I had a leaking wheel cylinder in my Morris major so instead of fixing the problem I undid the brake line stuffed it with two matchsticks and some bluetack then attached the bleed nipple over the end of it, it seemed to plug up the hole in the bleed nipple quite well until one day during a hard stop the pressure was too much and the whole lot shot out the end of the nipple and I lost all brakes and ended up crashing that car.