RYOBI Petrol Chainsaw hard to start or doesn’t run correctly

There are a few reasons that may cause a petrol chainsaw engine to be difficult to start or run roughly.

Make sure you're starting the chainsaw correctly:

• Engage the chain brake
• Press the primer bulb 10 times
• Pull the choke out to full
• Pull the starter cord until the engine sounds like it is about to start but no more than 5 times
• Push the choke in to half
• Pull starter cord until unit starts
• Squeeze and release the trigger a few times
• Let the unit sit on idle for 15-30 seconds before use.

Flooded Engine

• A flooded engine will prevent a chainsaw from starting.
• A flooded engine means there is excessive fuel pumped into the engine which has displaced the oxygen needed to start the chainsaw.
• If you have attempted to start the engine unsuccessfully there is a chance your engine is flooded. Let your chainsaw sit flat for 15-20 minutes before attempting to start it again, following the correct starting procedure mentioned above.

Stale Fuel

• A common cause is stale fuel. Fuel starts to lose its volatility after 30 days.
• This will affect the ignition of an engine. Replace your fuel with fresh fuel and see if this helps. You can also buy fuel stabiliser that will keep fuel fresh for 12months. You can purchase this from your local Bunnings store. 

Incorrect fuel mixture

• Incorrect fuel mixture can prevent the chainsaw from starting or cause it to run roughly.
• Make sure you are using the correct fuel mixture with your chainsaw. Ryobi chainsaws run off a 50:1 ratio, this means 50 parts unleaded fuel to 1 part 2-stroke oil.

Leaving choke on

• Leaving the choke on will cause your chainsaw to run roughly and shut off.
• Once your chainsaw has started make sure the choke is in the run position. Be sure to follow the correct chainsaw starting procedure.

Spark plug lead disconnection

• The spark plug lead can sometimes disconnect from the spark plug after being knocked or transported.
• Make sure the spark plug lead is connected properly.

Check chain is tensioned correctly

• Make sure the chain is tensioned correctly.
• If the chain is over tensioned this can stop the chain from spinning as it should.

Check the chain brake isn't engaged

• If the chain brake is engaged the chainsaw chain will not spin.
• On a battery chainsaw this will stop the unit from starting.
• Make sure the chain brake is in the disengaged position before starting.

Make sure the correct chain is used

• If you have replaced the chain, make sure the new chain matches the specifications for your specific chainsaw, these specifications can be found in the manual for your chainsaw.

Make sure the chain is seated correctly

• Make sure the chain is seated correctly on the bar and sprocket, if this is not seated correctly it will not function correctly and can be dangerous.

Dirty air filter or spark plug

• Another common cause of a hard to start motor or a roughly running motor is a dirty air filter or spark plug.
• These parts should be inspected regularly and do require replacement throughout the life of a chainsaw.
• To find and order the correct replacement filters and spark plugs for your unit contact your local Bunnings Special Orders desk and quote them your chainsaw’s model number.
• For instructions on how to check and clean your air filter, refer to the video instructions: