So, the reliability issues surrounding the Karcher K4 are pretty well documented - after a while they will wet the bed. I've counted myself lucky that mine has lasted 2.5 years before losing bladder control (others on here get through one every season - a certain @jassyo06 is probably on his 5th or 6th now - feel your pain pal, ****** annoying).
Inevitably, it was 3 months outside it's 2 year warranty, so after swearing lots, kicking it and lamenting that I might actually be tempted to throw 500 sheets at a Kranzle, I've spent an hour this evening stripping the wet-knickered b1tch down to see if I can't diagnose the problem, and fix it. Here's how I got on...
Actually pretty easy to free the guts of the thing from it's plastic housing - just a few (x8) torx screws on the back of the unit, plus a couple of plastic plugs on the base that needed teasing out with a flat head screwdriver, then you're inside. Couple of metal clips to release to get the 'engine' out, but child's play really.
Started off by fully pulling apart the plastic water pump to check for cracks - this is a common fault, especially if you don't drain the pump after each use, and very especially in winter, if the water you haven't drained from the pump pump freezes and expands, and cracks the plastic housing. Why are they made of plastic ***? Such a stupid material for such an integral part. Anyways, that proved fruitless - no fault there, so reassembled.
Problem turned out to be a hairline crack in the plastic elbow on the rear of the unit that connects the exterior hose to the guts of the machine - this also seems to be a common fault - so much so that Karcher sell a metal replacement elbow. (uh, just fit that one as standard). £15 part, ordered, and confident this will fix the fault. Will update once I've fitted it. With hindsight I should have checked for this first before stripping down the water pump.
I was initially intending to smash the damn thing with a hammer and take it down the tip, but having taken the K4 apart, I'm actually quite impressed with how easy it is to take apart, diagnose the fault and fix it yourself. It might end up being like Trigger's broom after a few more years, but you can buy a tonne of replacement spares for it and it is very easy to work on. Still fancy a Kranzle though.
Guts of the machine removed:
Metal water pump housing removed to check the pump for cracks - there weren't any:
Problem turned out to be the plastic elbow going into the machine here:
Here it is stripped out - hairline crack in the join right down the middle - caused complete loss of pressure and a fine spray p1ssing out of the rear of the machine:
Replacement part ordered - metal elbow to replace the cheap plastic one (£15):
This should fix the incontinent old girl! Will confirm once I've finished the fix. Posting in the hope that it helps someone, even if just one person. TBC...
Inevitably, it was 3 months outside it's 2 year warranty, so after swearing lots, kicking it and lamenting that I might actually be tempted to throw 500 sheets at a Kranzle, I've spent an hour this evening stripping the wet-knickered b1tch down to see if I can't diagnose the problem, and fix it. Here's how I got on...
Actually pretty easy to free the guts of the thing from it's plastic housing - just a few (x8) torx screws on the back of the unit, plus a couple of plastic plugs on the base that needed teasing out with a flat head screwdriver, then you're inside. Couple of metal clips to release to get the 'engine' out, but child's play really.
Started off by fully pulling apart the plastic water pump to check for cracks - this is a common fault, especially if you don't drain the pump after each use, and very especially in winter, if the water you haven't drained from the pump pump freezes and expands, and cracks the plastic housing. Why are they made of plastic ***? Such a stupid material for such an integral part. Anyways, that proved fruitless - no fault there, so reassembled.
Problem turned out to be a hairline crack in the plastic elbow on the rear of the unit that connects the exterior hose to the guts of the machine - this also seems to be a common fault - so much so that Karcher sell a metal replacement elbow. (uh, just fit that one as standard). £15 part, ordered, and confident this will fix the fault. Will update once I've fitted it. With hindsight I should have checked for this first before stripping down the water pump.
I was initially intending to smash the damn thing with a hammer and take it down the tip, but having taken the K4 apart, I'm actually quite impressed with how easy it is to take apart, diagnose the fault and fix it yourself. It might end up being like Trigger's broom after a few more years, but you can buy a tonne of replacement spares for it and it is very easy to work on. Still fancy a Kranzle though.
Guts of the machine removed:
Metal water pump housing removed to check the pump for cracks - there weren't any:
Problem turned out to be the plastic elbow going into the machine here:
Here it is stripped out - hairline crack in the join right down the middle - caused complete loss of pressure and a fine spray p1ssing out of the rear of the machine:
Replacement part ordered - metal elbow to replace the cheap plastic one (£15):
This should fix the incontinent old girl! Will confirm once I've finished the fix. Posting in the hope that it helps someone, even if just one person. TBC...
. Was chuckling at the incontinent old girl and wet knickers etc, I experienced that (with a Karcher) before too 
