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Dorman M630986 Brake Master Cylinder
Reliable Brake Master Cylinder for Acura and Honda Vehicles
The Dorman M630986 brake master cylinder is engineered to restore proper brake hydraulics in select Acura and Honda models. Designed with durable cast iron construction, this master cylinder ensures consistent braking performance for your Civic or ILX.
- Constructed from cast iron for strength and durability
- Master cylinder bore diameter of 0.8125 inches for precise hydraulic control
- Two mounting holes for secure installation
- Includes two outlets with M12x1.0 thread diameter for rearward and secondary outlets
- Removable reservoir type for maintenance convenience
Detailed Product Description
The Dorman M630986 brake master cylinder is a critical component in the brake hydraulics system, responsible for converting pedal pressure into hydraulic force. This part features a 0.8125-inch bore diameter, which is essential for maintaining proper brake fluid pressure and ensuring responsive braking. The master cylinder is made from cast iron, providing long-lasting durability under demanding conditions. It includes two outlets with M12x1.0 thread sizes, compatible with standard brake line fittings. The removable reservoir design allows for easier brake fluid inspection and replacement. Note that this unit does not include mounting hardware, brake booster, push rod, reservoir, bleeder hoses, sensors, or mounting brackets.
Compatible Vehicles and Applications
- Designed specifically for Acura Civic and Honda Civic models
- Also compatible with Acura ILX and Honda ILX vehicles
- Ideal for replacing worn or leaking master cylinders in brake hydraulic systems
- Restores proper brake pedal feel and hydraulic pressure
- Addresses issues such as brake fluid leaks, spongy brake pedal, and reduced braking efficiency
Installation Notes and Tips
When installing the Dorman M630986 brake master cylinder, ensure the brake system is properly bled to remove air and maintain hydraulic integrity. Since mounting hardware is not included, retain original fasteners or acquire appropriate replacements. Verify compatibility with your specific Acura or Honda model year before installation. Use proper tools to avoid damage to the M12x1.0 outlet threads during brake line connection.
Quality Assurance and Warranty
Dorman manufactures this brake master cylinder to meet or exceed OEM specifications, ensuring reliable performance and fitment. The cast iron construction provides resistance to wear and corrosion. While specific warranty details are not provided here, Dorman typically offers limited warranties on their brake hydraulic components. Consult product documentation or the manufacturer for exact warranty terms.
| Brand | Dorman |
| Part Number | M630986 |
| Mounting Hardware Included | No |
| Mounting Hole Quantity | 2 |
| Master Cylinder Bore Diameter | 0.8125 |
| Brake Booster Included | No |
| Master Cylinder Cap Included | No |
| Master Cylinder Material | Cast iron |
| Push Rod Included | No |
| Reservoir Included | No |
| Bleeder Hoses Included | No |
| Sensor Included | No |
| Mounting Bracket Included | No |
| Number of Outlets | 2 |
| Package Contents | Master cylinder |
| Rearward Outlet Size | M12x1.0 |
| Reservoir Type | Removable |
| Secondary Outlet Thread Diameter | M12x1.0 |
This part fits 18 vehicles. Search below:
| Year | Make | Model | Submodel | Transmission | Position | Notes |
|---|---|---|---|---|---|---|
| 2015 | Acura | ILX | N/A | |||
| 2015 | Honda | Civic | LX | Automatic | N/A | |
| 2015 | Honda | Civic | LX | Automatic CVT | N/A | |
| 2015 | Honda | Civic | EX | N/A | ||
| 2015 | Honda | Civic | EX-L | N/A | ||
| 2015 | Honda | Civic | Si | N/A | ||
| 2014 | Acura | ILX | Base | N/A | ||
| 2014 | Acura | ILX | Dynamic | N/A | ||
| 2014 | Honda | Civic | LX | Automatic | N/A | |
| 2014 | Honda | Civic | LX | Automatic CVT | N/A | |
| 2014 | Honda | Civic | EX | N/A | ||
| 2014 | Honda | Civic | EX-L | N/A | ||
| 2014 | Honda | Civic | Si | N/A | ||
| 2013 | Acura | ILX | Base | N/A | ||
| 2013 | Acura | ILX | Dynamic | N/A | ||
| 2013 | Honda | Civic | Si | N/A | ||
| 2012 | Honda | Civic | Si HFP | N/A | ||
| 2012 | Honda | Civic | Si | N/A |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.