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Daniel H

Gallons per minute

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How much pressure do you need? I have a 10 gpm pump on 13 horse Honda.

Not much really, I just like water volume more than pressure...

I have 2 engines in the basement Im going to build a skid out of one and a cold water out of other... and I want to make them dual wand machinces

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I have a 16 hp Briggs that flow 8gpm all day long. You sacrifice pressure for volume. you could 50 gpm with a 16hp if you didn't care about pressure. Think about a trash pump.

William, what did the larger pump bring your psi down to?

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William, what did the larger pump bring your psi down to?

Not sure, I have never got around to buying a pressure gauge. By the math I would say about 1500 psi. All of my other machines are 25hp kohlers but I didn't want this one to go to waste when I cut the burner off of it so I put a 8gpm udor on it and it has been running for a few years now.

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About as much as you want!

GPM x PSI divided by 1100.

1 gpm x 20,000 psi divided by 1100 = 18.18 HP Required

100 gpm x 200 psi divided by 1100 = 18.18 HP Required

and so on....

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About as much as you want!

GPM x PSI divided by 1100.

1 gpm x 20,000 psi divided by 1100 = 18.18 HP Required

100 gpm x 200 psi divided by 1100 = 18.18 HP Required

and so on....

Awesome Ive been trying to find the math on that, to upgrade my current setup

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Some engines are a little stronger than others…

We like the Vanguard engines for reliability, plus they are strong by comparison to others…

We sell more 5gpm 4000 psi pumps for the 16hp engines than any other combination..

They run great, with sweet work-speed…

5 gpm brings great workspeed in rinsing action, without wasting water.

Also, 4000 psi is best on gum, and it brings a 21 to 24” surface cleaner “to life”.

With a turbo nozzle, graffiti goes away with less chemical.

If you spring for the 18hp motor, use the extra for long-term-low-cost..

5@ 4000 is fine, so let it run a little cooler.

The horsepower formula above, is good for gas engines, just remember not all engines “put out” at the same rating… remember that 4@4000 on a Honda 13 that never really put out the 4000 psi !?!

Get a pressure gauge rated such that you read the middle-third of the scale for accuracy…

Running at 4000 psi, get a 6000 psi gauge.

Call for more, we’re glad to help, and have the experience.

Jerry McMillen

President, Cleaning System Specialists, Inc. jerry@pressurewasher.net

dba PressureWasher.net call 800-400-Clean (2532)

10821 Airport Drive El Cajon, Calif. 92020 office 619-448-8111

manufacturers of… BullDogPro Industrial Water Blasters

Sirocco Reclaim Systems, and the VacuBerm

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You just have to remember that just because the manufacturer puts a 4 GPM @ 4000 PSI pump or a 5 GPM 4000 PSI Pump on a machine that doesn’t mean you will be able to obtain that spec.

It may sound good but it just won't happen.

Example: Using the math below - 4 @ 4000 requires 14.5 hp but you see them being advertised all day everywhere on a 13 HP Honda. And 5 @ 4000 requires 18.18 HP but you see them advertising that spec on a 16 HP Briggs.

It's just not true!

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You just have to remember that just because the manufacturer puts a 4 GPM @ 4000 PSI pump or a 5 GPM 4000 PSI Pump on a machine that doesn’t mean you will be able to obtain that spec.

It may sound good but it just won't happen.

Example: Using the math below - 4 @ 4000 requires 14.5 hp but you see them being advertised all day everywhere on a 13 HP Honda. And 5 @ 4000 requires 18.18 HP but you see them advertising that spec on a 16 HP Briggs.

It's just not true!

Are all pumps to that standard or is there a variation between General, Anno Reverbi and the other brands? Does is make a difference if the pump is a rooler pump or piston pump?

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I have a 12gpm run off of a 18hp vanguard.

Showoff! lol I'm guessing that the pump costs more than the engine! I converted my direct drive 4/3500 to 5.5/2600 gear drive. GPM's rule!

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Showoff! lol I'm guessing that the pump costs more than the engine! I converted my direct drive 4/3500 to 5.5/2600 gear drive. GPM's rule!

haha. I love that machine. I hardly ever use my Landa anymore except for when I need hot water. I picked the setup off of CL for 800 bucks. Its amazing what higher gpms means for our line of work. I am definately getting popeye arms holding on to the wand. And the surface cleaner helicopters up so I had to install a weight on it to keep from flying.

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John Allison (Homer) brings up an important point,

so let's get back to the original question...

"What is the most gpm pump I can put on a 16 or 18 hp Briggs? "

some engines put out less than what they are rated for, as you cannot "get" the

expected performance, like the 13hp honda that won't do the 4 @ 4000.

But, that 16hp Vanguard can do 5 @ 4000 psi... very nicely.

..so the Vanguard is strong, but there is a sacrifice... heat dissipation, and wear..

The most major change in expectation on the equipment in this industry in the past 25 years,

is performance for the dollar.. If you want to get 10 years out of that 16hp Briggs, don't use over 16hp, but you sacrifice potential workspeed... if you can make an additional $10,000. more in the next few years by throwing away an extra $1200 motor, your accountant will tell you, burn it up !... the buyer makes the decision. Take care of your equipment, give it every chance at long-term-low-cost, and if 5 gpm 4000 psi kicks-a$$ on workspeed, set it up. But you'd better do the PM,

or you'll be licking your own wounds.

I've sold MANY direct drive 16hp 5 @ 4000's.

I've also recommended the belt drive versions for lower repair cost,

but paying the difference, is still up to the customer.

None of us manufactures can make you buy the more expensive version,

but I feel we should provide the BEST reliability we can for your investment..

We set 'em up for reliability, and serviceability, but the user lives with the results of his purchase.

So, as you choose a combination of GPM and pressure..

You decide how hard you want to push luck. Eh?

I recommend, 5 @ 4000, 5.5 @ 3500, 6 @ 3000, 7 @ 2500, or 8 @ 2000

as long as it's plumbed for "the perfect water supply", with a "high-volume bypass",

and buy synthetic oil for ALL you engines.. they run cooler.

Jerry McMillen

President, Cleaning System Specialists, Inc. jerry@pressurewasher.net

dba PressureWasher.net call 800-400-Clean (2532)

10821 Airport Drive El Cajon, Calif. 92020 office 619-448-8111

manufacturers of… BullDogPro Industrial Water Blasters

Sirocco Reclaim Systems, and the VacuBerm

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