RMW Pump Repair Video



Above is a RMW pump repair video from AR North America, the manufacturers of the pump.  They do a good job (as they should!) describing the repair of their pumps.  But I have gone thru it and added (what I think are) helpful notes.  I hope this helps you somewhat.

First note, this video shows how to repair a number of different issues – valves, water seals, unloader, chemical injector, and EZ start valve.  Not all of these repairs need to be made at the same time!  You pump may only have one issue that needs to be addressed.

If you want some printed steps on these repairs or some basic diagnostic info, you can find them here:


If you need to figure out what is wrong with your pump, give us a call!

Notes: (number in parentheses is the time on the video)
(0:25) – Discharge valves – you don’t need those fancy power tools, a regular old socket wrench works just fine!
(0:35) – Discharge valves – They are using reverse pliers to remove the valves (and they do help) but you can use needle nose pliers.  Note: the valves may come apart when you take them out.  That’s OK, they can get put back together.
[These notes are the same for the Inlet valves.]
(1:21) – Water seals – Chances are good that some of the black water seals will stay on the pistons.  Note: the hard, white plastic rings are bushings; these only need to be replaced if they are damaged – usually melted due to overheating of the pump.
(1:36) – Water seals – They use a pick to remove the seals, you can use a finger or a flat head screwdriver.
(1:58) – Inlet valves – Secure the valves by gently, yet firmly, pushing them down with something, anything that won’t damage the valve.  It should almost ‘pop’ into place.
(2:25) – Water seals – The flat side of the seals should be facing toward you.
(4:55) – Chemical Injector – When you remove the hose barb, be very careful!  The ball and spring inside have a tendency to fall out and disappear.

Pump Repair: Primary Diagnosis

So, your pressure washer pump is not working right and you’ve decided to fix it. Awesome! Let’s talk about how to diagnose the issue.

First, note exactly what is happening. I’m going to guess that you’ve lost pressure. But how much? Is it a partial loss (still have some pressure),total loss (same as if there was no pump), or a complete loss of water flow (no water at all is coming out of the spray gun).

So how do you figure that out? Crank up the pressure washer and pull the trigger. Note the water flow. Now turn off the engine and pull the trigger. What is the difference? If there is no difference, there is a complete loss of pressure from the pump. If there is a difference, then you only have a partial loss.

Why is this important? Well, these different scenarios mean different things are wrong with the pump. We will get into each one in future posts.

Now, you may also note other things wrong. Maybe there are some funny noises, vibrations, pulses, or the like going on. That will indicate other issues as well.

We will try to cover those things in the future. But for now, give us a call if you have questions.


Hey folks. You know how you’re supposed to save you work on a computer? You know, just in case something happens? Well, something happened. I lost all my blog posts. So I’ll be working to try to recreate some of what I have lost.

So. Backup you work!