monolithcabs Posted October 9, 2009 Share Posted October 9, 2009 I have a 77' Yamaha xs360 twin that is certainly having some issues with the electric start. The problem is the wire going from the start switch is going directly to ground without pushing it, I have checked the wiring in the switch and its ok, (I know this because I followed the wire all the way to the solenoid with a meter). I have replaced the solenoid with a known good one and have a spare good one to boot. The symptoms are the same for both. When I jump directly from the positive battery terminal to the starter, the starter spins. There are two small wires going from the bike to the solenoid, one is red, which is the hot side and one is blue which goes directly to the start switch, when I plug them into the solenoid, they short to ground, so my only thought is they are being connected through the small coil within the solenoid. Because the red wire is shorting to ground on the hot side, it shorts the whole system. I carefully went through the wiring and traced where the red wire eventually shorts to ground,it is at the points. Now, if I understand this correctly, one of the points is always referencing ground because it is always contacting cam within the points system, correct? Are points suppose to do this? or are they only suppose to contact when the bike is running? So basically what is happening is, the short goes from the points, through the ignition coils, through the red wire, through the solenoid coil, through the blue wire and finally shorting the whole system out. I thought the start switch was the connection to ground only after pushed and should otherwise never touch ground. I am getting voltage on both sides of the solenoid without pressing the start switch, and nothing changes when I press it voltage wise. Can somebody explain? Maybe this is way easier than I am making it out to be....probably. Thanks! I have the manual and schematic. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted October 10, 2009 Moderator Share Posted October 10, 2009 the contacts do earth out as that is what they are supposed to do, but this is via the coils to complete a circuit and then release it to discharge the primary coil. I'mm assuming that the bike runs ok? The other issue I could suggest is the switch gear is faulty and needs stripping and cleaning/checking. the starter button contacts and engine stop are common and it could be there. did this fault just manifest itself or did you do something to cause it? Link to comment Share on other sites More sharing options...
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