What to do if your chainsaw won’t stay running?

Start by checking the basics such as Fuel, Switches and Spark Plugs and making adjustments. It can be as simple a solution as that. If that doesn’t resolve the problem, the issue may lie with the carburetor – which may require a visit to the repair shop.

Here are the basic issues and troubleshooting steps:

There might not be enough Gas – If you haven’t used it for quite some time, the gas may have evaporated. Make sure the gas tank is at least half full.

The gas might be old – If unused for a long time, the volatile components of the gas will evaporate and it will not ignite. If you are not sure about the age of the fuel, empty the gas tank and refill with new gas. Fuel is only good for 8 weeks from the day you purchased it.

Fuel Line and Fuel Filter might be blocked or damaged – If the Fuel Line and Fuel Filter is damaged, split or blocked, the chainsaw will not get enough fuel. Dip the filter in gas and see if it will freely run through the other side. If it doesn’t, replace it.

Diaphragm might be sticky from old gas – The diaphragm goes bad over time. If you find that it’s sticky, buy a rebuild kit or replace it.

Spark Plug might be old – If the spark plugs are dirty or corroded, clean it with a steel brush or replace it altogether.

Idle ports may be plugged or blocked – This is the small ports in the carburetor where the fuel passes through when in idle. Give it a good cleaning to remove any clogging or blockage.

Clogged Air Filter – Put the air filter up against a bright light and check if there are dark areas deep in the filter. Clean the filter or buy a new one.

Vent in the Fuel Cap is plugged – If the vents in the fuel caps are clogged the fuel becomes vacuum locked. Check the cap and clean it or replace.

High-Low adjustments screws may need calibrating – If you have these screws in your chainsaw, adjust them by turning both screws clockwise until you reach the end – gently. Do not force or damage! Bring the saw to full throttle. Starting with the High Speed screw, turn it up counter clockwise until the chainsaw starts sounding rough and bucking. You can determine this from the vibration. Remember the position. Turn the screw clockwise until the chainsaw misbehaves again. Adjust the screw halfway between these two positions. For the Low Speed screw, repeat the procedure in idle.

If you’ve checked all the possible problems and corrected them and your chainsaw still won’t stay running – it might be time to bring it to the service center for a carburetor check-up.

What to do if your chainsaw won’t stay running?

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