12 Tested Ways to Fix a Chainsaw that Won’t Start

A typical gasoline chainsaw consists of many parts that need proper maintenance and care. Sometimes little issues can cause your chainsaw not to start and stop immediately after starting up. Surprisingly, these issues can be resolved without getting professional help. We have identified the common problems and formulated a guide to help you deal with them. In this article, we will be discussing all these issues and suggest a possible solution. Please note that this is just a theoretical guide that can only be used to identify the problem and solve it. If the problem persists after implementing the advised fix, we suggest you refer to the manufacturer’s repair service/warranty and get the problem sorted out.

Reasons Chainsaw won’t start and their Solutions

Problem # 1: Gas Problems

The most common problem behind a chainsaw not starting up or staying running is that either it is out of gas or you have filled old fuel in it. Gasoline has a short shelf life. If left inside the chainsaw’s gas tank, it will start to rot after 15-20 days. The fuel will evaporate and will leave behind a thick paste-like tar.

Solution: The best way to deal with the problem is to ensure that you have enough gas in your chainsaw before firing it up. To deal with the old gas issues, you need to make sure that you are putting fresh gas in your chainsaw. Storing your chainsaw with gas in it is also detrimental to its carburetor and fuel pump. If the inside of your chainsaw’s gas tank is lined with the black/brown sticky paste, you would need to clean it, add fresh gas, and then start your chainsaw. You can use petrol to clean the inside of the tank.

Problem # 2: Choke Turned off

If you are trying to start your chainsaw with enough fresh gas in it and it won’t respond, it can also happen due to the choke being turned off. Choke is installed to stop/allow air into the carburetor and must be closed when starting a cold chainsaw or one which has not been used in a while.

Solution: Turn the choke on and then try pulling the starting cord. If nothing else is wrong with your chainsaw, it will be up and running in a couple of attempts.

Problem # 3: Spark Plug Issues

Replace spark plug

For any tool having a combustion-based engine, a spark plug is a very critical component. It is also a common reason that your chainsaw won’t start or makes loud bangs while running. A spark plug is responsible for maintaining the electric current needed to run the engine.

Solution: Open the spark plug with the help of a spark plug wrench and then inspect it. The tip of the spark plug must not be dirty, black, or burnt. If it has just a layer of carbon on it, you can clean it. If you don’t know how to inspect a spark plug, take it to a nearby auto mechanic and get it checked. They will tell you about its condition and whether it will work or not. If it is out of order and can’t be used again, but a new one and install it. If the porcelain tip has cracked, the spark plug needs a replacement. Sometimes your chainsaw won’t start due to a faulty installation of the spark plug or a damaged spark plug cable. Spark plug replacement is a must-to-do task in the regular maintenance checklist for your chainsaw.

Problem # 4: Carburetor Problems

A carburetor is like the heart of a chainsaw’s engine. The major reason behind carburetor developing issues is leaving fuel when the chainsaw is not in use. The fuel content in the gas will evaporate over time and leave behind a sticky tar to clog the carburetor. It will stop the gas flow and will prevent your chainsaw from starting and staying running.

Solution: The solution to this problem lies more in prevention rather than a cure. If you want to keep your carburetor in mint condition, make sure you don’t leave gas in it while storing your chainsaw for a long time. However, if you have left gas and cannot start it, you must clean the fuel tank before cleaning the carburetor. If the issue continues, then go for a carburetor repair. Most of the time, simple washing with petrol will do the trick for you. For older models, you may need to rebuild or replace the carburetor.

Problem # 5: Dirty Air Filter

The air filter is responsible for maintaining the air-gas ratio in the carburetor. It is needed to start and keep the engine up and running. If dirty, dusty, or clogged, it will prevent the chainsaw from starting.

Solution: Checking the air filter is also a regular maintenance task. You must check the air filter in the chainsaw before every use or after using it a couple of times. Clean and wash the dirty air filter and then insert it back. If the air filter is damaged or torn up, replace it with a new one. Make sure you go for a manufacturer-approved air filter.

Problem # 6: Clogged Fuel Filter

Clogged filter

A fuel filter is installed to remove any suspended particles in the gas and ensure that the carburetor gets clean fuel. It can get clogged over time and stop your chainsaw from starting. A blocked fuel filter can also be the reason behind your chainsaw won’t stay running, or it takes hiccups while running.

Solution: Check the fuel filter by taking it out from the gas tank. You can use a steel coat hanger for this purpose. Just straighten one end of the hanger and insert one end to bring the filter out. If it has sediment in it, clean it. Make sure that it is not preventing fuel from flowing through it. The fuel filter for chainsaws is cheap. We suggest that you replace it instead of cleaning the old one.

Problem 7: Flooded Engine

A flooded engine can stop your chainsaw from starting. It happens as a result of pushing the fuel pump and primer bulb too many times. The presence of a gas smell indicates it.

Solution: To deal with a flooded engine, you need to eliminate the excessive fuel in it. You can solve this problem by taking out all the fuel in the tank. Pour it into a clean container so that you can use it again. Now turn on the choke and pull the starting cord 8-10 times. Make sure you hold the throttle while doing this. Open the spark plug, clean it, and insert it back. If you have some time, wait for 20-30 minutes before putting the fuel back in and starting the engine. Otherwise, you can start it right away. The chainsaw might be a bit cranky initially, but it will be stable in a couple of minutes after the excessive fuel is burnt.

Problem # 8: Blocked Spark Arrestor

A spark arrestor is a screen that is installed on the spark plug to stop the spark from flying out from the chainsaw when it starts. Over time, it can get blocked and impacts the air-fuel mixture.

Solution: Taking care of the spark plug screen is also included in regular maintenance tasks. It is best to replace it after every 24 hours of use.

All the problems mentioned above are simple and happen frequently. Their solutions are also easy to implement. Let’s look at some of the complex problems which stop your chainsaw from starting.

Problem # 9: Ignition Coil

If you have checked the spark plug, plug cable, and all the above problems, it is good to check the ignition coil. It is responsible for sending an electrical current to the spark plug while the engine is running. A default ignition coil may not prevent the chainsaw from starting, but it will not keep it running.

Solution: After checking the spark plug, you may check the ignition coil with an ignition coil testing kit. It can be brought online or from a hardware/auto supplies store. Ignition coil testing kits are critical for people who have engine-based tools at their home, like a chainsaw and a generator. If you are lucky, a simple repair will sort out the faulty ignition coil, or you may need to replace it with a new one.

Problem # 10: Starting Cord Problems

Apart from the issues mentioned earlier, the starting cord setup can also have some problems. It consists of a rewind spring, recoil starting assembly, and recoil start pulley. The rewind spring is responsible for rewinding the starter cord after every time you pull it. If the spring is damaged or misplaced, it won’t pull the cord back properly, and you won’t be able to start the chainsaw. To check the recoil starting assembly, you will need to open it and check everything is working and in order. You can refer to the user manual to see the correct arrangement. The recoil start pulley is also responsible for retracting the starting rope. Any issue with the three pieces of equipment will not let you start the chainsaw.

Solution: All the things mentioned above will need to be opened and then rearranged or replaced. Every model has a different mechanism, and hence you must check the instruction manual for repairing or replacing them.

Problem # 11: Compression Rings

Compression rings are responsible for running the engine smoothly. A fault in them will lead to gas not being burned properly, and the chainsaw engine will give bluish fumes with the gas smell. An issue with compression rings will not immediately stop your chainsaw from starting, but it indicates a bigger and costly repair shortly. The common cause that begins this problem is running the chainsaw with less engine oil.

Solution: Replace the compression rings urgently. You may need professional help in this matter as you will need to open the engine head and then replace the rings.

Problem # 12: Clutch Pads

Broken clutch pads don’t allow power transfer from the crankshaft to the flywheel and prevent the chainsaw from starting.

Solution: The only solution is to replace the clutch plates.

How to avoid the above issues?

By following some simple things, you can avoid the above issues and keep your chainsaw in mint condition. If you follow the below-mentioned routine carefully and regularly, your chainsaw will start at the first attempt and will go a long way with you.

Never store a chainsaw with gas in it. Please turn off the chainsaw, empty the gas, and keep it running until it stops on its own. Store your chainsaw in a dry place.

Always service your chainsaw after 24-30 hours of usage. Follow the manufacturer’s directions in this regard.

Always use fresh and high-quality gas recommended by the company.

When you notice anything wrong with your chainsaw, please don’t use it until you get it sorted out. Be proactive than reactive.

Unable to Start a New Chainsaw?

If you cannot start a new chainsaw, the most important thing to do is read the manual. Some of the common issues that stop a new chainsaw from starting are listed below.

  • The fuel system is air-locked.
  • There is not enough gas in the fuel tank.
  • There is old gas in the tank.
  • A spark plug is not installed, or the plug wire is disconnected.
  • The primer bulb is not pressed or pressed too many times, resulting in a flooded engine.
  • You have mixed oil and gas in the wrong ratio.

What to do if an Electric or Battery-powered Chainsaw won’t start?

Electric or battery-powered chainsaws have their own needs and thus need maintenance a bit differently. If your corded chainsaw is not starting, check the power cable is not damaged, is properly plugged in, the starting button is working properly, and all the connections are made properly. For battery-operated saws, you need to check that batteries are properly inserted, adequately charged, and the power button is turned on. Electric chainsaws are complex machines, and you may need to have them inspected by a professional in case of an advanced problem.

Final Words

The above 12 solutions will solve your problem most of the time. However, it would help if you made some efforts to keep your chainsaw in a nice condition by spending some time on maintenance. A chainsaw makes your work easier by doing the toughest tasks for you; you must return some favor by taking care of it. We suggest that you always take necessary safety measures while working with a chainsaw.

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