Stihl BR 340 BR 420 Instruction Manual
![Stihl BR 340 BR 420 manual cover](/images/1779fed506b839b50386885c/thumbs/thumb175x175.webp)
To start the Stihl BR 340 or BR 420 blower, ensure the stop switch is in the "I" position, set the choke lever to the closed position, pull the starter rope until you hear the engine fire, then move the choke to the open position and pull the starter rope again until the engine starts.
The Stihl BR 340 and BR 420 require a 50:1 fuel mixture ratio, which means 50 parts gasoline to 1 part 2-stroke engine oil. Always use high-quality oil and gasoline.
It is recommended to check and clean the air filter after every 10 hours of operation. More frequent cleaning may be necessary in dusty conditions. Replace the filter if it shows signs of damage or excessive dirt that cannot be cleaned.
First, check the fuel level and ensure the fuel mixture is correct. Verify that the spark plug is clean and properly gapped. Inspect the air filter for clogs and clean or replace it if necessary. Finally, check the ignition system for any faults.
Adjusting the carburetor should be done by a professional as incorrect settings can damage the engine. However, if necessary, refer to the user manual for the specific procedures and settings. Ensure the air filter is clean before making any adjustments.
Regular maintenance includes checking and cleaning the air filter, inspecting and replacing the spark plug as needed, checking the fuel filter, and ensuring all nuts and bolts are tight. Also, inspect the blower tube and fan for debris buildup.
Before storing, clean the blower thoroughly, empty the fuel tank, and run the engine until it stops to clear the carburetor of fuel. Store in a dry, dust-free environment. Disconnect the spark plug to prevent accidental starting.
Loss of power can be caused by a dirty air filter, a clogged fuel filter, or a fouled spark plug. Check each of these components and clean or replace them as necessary. Also, ensure the carburetor is properly adjusted.
Ensure that all parts are properly assembled and that the anti-vibration mounts are intact and in good condition. Regularly inspect the blower for any loose components and tighten them as needed.
Turn off the engine and disconnect the spark plug for safety. Remove the blower tube and clear any debris manually. Check and clean the fan housing if necessary before reassembling the unit.