Product Overview
This control piston is an upgraded replacement part designed for specific Kärcher pressure washer models. It plays a crucial role in regulating the internal water circuits and reducing outlet pressure, acting as an additional protection against overpressure within the system.
It is a direct replacement for the original Kärcher valve with part number 4.553.268.0.
Video: Krajview of the Control Piston and its components.
Specifikacije
| Atribut | Vrijednost |
|---|---|
| Tip | Kontrolni klip |
| Materijal | Brass + 304 Stainless Steel |
| Replacement OEM Part Number | 4.553.268.0 |
| Kompatibilni modeli | Kärcher K 7.20MX, K 720MX, K 7.21MX |
| Težina artikla | 0.12 kg |
| Dimenzije artikla (D x Š x V) | 7 cm x 3 cm x 3 cm |
| Vrsta stavke | Covers & Ornamental Mouldings (Functional Part) |
| Porijeklo | kontinentalna Kina |
Instalacija i podešavanje
This control piston is a critical internal component of your pressure washer's control valve. Installation typically involves disassembling part of the pressure washer pump assembly. Due to the complexity and precision required, professional installation is highly recommended.
If you choose to perform the installation yourself, ensure you have the necessary tools and technical expertise. Always refer to your specific Kärcher pressure washer's service manual for detailed disassembly and reassembly instructions.
General Installation Steps (Consult Kärcher Service Manual for specifics):
- Sigurnost na prvom mjestu: Disconnect the pressure washer from the power supply and water source. Release any residual pressure in the system.
- Pristup pumpi: Carefully disassemble the pressure washer casing and pump head to gain access to the control valve assembly.
- Remove Old Piston: Locate the existing control piston (OEM 4.553.268.0) and carefully remove it, noting the orientation and any associated springs or seals.
- Install New Piston: Insert the new control piston, ensuring all seals (O-rings) are correctly seated and lubricated if necessary. The piston consists of a brass body and a stainless steel spring assembly.
- ponovo sastaviti: Reassemble the pump head and pressure washer casing, ensuring all connections are secure and no parts are left loose.
- Test: Reconnect the water supply and power. Slowly turn on the water and then the pressure washer, checking for leaks and proper operation.

Image: Disassembled view of the control piston, showing the brass main body and the separate spring-loaded stainless steel component.

Image: The control piston shown alongside a Kärcher pressure washer, indicating its application.
Operativni principi
Once correctly installed, the control piston functions automatically within the pressure washer's hydraulic system. Its primary role is to manage pressure fluctuations and prevent excessive pressure buildup. When the pressure exceeds a safe threshold, the piston mechanism activates to open internal water circuits, thereby reducing the outlet pressure and protecting the pump and other components from damage.
Proper operation is indicated by consistent water pressure and smooth functioning of the pressure washer.
Održavanje
As an internal component, the control piston generally requires minimal routine maintenance. However, regular inspection of your pressure washer's overall performance can help identify potential issues early.
- Redovne provjere sistema: Periodically check your pressure washer for consistent pressure output and any unusual noises or leaks.
- Kvalitet vode: Using clean, filtered water can help prevent mineral deposits and debris from affecting the piston's operation.
- Skladištenje: When storing the pressure washer, especially in freezing temperatures, ensure the system is properly drained to prevent ice formation which can damage internal components like the control piston.
Rješavanje problema
Malfunctions of the control piston can lead to several operational problems with your pressure washer. If you experience any of the following symptoms, the control piston may need inspection or replacement:
- Reduced Operating Pressure: The pressure washer delivers noticeably less pressure than usual.
- Intermitentni rad: The pressure washer's pump cycles on and off erratically when the spray gun is engaged.
- Complete Lack of Pressure: The pump runs, but there is no water pressure at the outlet.
- Curenje vode: Leaks from the pump head area could indicate a faulty piston seal.
If these symptoms occur, it is advisable to consult a qualified technician or refer to your Kärcher service manual for diagnostic procedures. Attempting repairs without proper knowledge can cause further damage or injury.
Korisnički saveti
- Provjerite kompatibilnost: Always double-check the OEM part number (4.553.268.0) and compatible models (K 7.20MX, K 720MX, K 7.21MX) before purchasing to ensure a correct fit.
- Pažljivo rukujte: The brass and stainless steel components are durable, but the O-rings and seals are delicate. Avoid pinching or damaging them during installation.
- Consider a Spare: Given its critical role and potential for wear, some users find it beneficial to keep a spare control piston on hand, especially for commercial use or frequent operation.
Garancija i podrška
For warranty information or technical support regarding this replacement control piston, please contact the seller or manufacturer directly. Keep your purchase receipt as proof of purchase.
For service and parts related to your Kärcher pressure washer, please refer to the official Kärcher documentation or contact Kärcher customer service.





