Product Description
The Bendix 2512059 Hydrovac Brake Booster is a Fourth Series single-diaphragm vacuum/hydraulic brake booster designed for older commercial vehicles equipped with vacuum-assisted hydraulic braking systems.
The Hydrovac uses engine vacuum to increase hydraulic braking force, reducing driver pedal effort while providing the additional brake assist needed by medium- and heavy-duty commercial vehicles. The 2512059 features a 12-3/4-inch diameter diaphragm housing and measures approximately 17-1/8 inches overall.
This configuration uses a 1/4-inch inverted-flare hydraulic input, 7/16-inch grommet-style hydraulic output, 3/4-inch air-cleaner connection, and 1/2-inch NPT vacuum supply connection. It uses an MB-1 mounting bracket and End Cap J.
The 2512059 is particularly associated with older International/IHC commercial trucks and school buses. Period application catalogs show it in International 1600, 1610, 1700, 1703 and 1800 school-bus configurations, including systems using two Hydrovac units with a split master cylinder. Because several Fourth Series Hydrovac boosters look very similar, verify the original part number, hydraulic connections, mounting bracket, and overall dimensions before ordering.
Part Number: 2512059
Reman Reference: RV2512059X
Brand: Bendix
Product Type: Vacuum/Hydraulic Brake Booster
Series: Fourth Series
Design: Single Diaphragm
Diameter: 12-3/4 in.
Overall Length: 17-1/8 in.
Hydraulic Input: 1/4" Inverted Flare
Hydraulic Output: 7/16" Grommet Style
Air Cleaner Connection: 3/4 in.
Vacuum Supply: 1/2" NPT
End Cap: J
Mounting Bracket: MB-1
Core Group: VAC1004
