Leaf blower running rough: Common Causes & How to Fix
1Leaf Blower Carburetor
Most Common Solution
Repair Instructions:
The issue could be a clogged carburetor. This often happens when old fuel sits in the engine too long. Over time, some ingredients evaporate leaving a thicker, stickier residue. This gunks up the carburetor causing rough running. If you suspect a clogged carb, try cleaning it out with carb cleaner. If that doesn't work, you may need to rebuild or replace the entire carburetor. Gas can start to go bad in as little as 30 days. Additives that keep it fresh evaporate first. What's left is a varnish-like substance that doesn't flow well. This slowly blocks the tiny carb jets and passages, restricting fuel to the engine. Soon it causes sputtering and stall outs. Simply draining old gas isn't enough - the carburetor remains coated in debris. Rebuilding or replacing the carburetor removes all contaminated material for free flow again.
How to Replace a Leaf Blower Carburetor
- Disconnect the spark plug. Use a spark plug wrench to remove the spark plug from the engine. This prevents accidental starting while working.
- Remove air filter cover and air filter. Locate the air filter housing, usually on the rear or side of the blower. Remove cover and take out air filter.
- Remove fuel line and drain fuel. Locate the fuel line connected to the carburetor. Use pliers to pinch closed the fuel line, then disconnect it from the carburetor. Drain the remaining fuel from the fuel tank into an approved container.
- Remove carburetor. Locate the carburetor, usually at the rear or bottom of the engine. Remove any bolts or screws securing it to the engine. Carefully detach any linkages or lines connected to the carburetor. Lift off the carburetor.
- Install new carburetor. Carefully install the new carburetor, attaching any linkages or lines. Make sure the carburetor is securely bolted to the engine.
- Reconnect fuel line. Attach the fuel line back to the inlet on the new carburetor. Make sure the connection is tight.
- Reinstall air filter and cover. Put the air filter back in the housing and replace the cover.
- Reconnect spark plug. Screw the spark plug back into place and tighten it with a wrench.
- Test blower. Add fresh fuel to the tank. Try starting the blower, testing for smooth operation. Make any adjustments as needed.
2Leaf Blower Carburetor Repair Kit
Most Common Solution
Repair Instructions:
The issue could be a clogged carburetor. This often happens when old fuel sits in the engine too long. Over time, some ingredients evaporate leaving a thicker, stickier residue. This gunks up the carburetor causing rough running. If you suspect a clogged carb, try cleaning it out with carb cleaner. If that doesn't work, you may need to rebuild or replace the entire carburetor. Gas can start to go bad in as little as 30 days. Additives that keep it fresh evaporate first. What's left is a varnish-like substance that doesn't flow well. This slowly blocks the tiny carb jets and passages, restricting fuel to the engine. Soon it causes sputtering and stall outs. Simply draining old gas isn't enough - the carburetor remains coated in debris. Rebuilding or replacing the carburetor removes all contaminated material for free flow again.
How to Replace a Leaf Blower Carburetor Repair Kit
- Disconnect the spark plug. Use a spark plug wrench to remove the spark plug from the engine. This prevents accidental starting.
- Remove air filter cover and air filter. Locate the air filter housing, usually on the rear or side of the blower. Remove cover and take out air filter.
- Remove carburetor. Follow fuel line draining steps from previous instructions. Locate the carburetor, detach any lines/linkages and remove screws to detach it from the engine.
- Disassemble the carburetor. Use small screwdrivers to remove the carburetor bowl and float. Carefully detach the needle valve and seat. Spray carburetor cleaner to remove grime.
- Install new parts from kit. Replace needle valve, seat, gaskets, and diaphragms per kit instructions. Make sure parts are clean.
- Reassemble carburetor. Attach float, needle valve, and reinstall carburetor bowl. Tighten screws securely.
- Install carburetor. Carefully install the carburetor back onto the engine, attaching linkages and lines. Make sure the carburetor is securely bolted.
- Replace air filter and cover. Put the air filter back in the housing and replace the cover.
- Reconnect spark plug. Attach the spark plug and tighten it with a wrench.
- Test blower. Add fresh fuel and start blower, testing for smooth operation. Make any adjustments as needed.
3Leaf Blower Spark Arrestor
Common Solution
Repair Instructions:
The spark arrestor is a small screen that prevents dangerous sparks from the engine. Over time, soot can clog up the screen. If clogged, the engine will run rough. To fix, remove and clean the arrestor with a wire brush. Or just replace it if too dirty. The arrestor stops hot particles from exiting the muffler. As the exhaust gases pass through, carbon gradually builds up on the mesh screen. Excess debris starts choking airflow, causing poor performance. A clogged arrestor also poses a fire hazard risk if hot sparks get through. Simply blowing compressed air may not fully clear heavy carbon deposits. Scrubbing with a brush or swapping in a new arrestor ensures it is clean and unclogged.
How to Replace a Leaf Blower Spark Arrestor
- Locate the spark arrestor. The spark arrestor is typically found on the muffler exhaust port. Refer to your owner's manual for the exact location.
- Allow the muffler to cool. Run the engine for a few minutes to warm up the exhaust system. Then shut off the engine and allow the muffler to cool completely to avoid burns.
- Remove the muffler. Detach any brackets or bolts securing the muffler. Carefully pull the muffler off the exhaust port.
- Remove old spark arrestor. Use a socket wrench to unscrew the spark arrestor from inside the exhaust port. Wear gloves as it may be hot.
- Clean the exhaust port. Use a wire brush to scrub away any carbon deposits inside the exhaust port.
- Install new spark arrestor. Thread the new spark arrestor into the exhaust port and tighten securely with the socket wrench.
- Reattach muffler. Carefully realign the muffler over the exhaust port. Resecure using the brackets and bolts.
- Start and test blower. Start the engine and let it run for several minutes. Check for exhaust leaks at the spark arrestor connections.
- Perform safety checks. Inspect the area for flammable debris. Review proper operation and safety procedures before using the blower.
4Leaf Blower Fuel Filter
Common Solution
Repair Instructions:
The issue could be a clogged fuel filter. This often happens when old gas sits in the engine too long. Over time, some ingredients evaporate, leaving a thicker, stickier residue. This gunks up the fuel filter, causing rough running. If old fuel was left in the tank, drain it completely. Then replace the fuel filter to clear the clog. Gas can start to go bad in as little as 30 days. Additives that keep it fresh evaporate first. What's left is a varnish-like substance that doesn't flow well. This slowly blocks the tiny filter pores, restricting fuel to the engine. Soon it causes sputtering and stall outs. Simply draining the stale fuel isn't enough - the filter remains coated in debris.
How to Replace a Leaf Blower Fuel Filter
- Locate the fuel filter. The fuel filter is usually found along the fuel line, often near the fuel tank. Refer to your owner's manual for the exact location.
- Pinch closed the fuel line. Use pliers to pinch the fuel line closed on both sides of the fuel filter. This prevents fuel from draining out when the filter is removed.
- Remove the retaining clips. The fuel filter is held in place with retaining clips. Use a flathead screwdriver to pry these clips off the fuel line.
- Slide the old filter out. With the retaining clips removed, you can now slide the old fuel filter off the fuel line.
- Inspect the fuel lines. Check the fuel lines for cracks or damage. Replace any damaged sections of the fuel line.
- Slide the new filter into place. Align the new fuel filter on the fuel line with the arrow pointing toward the carburetor. Push it into place.
- Secure with retaining clips. Push the retaining clips back over the fuel line on both sides of the new filter to hold it in place.
- Open fuel valve and check for leaks. Turn on fuel valve and check for leaks at the fuel filter connections. Tighten if any leaks are present.
- Start blower and test. Start the leaf blower and let it run for several minutes, checking for smooth operation. Watch for any leaks from the new fuel filter.
5Leaf Blower Air Filter
Common Solution
Repair Instructions:
The issue could be a clogged air filter. A blocked filter starves the engine of air. Without enough air, too much fuel enters the engine. This makes the engine run poorly. If the filter is clogged, replace it right away. The air filter keeps dust and debris out of the engine. Over time, it collects particulates and gets dirty. Excess buildup starts restricting airflow. This lean fuel mixture causes sputtering, power loss, and rough idle. Simply cleaning old filters may not remove deep clogs. Replacing with a brand new filter ensures full air volume for smooth operation.
How to Replace a Leaf Blower Air Filter
- Locate the air filter. The air filter is typically housed in a plastic casing on the side or rear of the blower. Refer to your owner's manual for exact location.
- Open the air filter housing. Release any clasps or screws and remove the air filter housing cover.
- Remove the old air filter. Gently pull out the old air filter, being careful not to dislodge any debris into the carburetor intake.
- Inspect the air filter housing. Check inside the housing for dirt buildup. Wipe away any debris with a clean rag.
- Check the new air filter. Examine the new filter for any defects. Make sure it is the right size and shape.
- Insert the new air filter. Carefully slide the new air filter into the air filter housing. Make sure it fits snugly in place.
- Replace the air filter housing cover. Replace the housing cover and tighten any screws or clasps to secure it.
- Check for air leaks. Start the blower and listen for any whistling noises indicating air leaks. Tighten housing if leaks are heard.
- Clean any dirt buildup. Use a small vacuum to clean away any dirt built up on the blower vents or intake openings.
- Test operation. Run the blower for several minutes, checking for smooth airflow and making any adjustments as needed.
6Leaf Blower Spark Plug
Common Solution
Repair Instructions:
Check the spark plug for wear or damage. Look for cracked porcelain, burnt or broken electrodes, or heavy carbon deposits. If found, replace the plug. Also test the plug with a spark tester. You should see a strong blue spark while cranking. No spark means the plug needs replacing. The spark jumps the electrode gap to ignite the fuel-air mix. Cracks and carbon prevent a clean spark. Worn electrodes have widened gaps that weaken the spark. Testing confirms the plug is firing properly under compression. No visible spark points to a bad plug unable to ignite the engine. Replace worn or damaged spark plugs to restore strong sparking.
How to Replace a Leaf Blower Spark Plug
- Disconnect the spark plug wire. Use a spark plug wrench to remove the wire from the spark plug. This prevents accidental electric shocks.
- Locate and access the spark plug. The spark plug is usually found on the front or side of the engine. Refer to the owner's manual for the exact location. Remove any covers or shrouds blocking access.
- Clean the spark plug area. Use a wire brush or rags to clean away any dirt, oil or debris around the spark plug. This allows easier access and prevents debris falling into the cylinder.
- Remove the old spark plug. Place the spark plug wrench over the plug and turn counterclockwise to unthread it. Pull the plug out of the cylinder head.
- Inspect the old spark plug. Check for heavy carbon buildup or worn electrodes. This can indicate issues like a rich fuel mixture.
- Check spark plug gap. Use a feeler gauge tool to check the gap against manufacturer specs, usually 0.02 - 0.03 inches.
- Install the new spark plug. Carefully thread the new plug clockwise into the cylinder head. Tighten to manufacturer torque specs using the plug wrench.
- Reconnect spark plug wire. Push the wire securely onto the top of the new spark plug.
- Replace covers and shrouds. Reinstall any removed covers or shrouds to protect the engine.
- Test operation. Start the blower and let run for several minutes, checking for smooth performance. Monitor for misfires.