adjusting triplex pump max pressure

[r7000]

Have a HF predator pressure washer, the big one... 4400psi 4.2gpm and 13hp predator gas engine.

The pump is AR RSV 4g44, and has an unloader so you can adjust pressure.

With the unloader all the way in, max pressure shown on a gauge located on the output connection of the pump and with no water flowing out the wand is ~3900 psi.

I want 4401 psi. How do you mess with a triplex pump with an unloader to increase max pressure to be [whatever] what you want?

 

[stretch5881]

Have a HF predator pressure washer, the big one... 4400psi 4.2gpm and 13hp predator gas engine.

The pump is AR RSV 4g44, and has an unloader so you can adjust pressure.

With the unloader all the way in, max pressure shown on a gauge located on the output connection of the pump and with no water flowing out the wand is ~3900 psi.

I want 4401 psi. How do you mess with a triplex pump with an unloader to increase max pressure to be [whatever] what you want?

Are you sure the engine is cranking 3600 rpm?
How many gallons per minute can your well feed the washer?

 

[EFSM]

I want 4401 psi. How do you mess with a triplex pump with an unloader to increase max pressure to be [whatever] what you want?

The easiest way is to put a smaller tip on your wand. The orifice size might be stamped into the side of the quick-connect fitting part or on the plastic end. Try going half a size smaller.

 

[Knots]

Have a HF predator pressure washer, the big one... 4400psi 4.2gpm and 13hp predator gas engine.

The pump is AR RSV 4g44, and has an unloader so you can adjust pressure.

With the unloader all the way in, max pressure shown on a gauge located on the output connection of the pump and with no water flowing out the wand is ~3900 psi.

I want 4401 psi. How do you mess with a triplex pump with an unloader to increase max pressure to be [whatever] what you want?

 

[r7000]

The easiest way is to put a smaller tip on your wand. The orifice size might be stamped into the side of the quick-connect fitting part or on the plastic end. Try going half a size smaller.

no

did you understand where I said "no water is flowing" ?

and same to the guy who asked about gpm that my "well" is feeding the pump.

 

[stretch5881]

no

did you understand where I said "no water is flowing" ?

and same to the guy who asked about gpm that my "well" is feeding the pump.

You didn't answer the engine rpm question.

 

[r7000]

You didn't answer the engine rpm question.

why do you say 3600 rpm?
no i do not know exactly what rpm the engine is reaching at full throttle, other than by ear it sounds acceptable.

and looking at triplex pumps, I see a max speed of 3450 rpm for some similar'ish triplex pump as the highest rpm i've found stated (i'm not finding any that say 3600, or 3800 rpm). I cannot find the max speed listed by AR specifically for RSV4g44 as they do not acknowledge it existing. And then many other pumps show 1750 as their max rpm. To my knowledge my pump is direct driven: https://manuals.harborfreight.com/manuals/71000-71999/71102-193175530295.pdf

 

[stretch5881]

The specs for the engine is 3600.

 

[RCBS]

Turning clockwise will increase pressure if the machine is capable. You need to get a guage setup that will couple in below your trigger handle. I worked on these things for a living for a few years. Always adjusted to spec when replacing an unloader, then backed off about 200psi which isn't felt in the wand. If you go too far, your pump will overpressure while in bypass and end up prematurely killing the unloader, at best.

The golden rule of pressure washers is that GPM > PSI in most applications.

What are you trying to do with 4k psi, I would ask?

 

[Boomer2230]

Smaller nozzle will boost your pressure, not much cleaning bonus from 3900 PSI to 4400 PSI.
Running at max pressure will blow out seals in the pump faster also.

If one of my past customers wanted 4000 PSI I would sell him one capable of 4500 PSI. Then turn it back to the 4000.

 

[r7000]

Smaller nozzle will boost your pressure, not much cleaning bonus from 3900 PSI to 4400 PSI.
Running at max pressure will blow out seals in the pump faster also.

If one of my past customers wanted 4000 PSI I would sell him one capable of 4500 PSI. Then turn it back to the 4000.

why is everyone chiming in about use a smaller nozzle?

HTF is the pump going to make more pressure with water flowing versus as I said when water is not flowing?

The pump makes at most high 3000's with the unloader turned all the way in for max pressure, and water not flowing! the rig is advertised as 4400 psi.

What am i trying to do with 4k psi... get what I paid for.

 

[EFSM]

I'm not certain that AR even makes a pump that's good for 4400 working PSI. That could be the greatness of horrible freight.

 

[r7000]

I'm not certain that AR even makes a pump that's good for 4400 working PSI. That could be the greatness of horrible freight.

your pic showng the 40hd-f40ez pump, where/who is saying that? what website? thanks.

my HF "4400psi" pressure washer also does not have easy start valves, if engine doesn't start on 2nd pull then you have to trigger the wand to release pressure otherwise you can't pull the rope starter on the engine.

 

[EFSM]

AR Triplex Pressure Washer Pump -AR RSV4G44

This triplex pressure washer pump is rated at 4000 PSI and has a 4.0 GPM. With a five-year warranty, rest assured that youre covered. Buy now and save!

www.pwoutlet.com

I know its a different model number, but that website claims it's the same thing. I definitely can't independently verify that.

 

[Boomer2230]

View attachment 432795

why is everyone chiming in about use a smaller nozzle?

HTF is the pump going to make more pressure with water flowing versus as I said when water is not flowing?

The pump makes at most high 3000's with the unloader turned all the way in for max pressure, and water not flowing! the rig is advertised as 4400 psi.

What am i trying to do with 4k psi... get what I paid for.

Water wears out the inside orifice of the nozzle opening the hole dropping the back pressure.
Your PW might have the wrong nozzle from factory.