Okay now my pressure washer engine will quit as soon as I let go of the trigger on the wand. I understand when that happens that it is likely the unloader valve on the pump will need to be replaced. I've never done that before but am gonna give it a try. I took a few pictures just to ask here if indeed what I'm pointing to is the unloader valve. The pump brand and model is Annovi Reverberi RSV3630A. I suppose I will have to try to acquire the specific unloader valve for that make/model? Is it an easy change-out usually or will I probably have to remove the pump from the engine and mostly disassemble/reassemble the pump, etc? Any comments/advice appreciated.

 

Okay I found some answers to my own questions. I found a diagram of the pump here which shows the unloader valve (parts 1-15). And I took the valve out of the pump; looks pretty straighforward how to replace, just screw a new one in. And I found one for sale on ebay; looks like they cost at least 50 bucks or more depending on where you might buy it. I was just wondering if I took my old valve apart and looked at it whether I could see anything wrong with it, or maybe just work it back and forth and stick it back in and see if it'll start working again. Any comments appreciated.





Unloader for Annovi Reverberi RSV Pumps AR2280 2280 RSV Up to 3200 PSI | eBay

 

I disagree.

In my opinion...... if the engine runs fine until you pull the trigger then it's not the unloader valve. It's your carburetor starving the engine for gas. It may just take enriching the mixture slightly.

 

PJ,
Sorry my initial post here I typed the wrong info. The engine runs fine until I let go of the trigger.

Edit: If I could I'd edit my mistake. I no longer have that option available because too much time has passed since the post. Perhaps a moderator could edit that sentence in my first post here to read "Okay now my pressure washer engine will quit as soon as I let go of the trigger on the wand."

 

No problem.... I edited your first post per your request.

Based on this new info I agree with your diagnosis of the problem.

 

Here's a better view of the parts diagram at this link. Parts 1-15 consist together as the unloader valve assembly. I tried as I suggested I might in post #2 here and worked the valve back and forth manually after removing it and then installing it back into the machine but that didn't help. So I locked the trigger into the pulled position and could run the pressure washer that way, until such time as I can acquire a new valve or possibly repair the old one. http://www.pressureparts.com/mmDEV/PDF/AR/rsv-pumps.pdf

 

I was wondering if it'd be okay, on a temporary basis while waiting to acquire a new unloader valve, to just thread a plug into where the unloader valve would otherwise be threaded into, and just make sure to keep the wand gun trigger secured in the pulled position at all times (held with a string/strap or whatever) while starting and operating the washer, thereby just eliminating the malfunctioning valve from the system so I can at least keep working until I get that part. Or would that potentially somehow cause further harm to other pump components? Also I might mention another correction to my first post here; the model Anno Reverberi pump is 3G30 not 3630.

 

At the page at the following link if you click on "click to enlarge image(s)" you can see a close up of the unloader assembly and as well a detailed closeup of the parts breakdown within the assembly.
Unloader Assembly

I got to the point of disassembly as shown in the following photo but cannot see how to remove part #13 (plunger tip) so I can disassemble completely to inspect the remaining innards. That tip seems to be pressed tight onto the plunger. Any suggestions appreciated here.

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Just an update here: ordered a new unloader valve assembly and it got here today. installed it and the problem is gone.

 

I'm having a similar issue and have the same unloader..when I pulled it out, I also couldn't remove the "plunger tip", but I did notice that mine was pressed up against the "Piston guide" and I could pull it a little bit. On your pic I'm seeing a gap..were you able to "push" yours in? Also when receiving the new one, were you able to tell what was wrong with the one that was not working? Just looking to make sure mine is faulty before spending 50 bucks on a new one.. Any insight is appreciated!

 

Derf,
On my old unloader valve I can push the plunger tip all the way to where it will meet the piston guide but the plunger tip itself I cannot get to budge off the end of the piston to which it seems to be pressed on and no way that I know of to remove it. When I received the new one, the only difference I could tell was that the up/down action of the piston seemed maybe somewhat looser/easier but not really much. I would've liked to have been able to get that plunger tip off and so maybe have been able to disassemble the valve further to investigate to see if I could discern the problem and maybe just clean it or get a rebuild kit and see if I could fix it free or cheaper instead of having to buy the assembly which was rather spendy. I was reading that it is kind of typical for an unloader valve like this to "wear out" after a significant period of time (like anything else I suppose), but as far as what specifically caused the failure it remains a mystery to me. Perhaps there is something like a miniature pull-tool that could possibly be utilized to pull off that plunger tip, but the average-equipped diy-er isn't gonna have anything like that.

 

Sgull,
Thanks for the reply! I took apart the unloader this weekend and was able to get the tip off by unscrewing and then finally giving a good pull with needle nose pliers..I cleaned everything although the unloader looked to be in good shape, put it back together but still no pressure, so now I'm looking to get the pump replaced.

 

Derf,
When I get a chance (tomorrow) I'll try to simply unscrew the tip as you described. I would think then that I'll need to hold the the piston from turning with the tip as I unscrew the tip from it? Just grip the piston with pliers?

Also, because you mentioned you have the same unloader I assume your pump is Annovi Reverberi? I noticed there is some pretty good info available online in regard to rebuilding these pumps in the case you might consider going that route, rebuild kits available etc. Like here for example: http://www.arnorthamerica.com/manuals/rsv-om%200607.pdf Also some pretty decent explanatory videos on youtube in that regard. Thanks for the "tip" on the tip (pun intended).

 

I had no luck trying to unscrew the tip off. I tried using the method pictured below, holding the piston with needle-nose pliers and then trying to unscrew the tip with the wrench. Couldn't squeeze the needle-nose hard enough to keep the piston from turning along with the tip while trying to unscrew the tip from it.