Convert clutch-pedal effort into the hydraulic pressure that releases your clutch with the Dorman - First Stop Clutch Master Cylinder CM112865. It drops in as a direct-fit replacement for the 1986-1991 Mazda RX-7 (R2-1.3L), reverse-engineered from the original equipment to install and operate like the factory unit.
- Direct replacement: built to match the original clutch master cylinder on the listed application.
- Precise design: reverse-engineered from the original equipment to fit and function like the factory part.
- 0.625 in bore: inside diameter matched to the application.
- Durable materials: high-grade rubber components compatible with standard brake fluid.
- Trustworthy value: backed by a US-based team of engineers and quality-control experts.
The clutch master cylinder sits at the top of the clutch hydraulic circuit: when you press the pedal, it pushes fluid down to the slave cylinder to disengage the clutch for shifting. A soft or sinking pedal, difficulty shifting, or fluid seepage at the cylinder are signs this part may need replacing — diagnose the cause first, since these symptoms can have other sources. If a failed master cylinder is the cause, this unit replaces it.
Interchange: 18M2118 · M1018 · 23-14108 · 2314108 · M903143 · Q-53108 · Q53108 · 072-8409 · 0728409 · 12208 · 136.45108 · 137.45108 · CM250100 · LMC225 · CM1136 · FB0141400B · FB0141400C · 39821 · CMA39821 · SH5018 · CM119626 · F119626
Manufacturer part number CM112865. Country of origin: Taiwan.
This part cross-references / interchanges with the following part numbers:
18M2118, M1018, 23-14108, M903143, Q-53108, 072-8409, 12208, 136.45108, 137.45108, CM250100, LMC225, CM1136, FB0141400B, FB0141400C, 39821, SH5018, CM119626, F119626
Frequently Asked Questions
What does the CM112865 clutch master cylinder do?
It sits at the top of the clutch hydraulic circuit and converts clutch-pedal effort into hydraulic pressure sent to the slave cylinder, helping disengage the clutch so you can shift.
Which vehicle does it fit?
It is a direct-fit replacement for the 1986-1991 Mazda RX-7 with the R2-1.3L engine. Check the "Vehicles it fits" section to confirm fitment for your vehicle.
What is the bore size?
The inside diameter (bore) is 0.625 in.
What fluid does it use?
It includes high-grade rubber components compatible with standard brake fluid. Refer to your vehicle's service information for the correct fluid specification and level.
What are the signs it may need replacing?
A soft, spongy, or sinking clutch pedal, difficulty shifting, or fluid seepage at the cylinder can indicate a failing master cylinder. Diagnose the cause first, as other parts can produce these symptoms.
