Battery chainsaw stopped working because of a weak battery, a faulty charger, or a damaged chainsaw.

There are many reasons why your chainsaw might not start. Here are a few
The chain brake is engaged. Make sure the chain brake is disengaged before trying to start the chainsaw.
The chainsaw is out of gas. Check the fuel level and add gas if necessary.
The spark plug is fouled. Clean or replace the spark plug.
The carburetor is dirty. Clean the carburetor.
The air filter is dirty. Clean the air filter.

Incorrect chain tension, worn or damaged bar or chain, loose nuts, or a dull chain can all cause a chainsaw chain to keep coming off.

Chain saw won’t start because of no spark, no fuel, or bad compression. Check spark plug, fuel, and air filter.

Chainsaw won’t stay running
Possible causes
Low oil level
Spark plug not firing
Carburetor not adjusted correctly

Chain keeps coming off chainsaw because of loose or worn-out chain, bar nuts too tight, bar rails bent or damaged, or incorrect chain type.

Incorrect chain tension, worn or damaged chain, or a loose bar can cause a chainsaw chain to keep coming loose.

Incorrect chain tension, dull or damaged chain, worn or damaged bar, loose bar nuts, or a worn sprocket can cause a chainsaw chain to keep coming off.

Chain keeps coming off chainsaw? Check chain tension, bar nuts, and guide bar alignment.

Chain keeps falling off chainsaw? Check for a loose or missing chain tensioner, damaged or worn chain links, or a bar that is bent or out of alignment.