Low PSI

Tim Smith

New Member
I have a 11hp Honda 3000psi 4.0gpm



I bought the unit used and replaced the broken guage. The psi gage reads no more than 2000psi at full throttle. Once again, new at this-any advice on how to get the unit to reach 3000psi.

The prev owner rebuilt the pump last year. The engine runs like a champ

Everyonce in awhile the unit will pulsate. I shut engine down and restart and it stops.

Thanks
 
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ron

New Member
ron p

MARK is the man to talk too or the WIZ.
I am going to guess the first thing they are going to tell you is you have a air leak- its drawing air somewhere tighten all your hose clamps first. then repost if it wont help
thats gives you a starting spot anyway.
if you have a pic of the unit to post it will save you a ton of time.
The next question they will ask is what kind of unloader you have?
What brand pump?
what size tip?
is the tip new?
what are the #s on the tip?
 

Tim Smith

New Member
Ron

You are right.

I talk to Mark and he wants to know

spike pressure
size nozzle
model # of pump

I am going to get that info for him-I let you know what happens.
 

oguard

New Member
At an approximate cost of $30 you cannot expect precise pressure readings from you gauge. At best they are accurate to +/- 10% or more. As a matter of fact it is my opinion that a pressure gauge is of limited value due to this fact. You will know fairly soon when your machine is working up to snuff.

However, knowing the pump model, horsepower, nozzle size etcetera will help to determine if you bought a pig in a poke or need a bit of service assistance.

Hope this helps?
 
H

Hotwaterwizard

Guest
Put a #4 tip on the machine and test it. When you let off the trigger the psi should not excede 3500psi
If higher adjust the unloader so the spike is a little lower than 3500 psi.




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Mark

Moderator / Sponsor
Tim,

I thought maybe you found the problem as I had not heard
from you since Friday? Let me know if you need my assistance.

P.S. looks like some others have given some things to check also.

This is the board to go to when you need help!
 

Tim Smith

New Member
Mark

We have had a cold front come through. Its been around 35 degrees during the day and around 18 degrees at night. The weather has been crazy.

Waiting on it to warm up before operating and testing the unit.

I will let you know.


I am amazed at all the knowledge on this board.



Thanks
Tim
 

Tim Smith

New Member
I had a 5.0 tip Pressure read 2400 psi with gun closed, when I open gun it spike to 1500 psi.

Put a 4.0 tip on wand Pressure read 2400 osu with gun closed, when I open the gun it spike to to 2100 psi.

Still low psi - I did find a leak at back of the pump where the water hose and wand hose connect. There is a casing/bracket that connects to pump (This casing houses the connections to the hoses) - it leaks water pretty bad. Is that just a matter of replacing a seal. I can not find a part number or serial number on the pump. This casing that I mention has a list of numbers but not the pump.

How do you adjust the unloader?
Do I need to adjust it?

Any advice would be appreciated.
 
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oguard

New Member
Still need to know what horsepower motor/ engine you are using and the make/ model # of the pump.

At 1500 PSI with a #5 tip it works out to be 3.1 GPM, a #4 tip works out to be 2.9 GPM.

Therefore I guess you are using a 3-4 HP electric motor or a 5-6.5 HP gas engine. If this is the case then you are getting all expected performance. But we need the information above before we can determine if it is nothing more than your gauge being out-of-whack.
 

Mark

Moderator / Sponsor
Tim,

I asume this is a direct drive pump, if it is blue it is most
likely a Cat pump, it could also be an AR pump, a Comet pump. General,
or on and on. If you can send me a digital picture I will try to identify it.
 

ron

New Member
ron p

TIM, i told you so. Mark could have told you what were the main things about your unit that go wrong just by looking at it.
they never listen. lol ["ton of time"] yours and his
 

Tim Smith

New Member
Ron

Your just a smart man! You must be very wealthy with all of your knowledge or are you? lol

I listen with my eyes not my mouth or ears. Think about it. lol
 
H

Hotwaterwizard

Guest
The #4 tip helped didn't it?
Now you have to adjust the unloader at full throttle 3600 rpm!
Here is how it is done.
See the big spring? There should be a screw or a knob on it. Turn it clock wise then pull the trigger and read the guage. Turn again untill it reads 3000 psi with trhe gun pulled. Then let off of the trigger. It will spike at this point to about 3400 psi or higher. If higher turn it back down untill it reads about 3200 to 3400. When you let off it should unload within two seconds. If noe turn it down untill it does. If you still can't get 3000 psi your unloader or packings or check valves could be weak and should be replaced.
 

Bill B

New Member
Tim, if you perform the test that the Wiz suggests and the pressure is low, then you may want to test the pump (to determine if the pump or the unloader is the problem). You must be very careful, or you can blow up the pump!

Pull the unloader, connect the gun with a good nozzle tip. Tie the gun open to insure that it is NEVER closed, esp. on starting. Turn the machine on and check the pressure. If it is ok, the unloader is the problem. If low the pump is the problem (guess both could be the problem). If you have an open gun, use that.

Good luck. I went through this a week ago; lucky it was my unloader.
 

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