If you have noticed pulsating flow when the pump is running. This article will explain how the valves work. Then I’ll go over how to replace them. Lastly, I’ll review some possible causes of failure and preventative measures. This might be more of a technical support article but I think you’ll enjoy learning about your Kranzle pump and realize it’s quite simple. Taking apart your pressure washer and seeing all the parts is a great way to appreciate the quality and engineering put into a Kranzle.
Here are the tools you will need for this task: 13mm wrench, 22mm wrench, pick tool
If you have the 1122 model, the first thing you will want to do is remove the hose reel. This will give you access to the valves. Here is a support article on how to do this: How to remove the Kranzle K1122TSS Hose Reel
How the valves work.
There are five parts to the valve:
- Metal faceplate (seat ring)
- Plastic cage housing
- Valve plug
These five parts are crucial to the construction of the valve to allow them to function properly. They are able to make a water-tight seal even under the high pressures of the pump. One of the major design functions that help achieve this is that they are directional. This means water can only pass in one direction. They are pointed in a specific direction so that water only passes one way through the pump.
The plunger cycles back and forth like a syringe creating suction and pressure. There is a valve on the inlet and outlet of each plunger. Only one of these valves is open at a time. If the plunger cycles back and creates a suction the inlet valve opens and the outlet closes. The inverse happens when the plunger cycles forward and creates pressure.
How to Replace the Valves
To remove the valves, start with the valve cap with the gauge. You won’t need to remove the gauge itself. If you want to remove the gauge, here is a link to the support article. This cap uses a 22mm open end wrench. The rest of the caps use a 13 mm wrench/socket. Once the cap is off you will have access to the valves. If you can’t pull them out by hand, you can reach them easily with a pair of needle nose pliers.
You may notice the valves are different colors like green and red. This is normal and both will work on the 1122, 1622, and 1322
The last thing to remove is the o-rings. This is where the pick tool comes into play. There are o-rings in the base of the bottom of each hole that the valve sits on. There are also o-rings in the caps. If you're replacing the o-rings, don’t worry about damaging them. However, if you're just inspecting them, I would be careful not to tear the o-ring.
Now that the old components are out, we can begin assembly. The first piece to go in is the o-rings. There are twelve o-rings for the caps and the inside of the pump. All the o-rings are the same so it doesn’t matter which ones go in the pump or on the cap.
You can use the valve to help seat the o-ring in the pump. Double check to make sure the o-ring and valve are seated properly. If not installed correctly, the plastic valve cage can get crushed and the pump won’t build pressure.
(Ex. improperly installed valve)
Remember the metal faceplate of the valve goes down in the hole. Finally, the caps can be tightened down. To tighten the caps, do an initial torque and then come back and do a second torque.
If you are inspecting the valves instead of replacing them, there is a test you can do to ensure the valve is functioning properly. It’s called the suction test. Place the metal faceplate to your lips and try to suck air through the valve. If the valve is working properly, no air should pass through. This test checks to ensure a few of the components are working properly. One of the things it checks is the spring tension behind the valve. Another is there is no debris obstructing the valve from sealing.
(Ex. obstructed valve)
The last step is to run the unit to see if the problem is fixed.
Causes of Failure
Here are a few reasons a valve can fail and tips to avoid damaging them in the first place.
- Debris from the garden hose. If the garden hose is laying on the ground outside, bugs can crawl inside the hose. When the hose gets connected to the pressure washer, the debris can clog the valves. I recommend flushing your garden hose before attaching it to the pump.
- Extreme temperatures can affect the o-rings. The materials can degrade and lose their functionality if exposed to extreme temperatures. One example is freezing temperatures or using hot water.
- One way to preserve the life of your valves and o-rings is by winterizing your pressure washer. Here is an article on how to do this: How to Winterize your Pressure Washer
Now your Kranzle has fresh valves and smooth pressure. If you take anything away from this article, I hope you got familiarized with the terminology of the different parts. This was a more technical support article but I hope you enjoyed learning about your Kranzle pump and realize it’s quite simple. I think taking apart your pressure washer and seeing all the parts is a great way to appreciate the quality and engineering put into a Kranzle.