No lights, no working tach.

[BlazinC5]

So I finally got the 75' JDX8 back together, enough to fire up. Redone the engine and carb after sitting for about 20 years. One of the other known problems i remember from 20 years ago was that the voltage regulator went bad. Headlight got very bright then blew all the lights out. So I replaced the regulator. Well, what I didn't know was that the tach no longer works and have no power to the new headlight. Engine starts easy with a light pull on the rope. Only found one fuse under dash bezel. Its good. What ya'll think it might be? Tried flicking toggle switch, dimmer switch, tapped on key switch. Can't find any broken wires either. Any ideas?

[jep_800]

I had the same problem with my voltage regulator, so the new one did the trick. If you're still having light issues, have you checked if they are all connected properly? There's quite a mess under there, so I'd double check the wiring diagram. Sure you don't have a grounding issue? Next would be to start checking all your connections with a volt meter and reference the manual to make sure it's within spec. Kinda gets to be a process of elimination.

[BlazinC5]

That's kinda what I was thinking was a bad ground. I been looking over the wiring diagrams and can't see anything that jumps out showing where the problem could lay. Out side of the ground wires, I did notice that there are 2 wires, both green/yellow coming off the stator. They appear to not have anything to do with the acual ignition system, and everything to do with the rest. And if that part failed,, well, I guess that would explain why both the tach. and lights don't work while the ignition does. So now i will research about testing the stator too..

[jep_800]

I'm glad you mentioned that. I'm nearing the end of my rebuild, and I changed my stator when I put in crank seals. I remember those two green/yellow wires that come from the trigger housing. The stator came with new connectors for the wiring harness end, so I removed the old ones from the female end and installed the new ones. I remember wondering if I got them in the right slot or not. So, that may be the first place I look if my lights and tach are not functioning when I put it back together.

[JDT]

The green/yellow stator wires are interchangeable.

With the engine connector unplugged check the resistance from either g/y wire to ground. If is open you have either a bad coil or the ground connection on the coil is bad.

[Steven Rempel]

this might not help but I had a issue very similar to what you are having and the only thing that fixed it was cleaning every connection and get all the tarnish off. it was the only thing that was stopping the lights from working, just too much oxidation and tarnish on the male and female connectors. its time consuming but it might help. just a thought.

[BlazinC5]

So,, I haven't had the time yet to check every thing. But, I was messing around with the wires, looking them over, decided to check the switches first. Key switch had continuity on proper terminals. Pulled the light switch,,, well, there are 5 terminals on it. 3 more than i anticipated... Continuity? Not a one. Huh?!?!?! Then I dropped the dang thing on the concrete. OOPS,, Hey,, look at that. Continuity on 4 of the 5. Best part,, I now have lights. Bad part, still no tach working. The non continuity terminal has 2 brown wires into it, don't know where they go yet, or what they do.
The yellow wire with the fuse to the tach has no power coming through it either. I am at this point assuming that, that may be the issue with the tach. No power on that wire. Time to trace more. The wiring diagrams I can find are so far loosely correct to my application. I was hoping to get the tach working so I know my rpm for timing the ignition. Luckily I have a backup. A hand held rpm gauge I can stick on the end of the crank. Pain in the butt, but will work if I can find it in my mess. The engine runs well after the rebuild, (half hearted pull on rope, cold even, fires right up.) But I'm full retard on timing. Tach would just be easier to do timing. Still stoked I have lights now. Thanks for the suggestions and or advice/knowlege guys. I truly appreciate it. Keep it coming.