Capacitor on bore pump burnt out what can cause

a capacitor is nothing more than silver paper raped in plastic in a coil stufted in a can,a cheep one can be + or - 50% of what it sayes it is there is a potassium fluid as an electrolyte in side the can only if its a big one though! if you get to much ripple on the line this will blow the cap....or they just get old and pop off, they will pop off if you overload them as well, there there to sock up ripple's on the line and smooth out the flow of power, in a car they act as an electrical shock absorber and they help to recharge the car ignishion coil faster this also stope the points from burning by stoping the arking,,,