* Wheel Cylinder: This is the most likely culprit. The wheel cylinder is a small hydraulic cylinder located inside the brake drum (if you have drum brakes) or behind the caliper (if you have disc brakes, which is more likely on a Mark VIII). It pushes the brake shoes (drum) or caliper pistons (disc) to apply the brakes. A leak in the wheel cylinder will result in brake fluid escaping.
* Caliper: If your Mark VIII has disc brakes (most likely), the caliper is the more likely source of the leak. The caliper contains pistons that squeeze the brake pads against the rotor. Seals within the caliper can wear out and leak brake fluid. A seized caliper piston can also cause a leak.
* Brake Hose: The flexible brake hose connects the brake line to the caliper (or wheel cylinder). If the hose is cracked, perished (worn and brittle), or internally damaged, it can leak. This is less likely to be the *only* source of a leak, but often accompanies other issues like a bad caliper.
* Brake Line: While less likely than the other components, a rusted or damaged section of the rigid brake line leading to the wheel could also be leaking. This is less common unless there's significant corrosion.
What to do:
1. Safety First: Leaking brake fluid is a serious safety issue. Do not drive the car until the leak is fixed. A significant brake fluid loss will severely impair braking ability.
2. Visual Inspection: Carefully inspect the area around the wheel. Look closely at the caliper (if it has disc brakes) or the area around the wheel cylinder (if it has drum brakes). Look for wet spots, staining (brake fluid is typically dark and oily), or visible cracks in the hose.
3. Professional Diagnosis: Unless you have significant automotive experience, taking your car to a qualified mechanic is strongly recommended. They have the tools and expertise to diagnose the precise location of the leak and make the necessary repair. Attempting a repair yourself without the proper knowledge could worsen the problem or lead to injury.
Replacing a wheel cylinder or caliper is usually a relatively straightforward repair for a mechanic. Replacing a brake hose or brake line might require more specialized tools or techniques, depending on the location of the leak. Regardless, prompt attention to this problem is crucial for your safety.
