Introduction
This manual provides essential instructions for the proper installation, operation, and maintenance of your RHYTHM TESTAMENT Carburetor, designed specifically for Generac Guardian 15kW engines, model OE6221. Please read this manual thoroughly before proceeding with installation or operation to ensure safe and efficient use.
Product Overview
The RHYTHM TESTAMENT Carburetor is engineered for Generac Guardian 15kW engines (model OE6221). It is designed to ensure accurate fuel-air mixing for consistent generator output, smooth startup, and efficient combustion. This carburetor optimizes engine performance, promotes cleaner burning, minimizes exhaust emissions, and extends engine life under continuous use. It is ideal for restoring lost power or replacing a worn factory carburetor.
Safety Information
WARNING: Always disconnect the spark plug wire and fuel line before working on the carburetor or engine to prevent accidental startup and fuel spills.
CAUTION: Gasoline is highly flammable. Work in a well-ventilated area away from open flames or sparks. Wear appropriate personal protective equipment (PPE) such as gloves and eye protection.
Ensure the engine is cool before performing any maintenance or installation.
Package Contents
Verify that all components are present before beginning installation. Your package should include:
- 1x Carburetor Assembly
- 2x Gaskets
- 2x Fuel Filters
- 1x Wiring Harness

Setup and Installation
Tools Required:
Basic hand tools (wrenches, screwdrivers), fuel line clamps, clean rags.
Preparation:
- Turn off the generator and allow the engine to cool completely.
- Disconnect the spark plug wire to prevent accidental starting.
- Shut off the fuel supply valve.
- Place a suitable container under the carburetor to catch any spilled fuel.
Removal of Old Carburetor:
- Carefully disconnect the fuel line from the old carburetor.
- Disconnect any throttle linkages, choke linkages, and electrical connections (e.g., solenoid wire).
- Unbolt the old carburetor from the engine manifold. Note the position of any gaskets.
- Remove the old carburetor and discard old gaskets.
Installation of New Carburetor:
- Ensure the mounting surfaces on the engine and air filter housing are clean and free of debris.
- Place new gaskets in their correct positions.
- Mount the new RHYTHM TESTAMENT Carburetor onto the engine manifold, ensuring proper alignment.
- Secure the carburetor with the mounting bolts, tightening them evenly.
- Reconnect the throttle linkages, choke linkages, and electrical connections (wiring harness).
- Install the new fuel filters in the fuel line as appropriate.
- Reconnect the fuel line to the carburetor.
- Reconnect the spark plug wire.

Operating Instructions
After installation, perform the following steps before starting the engine:
- Ensure all connections are secure and there are no fuel leaks.
- Open the fuel supply valve.
- Check the engine oil level.
- Follow your generator's manufacturer instructions for starting the engine.
- Allow the engine to run for a few minutes to stabilize and check for smooth operation and any unusual noises or leaks.
Maintenance
Regular maintenance ensures optimal performance and extends the life of your carburetor.
- Fuel System: Use fresh, clean fuel. Stale or contaminated fuel can clog the carburetor. Consider using a fuel stabilizer if the generator will be stored for extended periods.
- Fuel Filters: Replace fuel filters periodically, or if they appear dirty or clogged, to prevent debris from reaching the carburetor.
- Air Filter: Ensure the engine's air filter is clean and properly installed. A dirty air filter can restrict airflow and affect carburetor performance.
- Cleaning: If the carburetor becomes clogged, it may require cleaning. This typically involves disassembling the carburetor, cleaning jets and passages with carburetor cleaner, and replacing gaskets. Professional service is recommended for complex cleaning.

Troubleshooting
This section addresses common issues that may arise with carburetor operation.
Engine Not Starting:
- Check fuel level.
- Ensure fuel valve is open.
- Verify spark plug is connected and functional.
- Check for fuel flow to the carburetor.
- Inspect carburetor for clogs or blockages.
Engine Runs Rough/Stalls:
- Check for proper air filter installation and cleanliness.
- Inspect fuel lines for kinks or blockages.
- Ensure carburetor mounting bolts are tight.
- Consider carburetor cleaning if fuel quality is suspected.
Excessive Fuel Consumption:
- Check for fuel leaks.
- Ensure choke is not stuck partially closed.
- Carburetor may require adjustment or cleaning.
Specifications
| Brand: | RHYTHM TESTAMENT |
| Model Number: | OE6221 |
| Compatible Engine: | Generac Guardian 15kW Engine |
| Flange Type: | Dual-bore flange |
| Fuel Type: | Gasoline |
| Included Components: | 1x Carburetor, 2x Gaskets, 2x Fuel Filters, 1x Wire Harness |
| Exterior Finish: | Aluminum |
Warranty and Support
For warranty information and technical support, please refer to the RHYTHM TESTAMENT official website or contact your retailer. Keep your purchase receipt as proof of purchase.