The Karcher 2400 psi Power Washer is a gas-powered washer that uses oil to lubricate the motor. In the Owner's Manual, Karcher recommends that you change the oil after the first five hours of use, and again after every 50 hours of use. Your Karcher may vary from these times based on its age, however. The seals in a well-used Karcher will wear down and mix water with the oil, which will need to be changed. Fortunately, changing the oil in a Karcher Power Washer is a straightforward task. So long as you have an adjustable wrench and some plastic buckets, you can change the oil within half an hour.
Locate the oil tank on the Karcher 2400 psi Power Washer. The oil tank is below the motor on the side of the washer that the spray hose mounts to.
Find the bolt plug below the oil tank that the oil drains from.
Loosen the bolt plug from the oil tank using the adjustable wrench. Turn counterclockwise. Do not loosen completely.
Place a plastic bucket below the plug. Use a short bucket or cut a bucket to a short height, because there's only a few inches of room to place the bucket.
Take off the bolt plug and let the oil drain into the plastic bucket. Have a spare bucket nearby in case the bucket you're using fills before the oil tank empties.
Replace bolt plug. Tighten with one turn of the adjustable wrench, turning clockwise.
Remove the dipstick from the oil tank and place a funnel where the dipstick was.
Pour in replacement oil up to the bottom of the oil filler neck.
Take off funnel and replace the dipstick.