[Russ Chadd]

Hi

For the first time i wound the pressure right up on my 2010 model prowler 13 hp and the maximum the gauge would read was 1500 psi (in bypass) and the maximum output pressure was about 1300 psi.
looking at the jet whilst in operation it looks to be pulsing and the pressure gauge is not reading a steady pressure.

Just wondered if this sounds like a dirty or worn valve in the pump?
I de scaled the system today but this didnt make any difference
Any ideas guys?

Russ

[Kinver_Clean]

I think this is the natural pulsing of the pump. Without an accumulator in the line this will happen anyway.

[PaulKing]

running from a tank ?
try it with a hosepipe attached

also ( in bypass) what does that mean you have the bypass open if so there's the problem

[Mike Halliday]

Slipping belt perhaps.

You could take out the high pressure valves and give them the suck test to see if they are ok

[Russ Chadd]

Bypass meaning when the trigger is not depressed water re circulates in the pump and a pressure reading of 1500 is shown.
Has anyone else turned the pressure to max on their prowler?
Have checked the belt and its not slipping and is at a good tension.

Are the valves easy to remove on this pump for inspection?

Cheers

Russ

[davep]

Why do you want so much pressure?

[Russ Chadd]

The unit should be kicking out 2000psi and its 500psi short, its ok Dave i dont clean carpets at 2000 psi, its a case of finding out why the pump is short of max pressure.
the machine is being worked off mains water not a tank

 

[jim mca]

whats the flow rate if its over 8lpm then it might be the water cant keep up and you need a tank to keep up

[Mike Halliday]

2000psi is probably the pump max psi but lots of things could be effecting this...... the engine could be running less than max rpm or if it is pully driven it might be under driven, is the pump pully bigger than the pully on the engine?

[richie]

ok, any machine no matter what it is will often have a gauge that goes up to 2000psi this does not mean it can go up to that pressure.  Often the pumps are limited, yes they might say 2000psi on the pump but may not be able to on that machine.  Also, very often the heat exchangers are not able to cope with those kind of pressures and damage can happen (burst).

[Russ Chadd]

Guys....
Anyone have the same machine and if so have you managed to get 2000 psi from it?
Richie... the pump is rated at 2000 psi... in all the prowlers marketing it clearly states that the machine's maximum output is 2000 psi.
The purpose of this excise is to make sure the pump is working correctly, i have had past experience with pressure washers developing similar performance issues and 9/10 times its been a stuck valve.

If no one else's prowler has reached this pressure then i guess its all normal

[richie]

Yes the pump may well be rated at 2000psi and that pump in certain situations can / will give that pressure.  Often the makers of machines will put specs up for you to see that make the machine look more attractive but often they actually make it so maximum performance is lower than what the specs of individual components are capable of.   If you are wanting to check the pump is giving correct flow you will need to connect a open pipe at the pumps outlet, if the pump says it will give 20 lpm then get a 20 lire container and see how much it pumps in to it in one minute.

[PaulKing]

it should go to 2000, all of mine did, its either

leaking dema valve with grit in it
leaking bypass valve ( which is why i wondered about in bypass in your post)
Worn non return valves in the brass pump head which are a pice of piddle to change just a 1inch socket and there are there.
or worn piston seals in the head which needs you to take off the five or six allen headed bolts and change them along with the rings.

My money is on the worn seals, they are a service item and meant to be changed, also if machine has ever had frost they will be shredded.

[Russ Chadd]

At last!

Thanks Paul you have been very helpful... I tried to remove one of the 24mm valve hex bolts located on the pump today but non of them wanted to budge.
So you would start with taking the head off and checking the piston seals? is there a way of testing them or is it just looking to see if any of them have perished?

Does your pressure gauge give a steady reading or does the needle wobble (at the lower revs)
I have had a similar problem with Karcher pressure washers which have grit or scale lodge in one of the valves and makes it runs like a car engine on 3 cylinders

Thanks again

[PaulKing]

you just sent me a video with the bypass open that doesn't recirculat it in the pump it dumps it out the discharge,  so you'll never get 2000 psi that rating is the pump pressure against against a closed valve, all TM's are the same the set pressure is not the same reading when you open a valve or trigger on the wand it drops a bit, as for discharge from the hose that again is because the bypass valves is open thats were it goes to. it should be shut on cleaning carpets the maker only says to open a little  when cleaning upholstery, and theres a bypass on the carpet wand for when you in house and not working. 



looks like its working ok, the exhaust moisture happens on start up if its cold its condensation, cars do it as well.

[Russ Chadd]

Paul, excuse my ignorance... when you say the bypass is open what do you mean? i never had the bypass open on the front of the machine and the wand obviously wasn't attached.
So the pump was re circulating hence there was a reading on the gauge.
The only valve which was open slightly was the valve which directs cool water to the pump to cool it and i understand that this water ends up being forced out of the blower exhaust... but at low volumes.