diode

hello everyone I am almost finished with wiring on my series 6 and have one last obstacle! There was a short piece of wire about 3 inches long that came with my key ignition! It had one larger eyelet and one smaller and a diode in the middle. I put this on the positive side of the shunt and then to ground. Has anyone else encountered this? If so am I correct?

Thanks in advance
Patrick Series 6 builder

Patrick,

That diode is intended to bridge the coil of your starter solenoid/contactor. If your contactor has 2 coil terminals, it is connected across them. If your contactor has only one coil terminal then the other side of the coil is internally attached to the battery side of the contactor. In that case the diode goes from the large battery side stud of the contactor to the coil terminal. In either case you must be sure to install the diode with proper polarity. The purpose is to protect the start switch from voltage spikes, which can sometimes be several hundred volts, when the coil is de-energized & the magnetic field collapses. This can cause severe arcing & erosion of the switch contact points. Your master solenoid should also have a diode to protect the master switch. The anode, which is the positive (+) side of the diode actually goes to the ground side of the coil. The cathode (-) goes to the battery side - the diode will usually have a stripe around it on the cathode end. I hope this helps.