Gravity Fed Simpson Pressure Washer

Mike_Sabol_314
Edited Date/Time 7/3/2021 9:55pm
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work.

It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM Gas Pressure Washer with a Honda motor. The book says minimum 20 psi input water pressure and if you do the math you only get 16-17 psi with a tank in the back of a pickup truck.

https://www.tractorsupply.com/tsc/product/simpson-h326-ms60773-2800-psi…

I’m hoping someone can verify gravity fed water works with this pressure washer.

Thanks!

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tprice07
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tprice07 1/8/2019 7:06am
1/8/2019 7:06am
Mike_Sabol_314 wrote:
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work. It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM...
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work.

It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM Gas Pressure Washer with a Honda motor. The book says minimum 20 psi input water pressure and if you do the math you only get 16-17 psi with a tank in the back of a pickup truck.

https://www.tractorsupply.com/tsc/product/simpson-h326-ms60773-2800-psi…

I’m hoping someone can verify gravity fed water works with this pressure washer.

Thanks!

I don't know much about those but this is what I have: Powerhorse Power Washer

It has lasted me about 3 years now and I figure if the pump craps out I have a few more options to upgrade the pump to something a little better since it has the horizontal shaft.
mxtech1
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mxtech1 1/8/2019 7:22am
1/8/2019 7:22am
You need around 20 PSI of water pressure to open the check valve on the pump input side.

In my experience, gravity feeding a pressure washer from a barrel in the back doesn't work because you cannot generate enough pressure to force the check valve open.

It is a simple modification to open up the pump on the pressure washer and remove the check valve. This will allow the pressure washer to work properly even if the pressure is less than 20 psi. You will have plenty of water flow as long as you use a decent diameter supply hose from the barrel to the washer.
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Monk
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Monk 1/8/2019 7:32am
1/8/2019 7:32am
No idea about this particular setup you're asking about. But I have a commercial grade 3300psi Honda Pressure Washer. A project I did years ago required me to mount a 250 gallon tank into the back of my 1-ton and pressure wash salt storage sheds. It was 100% gravity feed and worked awesome, even using a 150ft line. I don't know if a rain barrel can create enough pressure though.
lapper
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lapper 1/8/2019 8:12am
1/8/2019 8:12am
Assuming you are using plastic 55 gal barrel for your water source... My barrel is mounted on a 4 wheeled wagon. I can roll it away from my pit area or refill it without moving my rig. I use it at basically ground level. I tapped a schrader valve (valve stem) from and old inner tube in the threaded bung plug. Pressurize the barrel with an air compressor, tank or hand pump. Obviously you want to keep the air pressure as low as possible.
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526
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526 1/8/2019 8:33am
1/8/2019 8:33am
Mike_Sabol_314 wrote:
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work. It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM...
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work.

It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM Gas Pressure Washer with a Honda motor. The book says minimum 20 psi input water pressure and if you do the math you only get 16-17 psi with a tank in the back of a pickup truck.

https://www.tractorsupply.com/tsc/product/simpson-h326-ms60773-2800-psi…

I’m hoping someone can verify gravity fed water works with this pressure washer.

Thanks!

Have this exact unit and gravity feed off a barrel and it works perfect.
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Derek Harris 1/8/2019 9:32am
1/8/2019 9:32am
You can buy a cheap electric transfer pump and power it with 12 volts - and solve the issue a little.

Or as stated remove check valve.
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ns503
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ns503 4/16/2020 5:22pm
4/16/2020 5:22pm
mxtech1 wrote:
You need around 20 PSI of water pressure to open the check valve on the pump input side. In my experience, gravity feeding a pressure washer...
You need around 20 PSI of water pressure to open the check valve on the pump input side.

In my experience, gravity feeding a pressure washer from a barrel in the back doesn't work because you cannot generate enough pressure to force the check valve open.

It is a simple modification to open up the pump on the pressure washer and remove the check valve. This will allow the pressure washer to work properly even if the pressure is less than 20 psi. You will have plenty of water flow as long as you use a decent diameter supply hose from the barrel to the washer.
Old thread. But I was googling an issue and found this.

Can someone elaborate on removing this check valve? Just got a Simoniz washer with Kohler engine and Himore PW26 pump. Works great but severely disappointed it needs like 30 psi inlet pressure to work. Want to feed it off a 700 gallon tank, washer below tank. Seems these pumps have multiple check valves.
Jbulz
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Jbulz 4/17/2020 7:09am
4/17/2020 7:09am
Install lift kit in your truck = increased supply pressure from the barrel being higher up!

Now I get why all the motobros do it Grinning
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Rick Amatuzio 4/17/2020 7:55am
4/17/2020 7:55am
You guys are high. I’ve gravity fed from a drum 18” off the ground my whole life at the track, who doesn’t? What a goofy thread
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c0ncEpT
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c0ncEpT 4/17/2020 7:59am
4/17/2020 7:59am
Old thread but I used a Ryobi gas pressure washer all year with a 30 gallon tank sitting on the tailgate of the truck gravity fed. Never had a single issue.
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Falcon
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Falcon 4/17/2020 8:10am
4/17/2020 8:10am
Jbulz wrote:
Install lift kit in your truck = increased supply pressure from the barrel being higher up!

Now I get why all the motobros do it Grinning
I was going to mention this. Or, install one of these:

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Hman144
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Hman144 4/17/2020 8:28am
4/17/2020 8:28am
20 psi from a gravity system? Pressure is 0.433 psi/ft., so that would require that the top of the water be 20/.433 or 46 ft. high. Makes no sense.
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nicko-31
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nicko-31 4/17/2020 8:33am
4/17/2020 8:33am
Mike_Sabol_314 wrote:
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work. It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM...
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work.

It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM Gas Pressure Washer with a Honda motor. The book says minimum 20 psi input water pressure and if you do the math you only get 16-17 psi with a tank in the back of a pickup truck.

https://www.tractorsupply.com/tsc/product/simpson-h326-ms60773-2800-psi…

I’m hoping someone can verify gravity fed water works with this pressure washer.

Thanks!

526 wrote:
Have this exact unit and gravity feed off a barrel and it works perfect.
Or you can just keep the barrel in a pick up truck bed while the washer is on ground level and it helped my pressure washer.
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ns503
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ns503 4/17/2020 8:58am
4/17/2020 8:58am
We have had washers before we fed from a tank no issue.

But not this one. Manual even specs needing pressure. Buried in the trouble shooting section. 30psi. Googling says it's very common. Some do, some don't. But aside from this thread, I could find nothing on the whole internets about modifying (i.e 'remove check valve') so it would.

So ya, if someone could add on that aspect - it would be much appreciated. Otherwise, might have to get a small gas pump for between the tank & washer. Don't really want to go to that hassle. And added expense.
Whymee
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Whymee 4/17/2020 9:13am
4/17/2020 9:13am
I use a 12V on demand pump with a flow rating larger than the pump that it is feeding.
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mx510
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mx510 4/17/2020 10:30am
4/17/2020 10:30am
We have gravity fed for years, it works perfect out the track.
Mike_Sabol_314 4/17/2020 10:39am
4/17/2020 10:39am
mx510 wrote:
We have gravity fed for years, it works perfect out the track.
The only issue is if you look at the manual of the pressure washer there may be a minimum required input pressure. I'm not sure if this is true for all pressure washers, but for the one this thread was started for stated a minimum 20 psi input. Although, someone commented it worked just fine with gravity feed out of a truck bed.

The guy that just posted today asked about a pressure washer that has 30 psi minimum input pressure stated in the manual. I think in the past people have said to just remove the check valve. The check value appears to be the part that needs that pressure to fully open and allow the required amount of water to flow to the pump.

My advice would be to find the serial number of the pump and look up the part schematic for it and find the check value.
ns503
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ns503 4/17/2020 12:34pm
4/17/2020 12:34pm
mx510 wrote:
We have gravity fed for years, it works perfect out the track.
Mike_Sabol_314 wrote:
The only issue is if you look at the manual of the pressure washer there may be a minimum required input pressure. I'm not sure if...
The only issue is if you look at the manual of the pressure washer there may be a minimum required input pressure. I'm not sure if this is true for all pressure washers, but for the one this thread was started for stated a minimum 20 psi input. Although, someone commented it worked just fine with gravity feed out of a truck bed.

The guy that just posted today asked about a pressure washer that has 30 psi minimum input pressure stated in the manual. I think in the past people have said to just remove the check valve. The check value appears to be the part that needs that pressure to fully open and allow the required amount of water to flow to the pump.

My advice would be to find the serial number of the pump and look up the part schematic for it and find the check value.
Had another reply typed out then connection issues. Arrgh.

Anyway. I googled all over the place. I think mine & a lot of others have like 6 check valves inside and they all work together to make the pump do its high pressure thing. Maybe 3 on the inlet side & 3 on the outlet side. And to get mine out I have to basically destroy them to get them out - screw a big screw in then pull out by the screw with vice grips. Which I don't really want to start doing - with a new pump, and not knowing if it will do what I want in the end anyway. Sounded from earlier replies like some have actually done this, but now thinking maybe not. But if so, a bit more detail would be good.

What did you end up doing with yours?

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mxtech1
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mxtech1 4/17/2020 4:42pm
4/17/2020 4:42pm
mx510 wrote:
We have gravity fed for years, it works perfect out the track.
Mike_Sabol_314 wrote:
The only issue is if you look at the manual of the pressure washer there may be a minimum required input pressure. I'm not sure if...
The only issue is if you look at the manual of the pressure washer there may be a minimum required input pressure. I'm not sure if this is true for all pressure washers, but for the one this thread was started for stated a minimum 20 psi input. Although, someone commented it worked just fine with gravity feed out of a truck bed.

The guy that just posted today asked about a pressure washer that has 30 psi minimum input pressure stated in the manual. I think in the past people have said to just remove the check valve. The check value appears to be the part that needs that pressure to fully open and allow the required amount of water to flow to the pump.

My advice would be to find the serial number of the pump and look up the part schematic for it and find the check value.
ns503 wrote:
Had another reply typed out then connection issues. Arrgh. Anyway. I googled all over the place. I think mine & a lot of others have like...
Had another reply typed out then connection issues. Arrgh.

Anyway. I googled all over the place. I think mine & a lot of others have like 6 check valves inside and they all work together to make the pump do its high pressure thing. Maybe 3 on the inlet side & 3 on the outlet side. And to get mine out I have to basically destroy them to get them out - screw a big screw in then pull out by the screw with vice grips. Which I don't really want to start doing - with a new pump, and not knowing if it will do what I want in the end anyway. Sounded from earlier replies like some have actually done this, but now thinking maybe not. But if so, a bit more detail would be good.

What did you end up doing with yours?
I modified mine years ago. It was a Briggs & Stratton motor with integrated high pressure pump. It is correct you have to removed the inlet side check valves. I originally got this information from a small engine repair shop owner who did a lot of these mods for service truck industry. Yes, there is some specialized tooling that can make it easier, but cheaper just to buy a pump.
ns503
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ns503 4/18/2020 8:38am
4/18/2020 8:38am
The more I look the more leery I am. Seems one semi-common cause of low output pressure is dirt in a check valve. So pulling a check valve out would give kind of the same effect - no check valve = one stuck open from dirt. Unless that is only output valves. Also read it (dirty valve) could cause bad pulsing. Maybe that is an open inlet one.

Seems if there was a simple fix I would be able to find more on more people doing it. One thing that is quite common is people buying one to feed off a tank only to find out it won't - so if there was a fairly simple pump fix/mod to overcome that like pulling a check valve, there should be more about it on the internets aside from just this one thread.
mike_v812
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mike_v812 4/18/2020 4:36pm
4/18/2020 4:36pm
I got the same pressure washer with a 55gallon drum which I usually fill half way. Slightly elevated water source ABOVE pressure washer (mine is in the trailer 1’ above the ground MAYBE!). Use the shortest hose possible from the water source to the pressure washer, that is key, mine is roughly 15’ also turn the water on and purge the air from the hose before connecting it to the pressure washer those 3 steps make and break the process. Make sure to take the cap off the drum if it has one.Mine usually builds pressure within 10-20 seconds. This was originally my dads set up and it has worked for 30 years with different pressure washers. In a way it’s almost like siphoning gasoline once you get the flow going it rolls Till empty! There’s nothing like rolling out of the track with clean shit that goes right out of the trailer and into the garage.
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Bruce372
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Bruce372 6/12/2021 9:12pm
6/12/2021 9:12pm
Mike_Sabol_314 wrote:
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work. It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM...
Has any one tried to gravity feed this pressure washer? I’m not sure if it will work.

It’s a Simpson H326 MS60773 2800 PSI 2.3 GPM Gas Pressure Washer with a Honda motor. The book says minimum 20 psi input water pressure and if you do the math you only get 16-17 psi with a tank in the back of a pickup truck.

https://www.tractorsupply.com/tsc/product/simpson-h326-ms60773-2800-psi…

I’m hoping someone can verify gravity fed water works with this pressure washer.

Thanks!

Did any of you guys test gravity feed on this pressure washer?

I picked up a 110v transfer pump from harbor freight as well that I can run from the outlet on my truck. The silverado bed outlet won't power a electric pressure washer
dunndetailedit 6/12/2021 11:41pm
6/12/2021 11:41pm
Throw that away, get you a belt drive Pw a 65 gallon tank, 1inch inlet hose, and a filter between tank and pw then send it and never worry bout it again.
Bruce372
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Bruce372 7/3/2021 9:53pm
7/3/2021 9:53pm
So I bought this simpson 2800 mega shot honda pressure washer. It won't run off gravity feed, so here is the setup I used to get it working from the back of my truck.








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