It is recommended that you don’t drain gas from a lawn mower when storing for longer as this opens the tank for condensation. You are required to stabilize the remaining fuel and store your lawn mower in clean dry place. If you don’t do that, the fuel in the system will go bad and you will have problem starting your lawn mower.
Bad or old gas in a lawn mower need to be drained out before a fresh one is added. This can easily be done using a fuel siphon pump or by disconnecting the fuel line from the carburetor to let the gas drain out to a collecting pan.
CAUTION! Bad fuel can spew noxious fumes, therefore work in a well-ventilated area. Ensure you turn off your lawn mower and disconnect the spark plug wire. Petrol is highly flammable, there should be no any open flame near your working area.
How to Drain Gas from Lawn Mower – Steps
To drain fuel from your lawn mower, you’ll need a gasoline siphon hose, a rug and a collecting container like metal can or drain pan. Then follow the following steps.
- Park your lawn mower on a flat ground in a well-ventilated area. This will help the fuel to remain in one place in the tank for easier removal. Tipping your mower can direct fuel into other sections where it cannot easily be accessed.
- Disconnect the spark plugs wire to prevent the lawn mower from accidentally starting while you are draining the gas tank. Gasoline is also highly flammable and any single spark can start fire.
- If your lawn mower comes with a fuel line that runs from the gas tank to the carburetor then place the collecting container under the section and disconnect the fuel line so that fuel can drain out of the tank.
- For a lawn mower without fuel connector, open the fuel tank cap and insert a siphon hose down into the fuel and its other end into the collecting container placed on the ground next to the tank.
- Squeeze the bulb on the siphon hose multiple times until enough vacuum is created in the tube to start draining fuel from the tank.
- Once all the gas has been drained from the mower fuel tank, disconnect and clean your lawn mower carburetor using a carburetor cleaner to remove all traces of contaminated gasoline.
- Use a rug to wipe out any gasoline spills on the tank or other parts of the lawn mower
- Reassemble the carburetor back on the engine, refill the tank with fresh gas and start your lawn mower engine.
How to Stabilize Lawn Mower Fuel (for Storage)
Whether you are storing your lawn mower for winter or any period longer than 30 days, then you need to stabilize the fuel to protect the fuel system from corrosion, gumming up and clogging. This will give you an easy time starting your lawn mower when you take it out of storage.
A fuel stabilizer works for all types of fuel and effectively when the gas is fresh. So you may decide to run your lawn mower engine until all the fuel is burnt or drain the remaining fuel from the mower tank. Once you have an empty gas tank, then you can add fresh stabilized gas.
A proper mixing ratio of fuel stabilizer to gasoline is always provided on the fuel stabilizer label. Some brands recommend adding 1 ounce of fuel stabilizer to 1 gallon of fresh gasoline, while others recommend 1 ounce of stabilizer to 2.5 gallons of fresh gasoline.
Once you have chosen your favorite brand of fuel stabilizer, fill your mower’s tank to 95% full capacity with a fresh stabilized fuel. The remaining 5% helps the fuel to expand comfortably in warm weather without spilling. Run the engine so that the stabilized fuel can flow into the carburetor and entire fuel system.
According to Briggs and Stratton, the leader in manufacture of small engines and lawn mower parts, using fuel stabilizer eliminates the need to drain fuel prior to storage of your lawn mower by keeping fuel fresh for up to 24 months.
Therefore drain gasoline from your lawn mower only if you are adding stabilized fuel for storage or if the current fuel has gone bad and you want to refill with a fresh one.