Chainsaw starts then stalls: Common Causes & How to Fix
1Chainsaw Spark Arrestor
Most Common Solution
Repair Instructions:
The spark arrestor is a small screen that stops sparks from the engine. Over time, soot can clog up this screen. If it gets blocked, the chainsaw may stall or run poorly. To fix it, take the spark arrestor off and scrub it clean with a wire brush. Replacing it is another option too. That little screen prevents dangerous sparks from flying out. But combustion soot can build up and choke the mesh over time. A clogged arrestor restricts proper airflow. Trying to clean it with a brush can remove stuck soot. But if it's really coated, just swapping in a new spark arrestor is best. A clear arrestor screen allows good airflow while still stopping sparks.
How to Replace a Chainsaw Spark Arrestor
- Locate the spark arrestor. It is part of the muffler assembly on the chainsaw. Consult your owner's manual for the exact location.
- Remove muffler cover. Take off the muffler housing cover screws and detach the cover.
- Detach muffler. Remove bolts or clamps holding the muffler in place and carefully detach it from the chainsaw.
- Remove old spark arrestor. Take out the screws or fasteners holding the damaged spark arrestor screen and remove it from the muffler body.
- Install new spark arrestor. Place the new spark arrestor into the muffler and attach using the same screws or fasteners. Tighten securely.
- Reattach muffler. Position the muffler back onto the chainsaw exhaust outlet. Replace bolts or clamps to firmly reattach it.
- Replace muffler cover. Attach the muffler housing cover and insert all screws. Tighten down completely.
- Test chainsaw. Start up the chainsaw and let it run for a few minutes, checking for any exhaust leaks.
- Perform maintenance. Make sure to clean the new spark arrestor regularly as part of the required maintenance.
2Chainsaw Carburetor
Most Common Solution
Repair Instructions:
The issue could be a clogged up carburetor. This happens when old gas sits in the chainsaw. Over time, some fuel ingredients evaporate, leaving a thicker, stickier substance. That sticky residue can choke the carburetor and prevent starting. Try cleaning the carb with spray cleaner. If that doesn't work, rebuild or replace the whole carburetor. Letting gas sit turns it thick and gummy. Those deposits block proper fuel flow through the carb. First, spray cleaner into the carb to dissolve built-up gunk. But if old gas was left for too long, the carb may be too clogged internally. Rebuilding or replacing gets fuel flowing correctly again. Removing stale gas and fixing a choked carb can get the engine starting and running smoothly.
How to Replace a Chainsaw Carburetor
- Disconnect the spark plug. Unscrew and remove the spark plug wire to ensure the engine won't accidentally start while working.
- Remove air filter and cover. Take out the air filter and unscrew any caps or covers necessary to access the carburetor. Refer to your model's manual.
- Drain old fuel. Tip the chainsaw to drain any remaining fuel from the gas tank and lines. Catch it in a container.
- Detach fuel lines. Use a small flathead screwdriver to detach the fuel lines from the carburetor inlet and outlet.
- Remove carburetor. Take out any screws securing the carburetor. Carefully remove it from the engine compartment.
- Install new carburetor. Place the new carburetor into position and reattach the screws. Make sure it is seated properly before tightening the screws.
- Reconnect fuel lines. Attach the inlet and outlet fuel lines to the corresponding fittings on the new carburetor.
- Replace air filter and covers. Reattach the air filter, engine cover, and any other caps or covers. Tighten screws securely.
- Add fresh fuel. Fill the gas tank with the fresh fuel mixture recommended for your model.
- Reconnect spark plug. Attach the spark plug wire and make sure it is seated firmly.
- Test chainsaw. Start engine and test run to ensure proper functioning. Make adjustments as needed.
3Chainsaw Carburetor Repair Kit
Common Solution
Repair Instructions:
The issue could be a clogged up carburetor. This happens when old gas sits in the chainsaw. Over time, some fuel ingredients evaporate, leaving a thicker, stickier substance. That sticky residue can choke the carburetor and prevent starting. Try cleaning the carb with spray cleaner. If that doesn't work, rebuild or replace the whole carburetor. Letting gas sit turns it thick and gummy. Those deposits block proper fuel flow through the carb. First, spray cleaner into the carb to dissolve built-up gunk. But if old gas was left for too long, the carb may be too clogged internally. Rebuilding or replacing gets fuel flowing correctly again. Removing stale gas and fixing a choked carb can get the engine starting and running smoothly.
How to Replace a Chainsaw Carburetor Repair Kit
- Remove the carburetor. Follow the steps to detach fuel lines, and screws, and carefully remove the carburetor from the chainsaw.
- Disassemble the carburetor. Take apart the carburetor by removing gaskets, needles, nozzle, fuel lines, and any other components that will be replaced in the kit.
- Clean the carburetor. Use carburetor cleaner and small wire brushes to thoroughly clean all components and passages.
- Install new parts from kit. The repair kit should include new gaskets, o-rings, needles, nozzle, and sometimes fuel lines. Carefully replace the old components with new ones.
- Reassemble carburetor. Put all the cleaned components and new parts back together in the proper configuration for your model. Consult the manual for assembly.
- Adjust carburetor. Make proper adjustments to idle speed, fuel/air mixture according to manufacturer specifications.
- Reinstall carburetor. Place the rebuilt carburetor back into the chainsaw and reattach all fuel lines, linkage, and securing screws.
- Replace covers. Put air filter, engine cover, and all other housings back on the chainsaw and secure.
- Test chainsaw. Start the engine and test run the chainsaw to ensure proper functioning. Make any additional tuning as needed.
4Chainsaw Fuel Filter
Common Solution
Repair Instructions:
The fuel filter could be choked up. This happens when old gas is left in the chainsaw. Over time, some fuel ingredients evaporate, leaving a thicker, stickier substance. That sticky residue can clog the fuel filter and make the engine stall. If old fuel was sitting in there, drain the tank completely. Then replace the fuel filter. Letting gas sit turns it thick and gummy. Those deposits block proper fuel flow through the filter. Draining the tank removes the stale fuel. Putting in fresh gas alone won't fix it. The filter also needs to be replaced to remove blockages.
How to Replace a Chainsaw Fuel Filter
- Locate the fuel filter. It is usually found along the fuel line, before the carburetor. Check your owner's manual.
- Clip fuel line. Use a pair of pliers to detach the fuel line on both sides of the old filter.
- Remove old filter. Slide the filter off the fuel line. Inspect for debris.
- Install new filter. Place the new fuel filter onto the fuel line, with the directional arrow pointing towards the carburetor.
- Secure fuel line. Attach the fuel line back on both sides of the filter using the pliers. Ensure a tight seal.
- Replace fuel cap. Tighten the fuel tank cap back on securely.
- Check for leaks. Start the chainsaw and inspect the fuel line connections near the new filter for potential leaks.
- Clean air filter. It's best to replace the air filter at the same time as the fuel filter. Refer to your owner's manual.
- Dispose of old fuel. Properly dispose of old fuel and clean out the fuel tank if contaminated.
- Add fresh fuel. Refill the tank with new, clean fuel recommended for your chainsaw model.
5Chainsaw Air Filter
Common Solution
Repair Instructions:
The issue could be a clogged or dirty air filter. A blocked filter means the engine gets too much fuel and not enough air. That lack of air will make the engine stall or run rough. Check the filter to see if it's choked with dirt. If it is clogged up, you'll need to swap in a new air filter. That filter has to let enough clean air into the engine. Dirt and debris can build up in the filter over time, restricting airflow. Without enough air mixing with fuel, the engine can't run properly.
How to Replace a Chainsaw Air Filter
- Locate air filter. It is housed under the filter cover on the side of the chainsaw. Refer to the manual for the exact location.
- Remove filter cover. Unscrew the air filter cover screws and remove the cover.
- Take out old filter. Gently pull the old air filter out of the housing. Some are spring-loaded.
- Inspect filter. Look for damage or heavy dirt buildup. A very dirty filter indicates improper maintenance.
- Clean housing. Use a small brush and vacuum to remove dirt and debris inside the empty air filter housing.
- Install new filter. Place the new air filter inside the housing, with the pleated paper side facing out. Replace any springs.
- Replace filter cover. Put the air filter cover back on and tighten down the screws securely.
- Check chain tension. Examine the chain tension and adjust if needed before use.
- Start chainsaw. Run the chainsaw to ensure proper airflow and performance. Monitor for issues.
- Maintain regularly. Check and replace air filter at intervals specified in owner's manual.