Classic Obsession: You Don’t Want to Find This Inside a Rolls-Royce! | Brakes Part 3

Restoring a Rolls-Royce Corniche braking system means dealing with its highly complex high-pressure hydraulic setup. In this third installment of the brake system restoration, Gary Mavers continues replacing old components, bleeding the system, and inspecting the brake reservoir—only to uncover a shocking amount of contamination inside. This episode is Part 3 of the Brakes Restoration Series, following the removal and replacement of brake spheres, lines, and components in previous episodes. If you haven’t seen the earlier steps, be sure to check them out

After fitting new brake spheres in the last episode, Gary turns his attention to:

• Securing the rear brake system by ensuring all new components are installed correctly.
• Painting & sealing the wheel arches to maintain a clean, manageable workspace.
• Replacing the old brake reservoir hoses with new ones from IntroCar, preventing failure due to age-related deterioration.

“It would be pointless to go through an entire system rebuild only to have an old hose burst and empty out all the LHM fluid. Best to replace everything properly.”

Once the hoses are installed, Gary inspects the brake fluid reservoir—and the results are alarming.

• The reservoir is filled with thick, green sludge, a clear sign of fluid degradation.
• Years of contaminant buildup indicate the system had not been properly maintained.
• Brake fluid degradation means particles can circulate through the system, potentially clogging lines and damaging seals.

Why Does This Happen?

Unlike modern DOT brake fluids, the Rolls-Royce LHM hydraulic system requires meticulous maintenance. If not replaced regularly, LHM fluid breaks down, leading to sludge formation, which can compromise the entire braking system.

“It’s easy to replace spheres, but if you don’t clean out the reservoir, you’re just circulating all this filth back through the system.”

To fully refresh the braking system, Gary meticulously dismantles the reservoir for thorough cleaning:

• Removes the sludge deposits, flushing out the entire unit.
• Cleans individual filters, using blue gasket seal to secure them properly.
• Replaces unavailable seals with newly manufactured IntroCar Prestige Parts, which had been out of production for years.

“This is exactly why IntroCar’s Prestige Parts range is invaluable—they bring back essential components that had been obsolete for years.”

With a spotless reservoir and fresh seals, the system is now ready for fluid refilling and final bleeding.

The Rolls-Royce Corniche braking system is unique—it must be bled with the engine running due to its high-pressure hydraulic design.

Step-by-Step Bleeding Process:

1. Start the engine to build hydraulic pressure.

2. Bleed each caliper in sequence, beginning with the rear.

3. Check for leaks—Gary finds one final pinhole leak, requiring a last-minute fix.

4. Recheck fluid levels and top up as needed.

“Unlike conventional brake systems, you don’t just pump the pedal—this system relies on pressurized LHM fluid to force air out.”

With fresh LHM fluid and no leaks, the braking system is fully restored and ready for use.

With the Rolls-Royce Corniche brake system fully overhauled, Gary’s attention turns to his next project—the Porsche 928 GT:

• Full timing belt service is needed after 17 years.

• Deep cleaning & detailing before mechanical work begins.

• Tracking down the correct parts while working in the United States.

“It’s been put off for too long—once the Rolls is sorted, the Porsche is next on the list.”

Have you ever tackled a Rolls-Royce hydraulic brake system restoration? Share your experience in the comments!

IntroCar is the leading international supplier of Rolls-Royce & Bentley parts, providing specialists and enthusiasts with expert knowledge and an unmatched range of original, aftermarket, recycled, and reconditioned components. We are proud to support Gary Mavers of the Classic Obsession YouTube channel, supplying the essential parts for his Rolls-Royce Corniche restoration projects. While Gary works on a variety of classic cars, his meticulous approach to maintaining and restoring Rolls-Royce models aligns with our commitment to keeping these iconic vehicles on the road.