The Scag Company manufactures a line of garden equipment called Turf Tiger, which is used for large scale mowing and lawn care. Like other mowers, Scag Turf Tigers rely on gas and diesel powered engines for operation. If the ignition systems on these mowers are faulty, they can blow the ignition fuse and prevent operation.
Your Scag Turf Tiger’s ignition switch consists of a capacitor with two poles. When the ignition key is turned, the capacitor’s poles connect and send an electrical charge to the magneto. Turning the switch to the “Off” position disconnects the poles. If your switch is not properly grounded, it can send too much of a charge and blow the 20 amp fuse. The same can happen if the wiring is damaged or exposed.
The Turf Tiger uses a separate magneto starting system. The ignition’s electrical charge is sent through to the magneto, which is made up of an armature, circuit breaker, flywheel and two separate electrical coils. The flywheel has a magnet on it that, when activated, spins past the armature and creates an electrical charge. That charge is relayed to one of the larger of the two coils, which are made of metal like copper. When the circuit breaker stops the flywheel, the electrical charge goes to the smaller, more potent coil. The charge is amplified and travels to the spark plug. A broken circuit breaker or shorted wires can cause an overload to the fuse.
The spark plug is the end point for discharging electricity for combustion. Your Scag Turf Tiger’s spark plug must have a proper gap setting according to the operator’s manual to ensure that the discharge reaches the fuel vapors. If the gap setting is too close, this discharge may not happen. If the bad discharge occurs frequently or there is damage to the spark plug wiring, the electricity could travel backwards through the magneto and ignition wiring.
There are other systems that run through the same fuse that the starter system does. The engine’s electrical wiring is connected to that fuse on the Kawasaki models, while the Briggs and Stratton engines run the engine adapter through it. If there are electrical shorts or damage to those wires, they could be the possible cause for blowing the fuse rather than just the ignition. Check their negative and ground wires for proper connections. These keep the electrical charge from leaving the electric system.