Water stops flowing when engine turns on

Water flows through the pressure washer pump just fine when the engine is off, but as soon as the engine turns on, water stops flowing out of the pump. What is the cause of this? I suspect the pump may have gone out, but if anyone has experienced this before, I’d like to know what you learned so as to inform my next steps.

This is on a Troy-Bilt 2600 PSI 2.3 GPM pressure washer from Lowe’s, model 020415. It has a Honda GCV 160 engine and an AR model RMW 2.2G24 pump. According to the reviews on the Lowe’s website, this model is notorious for having the pump go out after only a small amount of use.

The machine seemed to be working fine until the other day. I turned it on and was using it. Then, all of a sudden the engine turned off on its own. It turned it back on and 1-2 minutes later it turned off again. I repeated this several times, with the engine seeming to just turn off by itself. Finally, while the engine was still running, water stopped flowing. I turned off the engine and water started flowing again. The water was now very hot. This is not a hot water power washer.

I tested the garden hose by itself. It was working fine. Then I tested the machine with the pressure hose disconnected and water flowing directly out of the pump. Water flowed through while the engine was off, but as soon as I started the engine, the water stopped flowing. When I turned the engine off and water started flowing again, the water was warm.

I really think this is a pump issue and not an engine issue. What specifically in the pump is causing this? Is it possible that a single component of the pump needs to replaced, or will an entirely new pump be required? Since the pumps on this model of pressure washer are notoriously cheap, is there another model that is compatible with this machine that will last longer? How do I know if a given pump is compatible with the rest of the pressure washer machine?

Thanks for your help!





There are times in life when ‘the universe’ does something to tell you to change what you’re doing. This is your signal to upgrade your homeowner machine.

Thanks for your reply.

I already have a 13hp 4500 PSI 4 GPM pressure washer for serious work. A friend gave the little Troy-Bilt to me. I like having the Troy-Bilt around mainly because it’s so much easier to move around and set up for small jobs like washing cars. I was trying to rinse off my truck when it stopped working. Lot’s of people will use a little electric pressure washer for cars, but as a light duty pressure washer, this is just what I have laying around. I could throw it out, but it would seem like a waste of a good Honda engine.

I have a friend who would have been happy to build a home made go cart with the engine, but he moved out of town and that’s not my area of expertise. I’d just like to get it working again so I have a car rinser that’s not as cumbersome to get out as the 13hp one.

pump. Those things require you to be on the gun all the time, can’t recycle the water and just sits in there heating up. Disposable unit, they sell them by the hundreds every year.

You can probably find a new, cheap, Chinese pump for $50 or you can spend about $100-150 and get an electric ryobi to wash your car.

Sell it with the caveat the pump is bad, pick up another used homeowner unit.