The Small Engine Shop

Motorcycles => Motorcycle General Topics & Repair. Questions. => Topic started by: smallengineshop on February 14, 2021, 06:53:12 PM

Title: Ruptured Brake Line
Post by: smallengineshop on February 14, 2021, 06:53:12 PM
Most brake lines on a car are made of metal, bent and formed in such a way to fit the contours of the cars body/frame and help connect the brake master cylinder to each brake caliper. However, the brake line must be made of a flexible material at certain points to allow movement of the wheels whether it's up and down for suspension or rotation for turning. Take a look at the brake line in the photo. This brake line is made of a flexible rubber/nylon like material and is an original Ford part from a Ford car manufactured in 2001, and connects the metal brake line to the front right brake caliper. This brake line ruptured after 20 years or use.

The rupture occurred at point B in the photo. Point A and C are where the brake line attaches to brake line support brackets on the car. The end of the brake line closest to point A is where the metal brake line connects. Point E is where the brake line connects to the brake caliper. When I removed this brake line I cut the line at point D and B not knowing at the time I was going to need a photograph of this line. Before I cut the line it was holding together at point B by a few threads because of the rupture.

Rubber gets hard and brittle over time and will eventually fail. Its why tire manufacturers recommend replacing your car tires after 5 or 6 years after the manufacture date regardless of the amount of tread left. The property of rubber changes over time and effects the performance of the part. This is why this brake line failed. It got hard and brittle after 20 years of use and ruptured.

When this brake line failed the brake system lost hydraulic pressure and the brake pedal dropped to the floor when applying the brakes. Braking performance was greatly reduced to the point of being a very dangerous situation. Brake fluid shot out of the ruptured brake line and went all over the front right wheel well. If you keep applying the brakes in this situation eventually the master cylinder brake reservoir will empty of all brake fluid.

If you find yourself in this situation try not to panic. I think most parking brakes on most cars on the road today are cable operated and can be used to help stop your car. Also, engine braking can help slow your car down. Engine braking is when you down shift and allow the engine to slow the car. If you ever apply the brakes and it feels like the brake pedal is dropping farther than normal, immediately pull off the road and stop the car and inspect your brake system. The best thing you can do is regularly inspect your brake lines and prevent this type of problem from ever occurring.

Click on image to enlarge
( Brake Line_small.jpg) ( Brake Line.jpg)