I have an Allis chalmers 616 hydro riding mower,I believe it must be 1972-or1973 .I am having a problem with trying to start this tractor,everytime I hit the key to start it blows the breaker.I know I have a good starter,I have checked the wiring it is all intact,also cleaned all the grounds and connections.If I jump the solenoid the starter turns ok.I have no Info at all on this tractor,has anyone had experience with this? If so I am open for suggestions. Thanks Robert