Brake hoses – emergency repair advice

Brake hoses can fail in ways that don’t seem to make sense. The rubber hoses that go between the brake cylinders and the steel brake lines can fail. The funny thing is that they don’t always fail by leaking, as you might expect. They often fail internally by deteriorating in the presence of the brake fluid and a piece of rubber ends up plugging the hose. When this happens, more likely than not, the brake drum will seize and the wheel will lock up. It turns out that the pressure from the master cylinder will go past the blockage and expand the slave cylinder. The little piece of rubber will prevent the brake fluid from going back in the other direction, so the brake stays on. For an emergency repair when you’re out on the road, to fix this you need to disconnect the rubber hose from the slave cylinder. To keep the brake line from leaking brake fluid you must pinch off the steel brake line with large pliers (mole grips are best). If you squeeze the steel tubing flat for an inch or so and then fold it back a couple of times, the line will not leak.