I just bought this 1981 F150 straight 6 for a work truck. It runs great. The brakes were really soft so i bled them. brakes work well now except I keep leaking fluid from the reservoir cover. When i have the cover off and press the brake peddle down, the front of the master cylinder shoots brake fluid out like a water fountian. the larger one in back does not. why is the fluid shooting out like a water fountian?