat-free tires and folding handles for portability.
4. Setup
4.1 Unpacking and Assembly
Carefully remove the generator from its packaging. Inspect for any shipping damage. Assembly typically involves attaching the wheels and handles. Refer to the assembly diagrams in the separate assembly guide for detailed steps.
4.2 Adding Engine Oil
- Place the generator on a level surface.
- Locate the oil fill cap/dipstick.
- Remove the cap/dipstick and slowly add the recommended engine oil (refer to specifications for type and capacity) until it reaches the full mark on the dipstick. Do not overfill.
- Replace the oil fill cap/dipstick securely. The generator features pressure lubrication with low oil pressure shutdown for engine protection.
4.3 Adding Fuel
WARNING: Use fresh, unleaded gasoline. Do not use E85 or mixed fuels. Refuel in a well-ventilated area with the engine off and cool.
- Ensure the generator is off and cool.
- Open the fuel tank cap.
- Slowly pour gasoline into the tank, being careful not to overfill. Leave space for fuel expansion. The tank capacity is 17 gallons.
- Securely close the fuel tank cap.
4.4 Connecting the Battery (for Electric Start)
Connect the battery cables according to the instructions provided with the battery. Ensure correct polarity (positive to positive, negative to negative) to avoid electrical damage.
5. Operating Instructions
5.1 Pre-Start Checks
- Check engine oil level.
- Check fuel level.
- Ensure all electrical loads are disconnected from the generator.
- Verify the generator is on a level surface and in a well-ventilated outdoor area.
5.2 Starting the Engine (Electric Start)
- Turn the fuel valve to the "ON" position.
- Move the choke lever to the "CHOKE" position (if the engine is cold).
- Insert the key into the ignition switch and turn it to the "START" position, or press the electric start button. Release once the engine starts.
- Once the engine starts, slowly move the choke lever to the "RUN" position.
- Allow the engine to warm up for a few minutes before connecting electrical loads.
5.3 Connecting Electrical Loads
After the generator has warmed up, you can connect your electrical devices. Ensure the total wattage of connected devices does not exceed the generator's rated wattage (18,000 Watts) to prevent overload. The generator's automatic voltage regulator and less than 5% THD allow for safely running sensitive electronics.
- Plug your devices into the appropriate outlets on the control panel.
- If a circuit breaker trips, reduce the load, then reset the breaker by pushing it in.
5.4 Stopping the Engine
- Disconnect all electrical loads from the generator.
- Allow the engine to run for a few minutes without load to cool down.
- Turn the ignition key to the "OFF" position.
- Turn the fuel valve to the "OFF" position.
6. Maintenance
Regular maintenance is crucial for the longevity and reliable operation of your generator. Perform checks at the intervals specified in the maintenance schedule (refer to a separate detailed maintenance guide if provided).
6.1 Engine Oil
- Check oil level before each use.
- Change oil after the first 20 hours of operation, then every 100 hours or annually, whichever comes first.
6.2 Air Filter
The industrial 2-stage air cleaner should be inspected regularly and cleaned or replaced as needed, especially when operating in dusty conditions. A dirty air filter can reduce engine performance and lifespan.
6.3 Spark Plug
Inspect the spark plug annually or every 100 hours. Clean or replace if fouled or worn. Ensure proper gap setting.
6.4 Fuel System
If storing the generator for an extended period (over 30 days), drain the fuel tank and carburetor, or use a fuel stabilizer to prevent fuel degradation.
6.5 General Cleaning
Keep the generator clean and free of debris. Regularly check for loose fasteners or damaged components.
7. Troubleshooting
This section outlines common issues and their potential solutions. For problems not listed here, contact customer support.
| Problem | Possible Cause | Solution |
|---|---|---|
| Engine will not start | No fuel Low oil level Choke not set correctly Spark plug issue Battery discharged (electric start) | Add fresh fuel Add engine oil Adjust choke Inspect/replace spark plug Charge/replace battery |
| No power output | Circuit breaker tripped Overload Faulty connection | Reset circuit breaker Reduce connected load Check all connections |
| Engine runs rough | Stale fuel Dirty air filter Spark plug issue | Drain and refill with fresh fuel Clean/replace air filter Inspect/replace spark plug |
8. Specifications
Key technical specifications for the Powerhorse 27000/18000 Watt Electric Start Generator.
| Feature | Specification |
|---|---|
| Model Number | 3813349 |
| Brand | Powerhorse |
| Surge Wattage | 27000 Watts |
| Rated Wattage | 18000 Watts |
| Fuel Type | Gasoline |
| Power Source | Fuel Powered |
| Engine Type | 4 Stroke |
| Engine Displacement | 418 Cubic Centimeters |
| Tank Volume | 17 Gallons |
| Item Weight | 599 Pounds |
| Material | Cast Iron |
| Special Feature | Electric Start |
| Total Power Outlets | 1 |
Note: The specification for "Total Power Outlets" as 1 might be a generalization. Refer to the product's control panel for specific outlet configurations.
9. Warranty and Support
For warranty information, please refer to the separate warranty document included with your purchase or visit the official Powerhorse website. Keep your proof of purchase for warranty claims.
If you encounter any issues or require technical assistance, please contact Powerhorse Customer Support. Contact details can typically be found on the manufacturer's website or in your product packaging.
You can also visit the Powerhorse Store on Amazon for additional product information and support resources.





