Pressure washer problems

[Joe A M]

Hi, I have a gas powered pressure washer that the gun broke on . I bought a new gun with the same pressure rating from Northern tool. Now with the new gun I have to hold the trigger on to start the washer ( to much back pressure to pull the starter rope otherwise). Then as long as I have the trigger pulled & spraying it works fine, but as soon as I release the trigger to stop spraying it kills the motor everytime. Is there some kind of by pass or check valve or something that may be broken? I don't understand why it kills the motor now but never did before I replaced the gun.
Thanks for any help anyone can offer.

[Robert Adams]

Yup the bypass valve in the pump is stuck closed. The fix depends on the type of pump. It has probably just rusted or gunked stuck and disassembly and cleaning will do it.

[Joe A M]

Thanks, sounds like what probably happened. It sat for 2 yrs with out being used. I don't know what type of pump it is. All I know is I bought it from Home Depot about 9 or 10 years ago & it has a Honda motor. it probably only has about 5 or 6 hours of use. I would like to get it fixed though and not sure where to turn to.

[Mandrake]

As Robert mentioned it is likely the bypass (a.k.a. unloader valve).

Remove the pump, disassemble as much as you can and clean it out.

[Joe A M]

Ok so I finally got time to take the unloader valve off my pressure washer.
it was frozen in place. So I sprayed it down with liquid wrench let it soak awhile then i was able to move it in & out with a pliers but it still seems stiff to move in & out. I haven't had time to put it back together & try it yet as were having cold rainy weather.
Now the next problem I have is I wan't sure how to take it apart & I took the bottom off the unloader it had a large spring in it & seems to be adjustable. How do I know how tight to put it back on or how to adjust it back to where it should be.? I don't have any way to test it's pressure.

[Joe A M]

Thanks for the advice on the unloader valve. I finally got around to cleaning it up & lubricating it & putting it back together. I reinstalled it today & tried it out and it works good again. I never would have figured it out on my own.

[BobbtheEE]

Joe, I had that problem with mine a few years ago. On the advice of a fellow that repairs them, I started using those little pressurized cans of pump anti freeze/lubricant when I plan to store it for any length of time. It screws into the water inlet fitting and is dispensed through the pump lubricating the various parts. So far so good. I get it at one of the big box stores.

[daddo]

BobbtheEE said:

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Joe, I had that problem with mine a few years ago. On the advice of a fellow that repairs them, I started using those little pressurized cans of pump anti freeze/lubricant when I plan to store it for any length of time. It screws into the water inlet fitting and is dispensed through the pump lubricating the various parts. So far so good. I get it at one of the big box stores.

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Good to know.
Mine gets stuck once in a while. I hit the spray trigger a few times to get it loose. Someday that won't work.