The Murray snowblower uses various sizes of Briggs & Stratton engines. Briggs & Stratton recommends changing the oil in its engines every 25 hours of operation. The company also recommend using 5W-30 motor oil when changing the oil. This viscosity should meet most needs for the season. Looking from the handles forward, the oil drain plug will be on the left side of the engine.
Start the snowblower and allow the engine to run for five minutes. This will warm the oil, allowing it to drain faster. Stop the engine, remove the safety ignition key, and disconnect the spark plug wire from the spark plug.
Locate the oil drain plug on the left side of the engine near the left wheel. The drain plug will be more accessible if you remove the left wheel. Pull the klik pin that secures the wheel to the axle. Ask a friend to lift on the left side of the blower enough that you can slide the tire off the axle. Allow the blower to sit on the left axle.
Position a drain pan under the drain plug. Remove the plug by inserting the blade of a flat-head screwdriver between the notches on the plug. Turn the plug counterclockwise to remove the plug. You will also get more oil to drain from the crankcase with the tire off and the blower tilting to the left.
Place the oil plug back into the crankcase and twist the plug clockwise to secure the plug. Ask a friend to lift up on the left side of the blower while you slide the left tire over the axle. Insert the klik pin in the outer hole of the axle in front of the tire rim.
Wipe the area around the oil fill cap with a clean cloth. Turn the fill cap counterclockwise to remove it from the engine. The dipstick is mounted to the bottom of the fill cap.
Pour ¾ qt. of 5W-30 motor oil into the oil fill neck. Place the oil cap and dipstick into the oil fill neck and twist the cap secure. Remove the cap and check the oil level on the dipstick. Continue adding oil until the oil level reads full on the dipstick. Secure the oil fill cap to the engine. Plug the spark plug wire over the spark plug.