To service a Kranzle K7 or K10 pressure washer, you will need to perform the following steps:

1. Drain the water from the system: Start by attaching a hose to the drain valve on the pressure washer. Open the valve and allow the water to drain out until the system is empty. 

2. Flush the system: Once the system is empty, attach a garden hose to the inlet valve on the pressure washer. Turn on the water and let it run through the system for a few minutes to flush out any debris or contaminants that may have accumulated inside.

3. Replace the inlet filter: The inlet filter is located on the inlet valve and is responsible for filtering out any contaminants from the water before it enters the system. Remove the old filter and replace it with a new one. 

4. Check and replace the seals: Inspect the seals on the pump and any other moving parts for signs of wear or damage. If the seals are worn or damaged, they should be replaced to ensure proper operation of the pressure washer.

5. Lubricate the moving parts: Use a high-quality silicone grease to lubricate the moving parts of the pressure washer, including the pump, hose connections, and any other areas that may be prone to friction. 

now to change the oil!

To change the oil on a Kranzle K7 pressure washer, you will need to follow these steps:

1. Locate the oil drain plug: The oil drain plug is located on the bottom of the pressure washer, near the base of the pump unit.

2. Place a drain pan underneath the pressure washer: Position a drain pan underneath the pressure washer to catch the old oil as it drains out. You will need a container larger than 1L. 

3. remove the red oil filler cap on the top of the pump unit using a spanner or socket. This is plastic so do not use excessive force. 
   
   

4. Remove the oil drain plug: Using a wrench or socket, loosen and remove the oil drain plug. Allow the old oil to drain out completely. Inspect the magnetic drain plug for debris and clean with a rag.

5. Remove the clear plastic oil viewer on the side of the machine  be careful when removing not to damage the plastic  clean and replace this, again being very careful not to over tighten. 

6. Add new oil: Once the old oil has drained out and the drain plug replaced, add new oil to the pressure washer. Use synthetic 10w 40 motor oil  and slowly fill the machine from the top, fill until the oil level is visible to the top of the viewing window  adding more than this could damage the machine.

7. Run the machine: Finally, check the oil level using the oil level indicator on the pressure washer. Add more oil as needed until the level is at the recommended level.

By following these steps, you can easily change the oil on your Kranzle K7 and K10 pressure washer. It is important to follow the manufacturer's recommendations for oil type and change intervals to ensure that your pressure washer is operating at its best.