# Nilfisk packed up - start/stop valve



## ScottR

After less than 3 years of occasional use, my Nilfisk C120 gave up the ghost. I retract any recommendations I ever gave about this being an excellent machine for the money.

For a while it would occasionally splutter into life for a split second every so often when I wasn't pulling the trigger. Pulling the trigger it would work fine, it was just annoying when it was just 'sitting there'. Then it gradually got worse, and it got to the point where it would just 'stutter', constantly trying to prime as thought there was a leak.

It seemed likely there must be a pressure switch, so I pulled it to bits. Sure enough, I found a microswitch attached to a fibre nut thing. 









Turns out this was the Stop/Start valve. Idea is that you switch on your machine, and the start/stop valve turns the pump off once the pressure has built up inside. As soon as you press the lance trigger, the pressure inside the compressor housing drops slightly whilst you have the lance firing, then as soon as you take your finger off the trigger, it stops the pump... which should stop the thing burning out/exploding!

I took the valve out, and could see the remnants of a chewed up O-ring.









Thankfully I had a shedload of Halfords O-rings, so I replaced the O-ring with something a similar size. 









Still wasn't working. I tried various different o-rings, but nothing would work. In the end, I bought a new stop/start valve from eBay.

New valve arrives... guess what... Still ****ed!

The microswitch works, as I can start/stop the pump by sliding a screwdriver in to mimic the start/stop valve piston extending.

What I noticed was that the piston wasn't moving very freely, so I bought some silicone grease and used that on the piston. It did move a little more freely, but still not enough to: a) extend the piston out far enough to press the microswitch in or b) allow the piston to retract smoothly every time when the pressure is released (by pulling the lance trigger).

Has anyone had this issue before? I'm unsure if the plastic 'cup' which sits inside the compressor housing (left of the photo below) is suppose to slide up and down, or just the main piston??









If it is the former, i'm wondering if the metal housing has got 'sticky' from the o-ring constantly rubbing up and down it. If that is the case, any ideas how I could polish up the inside of the housing? And would a coating of silicone grease be sufficient to stop it sticking again?









It is, for want of a better phrase... doing my **** in!!!


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## realist

Mine had the same problem at the same age, commonly known as the pulse of death. Just bought a new one.


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## jetski

You can add me to the club as from last week  mine was 2 and half years old had little use looked almost as new so annoying, I put the pulsating down to a Hozelock waterstop connection I was using but after reading everyone else having a problem maybe not, my motor just completely stopped working couldn't get a peep out of it, really is a pity otherwise they are such a great machine.


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## skodadriver

Like most things these days,built to a price.


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## gordonpuk

I don't have an answer to your problem but I would say Hydraulic valves aren't as straight forward as would seem.

Take a look at http://en.wikipedia.org/wiki/Solenoid_valve

Can't say it'll help but it might put 'new eyes' on it.
I know it refers to a electrical solenoid but that's just the actuation 'power' could be anything.


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## sjstrange

Thread revival I know!!

Scott - Did you ever fix this or did you simply bin it and replace? My nilfisk is doing exactly the same now, and instead of wasting time trying to fix it id like to learn from your efforts!

cheers
Steve


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## euge07

sorry to be negative but I feel 3 years use of a budget pressure washer is pretty decent,

I purchased a comet ks1700 at the weekend for myself and it cost £330 +VAT

It has all brass internal parts and feels a really good quality powerful machine built to last, 

Id invest in a quality machine next time round,


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## ffrs1444

I had a c120 forever braking down went back to nilfisk twice and repaired then bought the cheaper c110 never had a issue in 3 years


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## Puntoboy

Personally I think 3 years from a consumer grade pressure washer is good going. If it had been an E or P series then I'd be a little miffed. My second hand E140 is still going over two years on. 


Sent from my iPhone using Tapatalk


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## 0asis2007

ScottR said:


> After less than 3 years of occasional use, my Nilfisk C120 gave up the ghost. I retract any recommendations I ever gave about this being an excellent machine for the money.
> 
> For a while it would occasionally splutter into life for a split second every so often when I wasn't pulling the trigger. Pulling the trigger it would work fine, it was just annoying when it was just 'sitting there'. Then it gradually got worse, and it got to the point where it would just 'stutter', constantly trying to prime as thought there was a leak.
> 
> It seemed likely there must be a pressure switch, so I pulled it to bits. Sure enough, I found a microswitch attached to a fibre nut thing.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Turns out this was the Stop/Start valve. Idea is that you switch on your machine, and the start/stop valve turns the pump off once the pressure has built up inside. As soon as you press the lance trigger, the pressure inside the compressor housing drops slightly whilst you have the lance firing, then as soon as you take your finger off the trigger, it stops the pump... which should stop the thing burning out/exploding!
> 
> I took the valve out, and could see the remnants of a chewed up O-ring.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Thankfully I had a shedload of Halfords O-rings, so I replaced the O-ring with something a similar size.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Still wasn't working. I tried various different o-rings, but nothing would work. In the end, I bought a new stop/start valve from eBay.
> 
> New valve arrives... guess what... Still ****ed!
> 
> The microswitch works, as I can start/stop the pump by sliding a screwdriver in to mimic the start/stop valve piston extending.
> 
> What I noticed was that the piston wasn't moving very freely, so I bought some silicone grease and used that on the piston. It did move a little more freely, but still not enough to: a) extend the piston out far enough to press the microswitch in or b) allow the piston to retract smoothly every time when the pressure is released (by pulling the lance trigger).
> 
> Has anyone had this issue before? I'm unsure if the plastic 'cup' which sits inside the compressor housing (left of the photo below) is suppose to slide up and down, or just the main piston??
> 
> 
> 
> 
> 
> 
> 
> 
> 
> If it is the former, i'm wondering if the metal housing has got 'sticky' from the o-ring constantly rubbing up and down it. If that is the case, any ideas how I could polish up the inside of the housing? And would a coating of silicone grease be sufficient to stop it sticking again?
> 
> 
> 
> 
> 
> 
> 
> 
> 
> It is, for want of a better phrase... doing my **** in!!!


Bumping to revive pics as I have the same machine with the same issue.....


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## Atkinson91

Today, I cured my E140 from the pulsing plague. Hopefully I can share some insight.

Parts i replaced were:
NILFISK E140.3 CAPACITOR 25UF 128500636 SKU NILFISK_128500636

NILFISK E140.3 MICROSWITCH BOX COMPLETE 128500628 SKU NILFISK_128500628

NILFISK E140.3 START/ STOP VALVE 128500626 SKU NILFISK_128500626

if your looking to do a similar thing but dont have an e140.3 (MUST BE THE .3) id suggest going to find the exploded diagrams for your particular PW and getting the part numbers/SKU's from that


I tried messing around with pump and motor for a week or so at work, replacing the spring, replacing o-rings, smoothing out the plastic, getting it tested by the sparks etc.... everything was fine with those components.

now on to the 'consumable' parts

Now, this is where i found a problem. When I took the microswitch apart, there is a small plastic tab that slides up and down to make contact with the switch when the plunger from the stop/start valve pushes it enough. I thought it was down to the plastic tab running 'dry' and seizing a little.....Anyway, no amount of silicone grease cured that.

When i looked closer at the tab i noticed the stop/start piston had worn a grove slightly bigger than what it wanted to be, I tested this by taking the small plastic tab from a brand new microswitch and putting it into my old microswitch......Pulsing ceased

Maybe it was down to just this plastic piece inside the microswitch being worn slightly and spring tension being lost over the course of 2-3 years worth of pulsing, im not certain....but replacing those 3 things has brought my nilfisk back to life. Hopfully it will do the same to yours!


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## BruceVolvo

The stop/start valve went on my E150 2-10 a month ago and it was virtually new, got it in January this year, had it fixed under warranty so not an issue but as a £290 machine I don't consider it to be a budget throw away item and if its likely to go again in 2-3 years time I'll be pretty peed off. The chap at the service shop said he had seen a lot with this issue right across the range and Nilfisk are aware of the issue. Makes me wish I had waited a couple of months and for an extra £200 I could have had a Kranzle.


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## ffrs1444

I went through 2 c120s my replacement c110 lasted 4 years now on the Nilfisk Titan which has a 3 year warranty


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## mangove21

I've just done this, replaced all 3 parts as suggested and now works like a dream! 

Sent from my ONEPLUS A5000 using Tapatalk


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## Caledoniandream

Puntoboy said:


> Personally I think 3 years from a consumer grade pressure washer is good going. If it had been an E or P series then I'd be a little miffed. My second hand E140 is still going over two years on.
> 
> Sent from my iPhone using Tapatalk


My Karcher is over 10 years old (K3 something) used weekly on 2-3 cars, never missed a beat
Have a Nilfisk C120 ( bought it to see where all the fuss was about) been used no more than 30 times in 4 years and has exactly the same issue.

We have a Professional Karcher at work (diesel heated hot water) and is now over 20 years, with yearly oil change and a couple of Belts and the odd sparkplug over the years, still going strong


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## Tazgalsinh

Atkinson91 said:


> Today, I cured my E140 from the pulsing plague. Hopefully I can share some insight.
> 
> Parts i replaced were:
> NILFISK E140.3 CAPACITOR 25UF 128500636 SKU NILFISK_128500636
> 
> NILFISK E140.3 MICROSWITCH BOX COMPLETE 128500628 SKU NILFISK_128500628
> 
> NILFISK E140.3 START/ STOP VALVE 128500626 SKU NILFISK_128500626
> 
> if your looking to do a similar thing but dont have an e140.3 (MUST BE THE .3) id suggest going to find the exploded diagrams for your particular PW and getting the part numbers/SKU's from that
> 
> I tried messing around with pump and motor for a week or so at work, replacing the spring, replacing o-rings, smoothing out the plastic, getting it tested by the sparks etc.... everything was fine with those components.
> 
> now on to the 'consumable' parts
> 
> Now, this is where i found a problem. When I took the microswitch apart, there is a small plastic tab that slides up and down to make contact with the switch when the plunger from the stop/start valve pushes it enough. I thought it was down to the plastic tab running 'dry' and seizing a little.....Anyway, no amount of silicone grease cured that.
> 
> When i looked closer at the tab i noticed the stop/start piston had worn a grove slightly bigger than what it wanted to be, I tested this by taking the small plastic tab from a brand new microswitch and putting it into my old microswitch......Pulsing ceased
> 
> Maybe it was down to just this plastic piece inside the microswitch being worn slightly and spring tension being lost over the course of 2-3 years worth of pulsing, im not certain....but replacing those 3 things has brought my nilfisk back to life. Hopfully it will do the same to yours!


Hi.my e140.3 has the pulsing now. Where did you buy your parts from and did you find any dagrams to follow? Thanks


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