Bolens 1666. Replaced the engine. Was running fine, test drive and all. Went to use it and again it ran fine for about 75'. Then it started an intermittent cut out. Run - cut out-run-cut out. Died when I idled it down at the shop. Circuit breaker was clicking. Took everything out of the circuit. No power to anything except the ignition switch. One safety switch on the brake pedal and that is good. Unplug the battery terminal on the regulator and the short is gone. Tried another regulator. Same thing. Got a new one - replacement numbers match up. It does the same thing - dead short with ignition switch in the run position. Amp meter and breaker do not show a short out of the circuit. No draw on the batter between battery post and started solenoid terminal. Wires all look good, even stripped the outer housing off so I could get a good look at them. Moved them all around. Every time I hook up the B+ terminal at the regulator the breaker kicks out and back on, out and back on with switch in run position. About ready to pull my hair out on this one. Need some solid advise on where to go or what to do from here.