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How does a pressure washer capacitor work?
The capacitor assists in the initial boost of power required for the motor to start and run smoothly. When the pressure washer is turned on, the capacitor releases the stored energy, helping to create the necessary electrical current to drive the motor.
What damages the capacitor?
The capacitor becomes worn out with continuous use and results in reduced capacitance or even failure. Voltage spikes, power surges, or electrical faults can also damage the capacitor.
Exposure to excessive heat, moisture, or contaminants can lead to deterioration or corrosion of the internal components, affecting the capacitor's performance.
Is it a genuine spare part?
This capacitor by Karcher is a genuine pressure washer replacement part.Your pressure washer can work good-as-new in cleaning surfaces.
Manufacturers Part Number:
- 6.661-158.0
Alternative Part Numbers:
- 6.661-298.0
- 66611580
- 66612980
EAN Number:
- 4039784529199
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Safety note:
Warning: Always unplug any appliance from the electricity supply before carrying out any work or testing on it.
Latest Product Review(s)
4 Customer Review(s)
Restored Life
My pressure washer dates from around 2003. It is a top-of-the-range domestic model ( Load=2.8kW, 450 L/hour , Max 150 bar ). I had cleaned half of a large decking area so in constant use for ~ 45minutes. After a tea-break the motor would not start and would only make a loud buzzing noise. I immediately stopped using it. The motor start capacitor was found to have leaked extensively and, once replaced with this component, the motor started normally. I can't comment on the quality - It's a capacitor and it appears to work.
By Grahame Blair - Glasgow
16th Dec 2022
Original Quality Replacement Parts
My Karcher K6.85M Pressure Washer suddenly failed to pressurise whilst in use although it remained electrically connected and water continued to flow (though not under pressure). When switched off/on, the motor did not make its usual hum leading me to ultimately diagnose a faulty capacitor. Unfortunately the exploded diagram was unable to clarify the replacement part, offering two choices. Following a little research I opted for the 40MF Capacitor which I ordered from Ransoms Spares. On disassembly I discovered that the failed component was in fact the 25MF version though as my research had indicated that the 40MF version was a good exchange it was fitted into the electrical switch box without issue and more importantly the Pressure Washer returned to life with the replacement fitted. I am advised that the larger value component is an entirely compatible replacement and so far I have not had any operational issues.
By N Lunam - Wirral
13th Jan 2018
Saved me over £500!!!
My Karcher K7.85 stopped working halfway through cleaning the deck and the choice was to take it apart to investigate the cause or put my hand in my pocket and spend over £500 for a direct replacement. The good news was that when I came across the capacitor it showed classic signs of failure (misshapen and distorted). I searched online and found a genuine Karcher replacement part at Ransom Spares. Ransom despatched it very quickly and it arrived safe and sound in no time at all. Once replaced the Karcher operated as new.
By Neil Armstrong - Hemel Hempstead
11th Apr 2017
Great value product
Bought this item from RANSOM SPARES due to the cost. It was by far the cheapest I could find on the internet for the identical item
By Mr Eugene Maher - Driffield
28th Mar 2014
Questions And Answers
1 Answer(s)
What are the dimensions of this part please, length and diameter ?
Hi Joseph, this capacitor is 44.5mm in diameter and 74.6mm long.
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