3CX, 4CX (models with P12 cab, non-servo)
The master cylinder is a key component that converts the force from the pedal into hydraulic pressure. In non-servo machines, its failure is particularly noticeable. Symptoms include a "soft" brake pedal that goes to the floor, fluid leaks, the need for repeated "pumping," or a complete loss of brake response. A faulty cylinder is a critical failure that endangers the operator and those nearby.
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Restored Braking Power
"Firm" pedal and immediate response
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Guaranteed Sealing
No leaks and stable pressure
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Complete Kit
Ready for installation
A functioning master cylinder is the basis for effective braking. Replacing it restores the machine's ability to stop safely.
A high-quality replacement that provides reliability and durability comparable to the original part.
Designed as a direct replacement, ensuring a hassle-free and quick installation in older 3CX and 4CX models.
When replacing the cylinder, always use fresh, manufacturer-recommended brake fluid dedicated for JCB machines. Old fluid loses its properties and can damage the new cylinder.
After installing the new cylinder, the entire brake system must be thoroughly bled according to the service manual. This is crucial to achieve full braking power.
Answer: No, this model (15/920110) is exclusively for older machines without a power-assisted brake system. A different master cylinder is dedicated for servo machines.
Question: Why is my brake pedal still "soft" after replacing the cylinder?Answer: The most common cause is improper bleeding of the brake system. Another possibility is a leak further down the system (e.g., in the hoses or wheel cylinders).
If you are unsure whether the selected product is suitable for your machine, contact us and we will help you choose the right part and provide practical advice in minutes.
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