Power Washer Vibrates Heavily Every Few Seconds

Hey everyone. I hope you and your families are all in good health and doing alright during these strange times.

I have a DeWalt 2.5 GPM power washer with a Honda GX200 engine. Model DXPW3425.

I’ve used this machine to run my business on for the past year and it has been reliable. Something it’s been doing for a long while is concerning me. When I hold down on the trigger, it runs fine. However, as soon as I let off the trigger it will wait a second or two and then shake very hard for about 2-3 seconds, the continue running as normal. Then, unless I press the trigger again, it will repeat that shaking maybe 10 seconds later for another 2-3 seconds, so on until I get back to just holding down the trigger.

It doesn’t affect the operating of the machinery (as far as I can tell) and it hasn’t given me any problems. I changed the engine oil fairly recently, don’t know if that matters for this. The shaking it does is so strong that it kind of fights against the bolts that hold it in place on my rig!

I want to resolve this issue with my machinery so that it doesn’t pose a problem on a job one day or give out on me entirely. Any insight into what parts might be causing this issue, or what to try is much appreciated.

You need to reset your unloader, sounds like it got out of adjustment.


Alright, I’ll definitely try that out to see if it gives me any luck. Thank you for the reply!

I would also check for leaks in all of the fittings and hoses.

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Could be the unloader. Try dialing it down so that it doesn’t violently release a ton of pressure when you are off the trigger. That might be the cause of the shaking I’m not sure though

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I didn’t know what to type into the search bar, but now that I’m looking up unloader issues I am starting to realize those slight leaks in the fittings right after my unloader might be a bigger issue than I thought.

Thanks so much for your reply, definitely gonna order some new fittings because when I started my business I wasn’t the best at rinsing after house washes so they’re probably looser from oxidation over time.


Sounds like a good idea, thanks for the input! I’m starting to see a theme in these responses I’m getting… LOL

Be safe!

The leaks are likely the problem. After so much water leaks out of the fittings it cycles the unloader for a split second and causes “water hammering” through the lines. It happens every ten seconds because that’s how long it takes for enough water to leak out to cause the unloader to cycle. Get those leaks taken care of and you should be good to go.


Insightful stuff, thanks a ton! Will definitely put this knowledge to good use.