I have a K2 Karcher pressure washer. The moment I switch it on it seems to give momentarily the correct pressure and then it gives a low pressure. Almost as if it's trying to do the right thing but can't quite make it. Does anyone know what could be wrong and can I repair it?
Is the output nozzle set at the right position - one's for low pressure output and will also suck in detergent through the wee tube, and t'other is for high pressure jet wash. Is it getting enough water supply - straight hose, no kinks, tap full on and working as it should, etc.?
There is plenty of water going in and no kinks. Will check the position of he output nozzle and get back if that's not the problem. Thanks in the meantime.
Is there a filter on the main feed in to protect the pump, there is on mine though it's not a Karcher.
I had a similar issue with a kew pressure washer, worked fine until me hosepipe needed a new connector and I fitted one o' those hozelock aqua stop connectors, the type that has an internal valve to stop the water flow when an accessory (eg a pressure washer) is disconnected. I still dunno why, but it created exactly the same issues as a kinked hose... repeated brief bursts of the correct pressure then sudden pressure loss. Probably not relevant, but thought it worth a mention.
Are you using the correct water in the thing. It could have too much chlorine in it, or too much fluoride. Maybe the tap is brass? Is the loop taughtness factor in the line compromised?
Gulp - once you've checked all of UP's suggestions, Retire Ray's one is worth a looksee. I've had that same issue with these 'shut-off' couplings. They are certainly handy, stopping the water flow when you disconnect an attachment, but - I agree - they can seriously restrict the water flow if the spigot part of the male fitting doesn't go in far enough to fully open the valve. And possibly even if it does. Even tho' some of these fittings have become standardised, you will still get some variations betweens makes, and if the Karcher's thingy ain't long enough, that could well be the problem.
Apparently you're not supposed to use those "shut off" couplings on the washer as it needs 3m of hose to use as some sort of expansion vessel when switching on and off. I only know this cause I used 1 and karcher told me that's what screwed it.
I agree, the auto shutoff ones kill the flow. Had issues on some food prep kit that used them for their supply.