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We are unable to confirm if this part will fit with model number ""Description
What does the pump head do for the pressure washer?
The pump draws water from a water source, typically through a hose, and pressurises it before sending it to the nozzle. Its main function is to increase the water pressure, allowing for effective cleaning of surfaces.
It accomplishes this by using pistons or impellers that create a pulsating or continuous flow of water, depending on the pump type.
What causes the pump head to be faulty?
The continuous operation and exposure to high pressures and water flow can lead to the deterioration of pump seals, valves, or pistons. These components may develop leaks or lose their ability to maintain the required pressure.
Another factor is inadequate maintenance, such as failing to properly winterize the pressure washer, allowing water to freeze inside the pump and cause damage.
Running the pressure washer without an adequate water supply or using water that contains abrasive particles or contaminants can also contribute to pump head failure.
Is it a genuine spare part?
This cylinder pump head by Karcher is a genuine pressure washer replacement part. Your pressure washer can work good-as-new in cleaning surfaces.
Manufacturers Part Number:
- 4.551-159.3
Alternative Part Numbers:
- 45511593
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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)
Read All Reviews
12 Customer Review(s)
Jet wash now working again
Exact replacement for the part I needed to fix a leaking jet washer. Fairly straightforward to fit and saved me the cost of a complete new washer. Fast delivery too.
By Michael Dent - Northampton
11th Jul 2023
Excellent product and service
My Karcher K3 was leaking badly and had significant loss of power. Dismantling showed a blown gasket. Found an exact replacement for whole head unit here, and impressed to find supplied with all connecting O rings and pre-greased. Facility to check compatibility against exact product no added confidence. Ransoms seem to be an excellent company for those of us keen to fix rather than throw away! Don't forget to add lubricant to your order if you make the schoolboy error of opening piston case horizontally and spilling existing piston case lubricant!
By Philip J Bain - Bury St Edmunds
3rd May 2023
Karcher back to life
I had low pressure on my Karcher washer and leak. This unit brought it back to new. It is the part that generates the pressure so will be worn over time. I'd say my pressure washer is about 5 years old, but should do another 5 years now. Easy to fit, and genuine part. Great service fro, ransomespares. Thanks
By Richard Hale - Hampshire
23rd Apr 2023
In stock and fast delivery. Thank you.
Good description on website. In stock and fast delivery. Thank you.
By Bob Woods - Bournemouth
19th Apr 2023
Great value repair
great job thanks turns out i need to replace the high pressure outlet pipe dont leave yer washer out in the ice!
By MARK STANLEY - Bottisham
23rd Feb 2023
Great value repair
The repair is fairly simple for enthusiastic diy and saved cost of new and replacement pressure washer. actually i am back for a second one having left my unit outside in the frost. it leaks water. this will fix your water leak.
By Mark Stanley - Bottisham
7th Feb 2023
Good advice on the right part
I contacted Ransomes to check the right part for my Karcher pressure washer. They were very helpful and quickly confirmed the replacement cylinder head. It arrived in reasonable time and is now fitted, and has fixed the leak. It was reasonably easy to fit - take off all the bodywork and then undo the 4 bolts holding on the cylinder head and its metal retaining strap. NB. Do this last step with the assembly vertical, motor down, as the "gear box" contains oil and lifting the cylinder head off vertically upwards keeps the oil in place.
By Simon Hobson - Warwick
1st Nov 2022
Great
Item perfect fit first class service top class Rey easy to find parts on web page
By Douglas Nichols - Clacton on sea
28th Sep 2021
How long will it last
This plastic cylinder head was purchased to replace an original Karcher one that failed. I'm not a heavy user of pressure washers but it makes you think how long these parts last. At least Karcher make their products easy to dismantle. Thankfully Ransoms are on hand with stock. They delivered it within the week and the website is easy to navigate. Even the exploded diagrams make it easy to reassemble when you wonder where a certain part goes.
By Martin Griffin - HAYWARDS HEATH
18th Sep 2021
Saved me a whole lot of money!
I have a Karcher K2 FC which has leaked for as long as I can remember. This is no surprise. However, I've recently started using the pressure washer a lot more and so I decided to resolve the issue. I disassembled and diagnosed the problem as a damaged cylinder head (one of the cylinder walls was severely scored and there were loose plastic shavings). For an OEM job it transpired that I'd have to visit a service centre and, I assumed, pay a good amount to fix what was a pretty cheap machine. Not happening. Then in stepped ransomspares! On the off-chance I checked for 3rd party supply of parts and found myself here. £20-odd later I had a new part with all seals included and no more leaks - get in!
By Gideon Ring - Bicester
13th Aug 2021
Questions And Answers
1 Answer(s)
What is the difference between the parts RS512102 and RS823884?
They look quite different, but the description is the same...
Hi Luke, please submit a part enquiry including the TYP number beginning 1. from the bottom of the pressure washer so we can confirm the correct cylinder head for your model.
1 Answer(s)
Does it include the groved seal with this cylinder head
Hi Chhotu, please submit a part enquiry including the TYP number beginning 1. from the the rating plate on the bottom of the pressure washer so we can check this for you.
1 Answer(s)
is the cylinder head type you supply no k2 basic 1.673-150 the same as k2basic1.673-158.0
Hi Colin, this cylinder head is for 1.673-158.0. The one for 1.673-150.0 is RS512102.
1 Answer(s)
Hello, i have a K2 premium 1.673-304.0 but the parts seems no be identical I have ref5.061-035
Hi Alain, the cylinder head listed for your model is RS512102.
1 Answer(s)
Hi I have a k4 full control, will this part fit it.
Hi Dave, please submit a part enquiry, including the TYP number, beginning 1. from the rating plate on the bottom of the pressure washer so we can check this for you.
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