The unloader is as he stated.

Sorry for the large photo. But it shows good detail.

Start by checking the screen in part A. Circled in red to the right.

Then move on to parts B,C,D,E and F.
The small boxes at the bottom shows in detail how each of these parts are assembled. I highly suggest disassembling one at a time to clean and inspect. When reassembling the parts. Lube the rubber with baby oil or such light oil before reinstalling them.

The photo is fairly large and it may help to save it to your photos and then use the program to enlarge the photo to show better details.

Thanks hippy. Forgot to mention, before starting and hooking up hoses, I first checked the screen (part A) and then ran water through high pressure outlet (part B). So now that you've confirmed the 'unloader' I will move on to the others. Seems many people in the Karcher post were recommending to lube with silicone plumber's grease as it's supposed to offer more water resistant properties vs. other lubes. And the jpg is much appreciated; these eyes aren't getting any younger, lol. Hope to post a follow-up success story in the next day or two.

UPDATE: (1) Found a small chunk of plastic in compartment when removing Part C (about half the size of a grain of rice); also, Part C was missing O-ring. (2) Found two out of the three plastic *check valves* in base of well under Part D to be chewed up. Possibly this is what was found in Part C??? With very low hours and At this point, I am underwhelmed with the B&S pump/product. Sticker on bottom of pump says, "Made in P.R.C." (but isn't everything?) My local Costco only carries Simpson MSV3024 for $299; amazon gives it a 3-star rating. Can anyone recommend a higher quality residential washer for low use (2x yr.)?