GMA Engineering 5/8 Bore Rear Master Cylinder Rebuild Kit for Kelsey Hayes and Wagner Style
A worn master cylinder does not have to mean pulling the unit and sourcing a replacement. This GMA rebuild kit restores the hydraulic integrity of GMA’s 5/8″ bore rear master cylinders back to proper operating condition — bringing back the firm, predictable pedal response that a correctly functioning vintage brake system demands.
Key Features
- Purpose-built for GMA Engineering 5/8″ bore rear master cylinders — covers both the Kelsey Hayes inline (GMA-MC1K) and Wagner offset (GMA-MC1W) styles
- Restores full hydraulic function and seal integrity without full unit replacement
- Verify the top cover dimensions match your GMA cylinder before ordering
Technical Specifications
- Bore Size: 5/8″
- Compatible Brand: GMA Engineering
- Compatible Styles: Kelsey Hayes inline (GMA-MC1K), Wagner offset (GMA-MC1W)
- Top Cover Length: 3-1/8″ (3.125″)
- Top Cover Width: 1-7/16″ (1.4375″)
- Application: Rear master cylinder rebuild
Fitment Notes
- Designed specifically for GMA Engineering 5/8″ bore rear master cylinders — not a universal rebuild kit
- Top cover must measure 3-1/8″ (3.125″) x 1-7/16″ (1.4375″) — verify against your cylinder before ordering
- Not compatible with 3/4″ bore master cylinders
Anonymous –
Item was perfect.
Anonymous –
Exact part, oem rebuild
Anonymous –
Received GMA rebuild kit MCRB-1 which is just what I ordered.