# Nilfisk C120 - Pumping/ Pulsing on standby



## Slammedorion (Apr 13, 2014)

I've looked at many C120 pulsing threads... but can't find a definite fix for pulsing on standby 
I've checked inlet and outlet seals - all ok
Checked inlet filter ( was clean )
Presume I need to pull the machine apart... although there seems to be no visible leaks
I have read somewhere about a faulty pressure switch could be the culprit
Anyone help?


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## OvEr_KiLL (Mar 2, 2015)

o rings if you havnt already.?


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## justinio (Jun 24, 2013)

There will be a small leak somewhere. Just a matter of chasing it down. 

Sent from my Nexus 9 using Tapatalk


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## Slammedorion (Apr 13, 2014)

OvEr_KiLL said:


> o rings if you havnt already.?


Inside the machine?


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## OvEr_KiLL (Mar 2, 2015)

Slammedorion said:


> Inside the machine?


no, theres one of the end of the intlet for the hose pipe connector and also one of the bit that clips in the gun


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## neilmcl (Mar 26, 2010)

I had the same with mine a couple of months ago, got some o-rings and changed the one on the hose end that connects to the gun as I noticed a few drips at that end. Completely fixed the problem.


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## Slammedorion (Apr 13, 2014)

It's not leaking though?
Works fine when I press the trigger...
Just pulses away on standby?


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## neilmcl (Mar 26, 2010)

Slammedorion said:


> *It's not leaking though?*
> Works fine when I press the trigger...
> Just pulses away on standby?


No that you know of. Mine worked perfectly fine too but did exactly the same as yours and pulsed on standby. It started of once in a while then eventually once every 10 secs or so. Seriously, get a replacement o-ring kit and start eliminating potential areas starting with your hose.


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## simonvespa (Apr 18, 2012)

Have a look at this thread and contact Steve at North West Pressure Washers. If you have checked for leaks it could well be the Start / Stop valve.

http://www.detailingworld.co.uk/forum/showthread.php?t=386104

Cheers

Simon


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## Slammedorion (Apr 13, 2014)

neilmcl said:


> No that you know of. Mine worked perfectly fine too but did exactly the same as yours and pulsed on standby. It started of once in a while then eventually once every 10 secs or so. Seriously, get a replacement o-ring kit and start eliminating potential areas starting with your hose.


Mines pulsing every 1-2 seconds... :lol:


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## neilmcl (Mar 26, 2010)

I bought the following http://www.ebay.co.uk/itm/Nilfisk-P...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649 and I've seen them cheaper. Literally to 5 mins to sort the issue out.


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## ffrs1444 (Jun 7, 2008)

Get rid and get a c110 I had loads of problems with my old C120 never a issue with the c110


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## OvEr_KiLL (Mar 2, 2015)

ffrs1444 said:


> Get rid and get a c110 I had loads of problems with my old C120 never a issue with the c110


get rid of it when he probably only needs a o ring somewhere that is cheaper than buying a c110..great!
its pulsing because its trying to build up pressure and cant. change the o rings


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## neilmcl (Mar 26, 2010)

ffrs1444 said:


> Get rid and get a c110 I had loads of problems with my old C120 never a issue with the c110


Bit OTT for what could probably be a very simple and cheap fix don't you think.


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## Slammedorion (Apr 13, 2014)

neilmcl said:


> I bought the following http://www.ebay.co.uk/itm/Nilfisk-P...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649 and I've seen them cheaper. Literally to 5 mins to sort the issue out.


I've ordered them cheers :thumb:


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## Leebo310 (Sep 30, 2013)

Presume it's outside of the 2 year warranty?


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## SuperchargedLlama (Apr 25, 2008)

I remember seeing in another thread that someone worked out that it was the stop flow connector on the hosepipe that was causing it - if the o-rings don't solve it do check that out as well (of course, if you don't have those connectors anywhere in the setup then it won't be that!)


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## Slammedorion (Apr 13, 2014)

I've replaced the seals and it's made no difference...
Will need to open it up and take a look once my long reach torx screw drivers arrive
Any other ideas?
Anything I can take apart and check its clean, or and other seals inside that can be changed, or is it likely to be the pressure switch?


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## scooobydont (Feb 25, 2017)

How old is it? I have just had the same issue with my c110. It is just over a year old and has a 3 year warranty (I think). I emailed Nilfisk and after exchanging a few details they are sending me a new one under warranty.


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## scooobydont (Feb 25, 2017)

That my warranty replacement arrived . They dont even want the old one back.

Great service from Nilfisk.


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## Argee45 (Aug 24, 2017)

If it's not leaking, it's probably the Start/Stop valve (sometimes called the Unloader Valve), which stops the pump when the trigger is released.

Ray


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