Dorman M630785 Brake Master Cylinder

Brake Master Cylinder for OE-Style Replacement

This Dorman brake master cylinder is built for specific vehicle years, makes, and models where a direct hydraulic brake replacement is needed. The cast iron body, 1.25-inch bore, and included reservoir support consistent brake pedal response and fluid delivery in the master cylinder assembly.

Part number M630785 is a practical choice for drivers servicing a worn or leaking master cylinder on compatible applications such as Honda Civic and similar fitments listed for this part. It is engineered to match the original design, function, and performance of the factory unit.

Key Features

• Dorman M630785 brake master cylinder for hydraulic brake repair
• 1.25-inch bore diameter for OE-style brake system operation
• Cast iron master cylinder construction
• Reservoir included for a complete master cylinder assembly
• Two outlet ports with 1/2-20 UNF thread size
• New, high-quality materials used in construction
• Fits applications cross-referenced to Centric Parts 130.83001 and Raybestos Brakes MC681

Detailed Description

Dorman M630785 is a brake master cylinder designed to replace the original hydraulic unit on specific vehicles. It uses a 1.25-inch bore and cast iron construction to mirror the factory-style layout, while the included reservoir simplifies assembly replacement. This part is intended for brake system service where the original master cylinder has internal wear, leakage, or inconsistent pedal feel. For buyers searching for a brake master cylinder for Honda Civic applications, M630785 provides a direct replacement option for the listed fitment.

This part cross-references Centric Parts 130.83001 and Raybestos Brakes MC681 for the same application.

What It Helps Fix

• Brake fluid leakage from the master cylinder body or seals
• Soft, sinking, or inconsistent brake pedal feel
• Loss of hydraulic pressure in the brake system
• Brake warning symptoms caused by master cylinder wear
• Reduced braking response from an aging OE master cylinder

Installation Notes and Tips

Replace the master cylinder as a complete hydraulic component and bleed the brake system thoroughly after installation. Verify outlet thread sizes, reservoir orientation, and vehicle-specific brake line routing before assembly. Because mounting hardware is not included, reuse or source the required hardware separately if needed. Confirm fitment for the exact vehicle application before purchase, including Honda Civic brake master cylinder configurations where applicable.

Quality Assurance

This Dorman replacement is precision-engineered to match the original master cylinder’s design, function, and performance on the specified applications. It is manufactured from new, high-quality materials to support durable brake system service.