Pressure Washer Problem

[westhinder]

My pressure washer appears to have given up the ghost. First it developed a sort of stutter: building up pressure and losing it again, as if a pressure valve opened, in rapid succession. After a few minutes trying, it stopped building Pressure, although the motor was still running.
Is there anything I can do to rectify this? I have a strong suspicion that a professional repair will be more expensive than the cost of a new machine.
It is a nearly 20 year old electrical Karomat, a brand that is no longer distributed here.

 

[Sneaky Pete]

Go and spend some money no wonder the company is out of business.

 

[Cymrogwyllt]

Water supply insufficient?

 

[david_bagshaw]

dont supose the water supply is low pressure and it is sucking in air, or failed joint some where, hopefully not caused by frost.

 

[westhinder]

Water supply insufficient?

Water supply is ok

 

[westhinder]

dont supose the water supply is low pressure and it is sucking in air, or failed joint some where, hopefully not caused by frost.

I do not think frost is a factor, as we haven't had a cold winter

 

[Tam Lin]

When mine stopped working I undid it all and cleaned what I could and it worked again when I put it back together. Worth a try!

 

[daveyw]

I'm guessing it has a relief valve and/or recirc valve? Is it stuck open or broken?

 

[westhinder]

I'm guessing it has a relief valve and/or recirc valve? Is it stuck open or broken?

That is my guess too. Any idea what such a valve looks like?

 

[Plevier]

A partially blocked nozzle is a possibility.

 

[Falling Star]

If the design is similar to a Karcher, there will be a valve in proximity to the on/off switch. When the switch is in the "on" position, the valve will actuate the switch to power the pump.

This actuation is dependent on a release of pressure. i.e. when the wand lever is depressed. So, as water comes out of the wand, the pressure drops, the valve actuates which turns on the pump to maintain pressure.

If the valve sticks then you either have a "motor on permanently" situation with no build up of pressure. Or, if it sticks the other way, then you don't get any power to the motor as the switch isn't actuated.

I've made this sound complicated but it's simple if you have a look. Just pull it all apart and spray with WD40 before re-assembly. Usually works.

 

[westhinder]

.

If the design is similar to a Karcher, there will be a valve in proximity to the on/off switch. When the switch is in the "on" position, the valve will actuate the switch to power the pump.

This actuation is dependent on a release of pressure. i.e. when the wand lever is depressed. So, as water comes out of the wand, the pressure drops, the valve actuates which turns on the pump to maintain pressure.

If the valve sticks then you either have a "motor on permanently" situation with no build up of pressure. Or, if it sticks the other way, then you don't get any power to the motor as the switch isn't actuated.

I've made this sound complicated but it's simple if you have a look. Just pull it all apart and spray with WD40 before re-assembly. Usually works.

It is a case of motor permanently on and no pressure building.
I'll give it a try and take it apart as far as I can. Can't do much wrong as it does not work anyway

 

[Falling Star]

I'm not familiar with Karomat, and I don't know if all Karcher models are as described, but I think the principal will be the same.
It does sound like valve trouble.

When the switch assembly is out of the way, the valve may just pull out of the casting. Looks like a nylon plunger and is spring loaded in one direction.

As you say, nothing to lose. Good luck.

 

[solar]

Not trying to steal this thread only to extend it a bit..
My new small Karcher P/W is supposed to suck soap and other cleaning stuff throw a short small hose at the back of the unit that goes into a bucket or a bottle.
It is not working no matter what I do!
Can anyone help on this?
TIA

 

[bikerbill]

Not trying to steal this thread only to extend it a bit..
My new small Karcher P/W is supposed to suck soap and other cleaning stuff throw a short small hose at the back of the unit that goes into a bucket or a bottle.
It is not working no matter what I do!
Can anyone help on this?
TIA

I had the same problem with my Karcher. It won't suck soap through if you have attachments on the lance, take them off then try again using only the handle part of the lance.

 

[Jamesuk]

dont supose the water supply is low pressure and it is sucking in air, or failed joint some where, hopefully not caused by frost.

My first thought, +1

 

[daveyw]

I had the same problem with my Karcher. It won't suck soap through if you have attachments on the lance, take them off then try again using only the handle part of the lance.

I'm guessing this works via a venturi. With the pump operating try blowing up the soap suction tube.if that doesn't clear it try cleaning the venturi.