Step 1
Look the chain saw over, and clean any debris or stuck pieces of wood from all areas surrounding the chain. Sometimes a stuck chip of wood will keep the chain locked in place. Wipe it down with a rag. Use a screwdriver to help scrape oiled sawdust out of the nooks and crannies of a chain saw.
Step 2
Grab the chain, and ensure that it turns on the chain saw bar. Use gloves to avoid cuts.
Step 3
Check the safety lock mechanism. Verify it is not kicked in the lock position, which will keep the chain saw from operating properly. This bar shifts into position when pushed by the operator, as a matter of safety to cut the operation of the saw. It can also be accidentally pushed and shut the saw down.
Step 4
Verify the pull-cord is operational. This may require removing the cover and inspecting the cord. Remove the screws holding the cover in place over the pull-cord. Use care when removing the cover as the cord winds into a spring-loaded mechanism. When this fails, the chain saw will fail to operate or start. Replace the pull-cord mechanism if needed.
Step 5
Remove the spark plug and inspect it. Pull the spark plug wire, and use a ratchet and spark plug socket to remove and inspect the spark plug. A damaged or bent spark plug tip indicates a bigger problem with the engine requiring replacement or rebuild.
Step 6
Pull the starting cord on the chain saw. If after freeing up the pull-cord or replacing it, you find it operational, this also means the piston is moving freely inside the chain saw engine. If not, the engine requires a rebuild or replacement as the problem is internal to the engine.