Adjust power washer unloader valve - delayed disengagement after pump fluid replacement.

Joined
Feb 19, 2009
Messages
1,482
Location
The Woods of NY
I have this 3100 PSI Honda GVC190 pressure washer. Replaced the carb when I first picked it up in the spring and have done a couple Synthetic 10W30 oil changes and a plug / filter. It runs great, BUT one thing I never did replace is the pump fluid. This pump actually has a black plug midway up the pump that you can remove dump out 1.2 ounces of fluid and replace. So I did. used OEM pump fluid and changed it about 4 times using it each time for a few minutes to circulate the pump fluid. The initial change the fluid was pitch black. By the 4th change it's still had a little honey color to it so I figured that was enough as I'll do it again in the spring.

I was using it to power wash the car the next day and noticed when I release the wand the pump is still "engaged" for around 1 sec after. The engine does not sound different as in more stress it sounds normal load but the kick off for the pump is not instantaneous like it was initially. Revving the engine or slowing it down by holding throttle makes zero difference in the delay.

Could I have to adjust the unloader valve for some reason? Maybe the pump is working a little more efficiently and it's affecting the cut off of the unloader valve pressure? When I'm actively using the power washer the pressure is instantaneous and does not fluctuate nor vibrate it's always a continuous steady perfect stream of pressure. as safeguards i always prime the pump of air before start plus use the pump lubrication liquid that you push through the cold water intake. (Name is escaping me ATM lol)

So does this sound like a unloader valve mis adjustment? I wanted to ask here before I start adjusting things and get your opinions of this subject. 🙏

Thanks. :D
 
Is the unloader adjustable? If so have you tried adjusting it to see if anything changes?
As long as the pressure seems normal and the valve is still unloading I wouldn’t worry about it.
 
Yes, it could need adjustment. There are youtube videos showing how to do it, the way they are adjusted depends on the design of the pump you have. The pump saver fluid is good to use, and many times sticking unloaders are caused by the water contaminants and build-up.
 
If it works and doesn't kill the engine use it till it dies. Chances are it will either come out of it or break. If you start messing with things there is a good chance it will get worse or work better but break anyways.
 
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