78 spider electrics

[MrBlimp]

I just spent over 10 hours on the electric system in my newly acquired 78 Spiders.

I ran a series of tests a few days ago using my Fluke multimeter and found that there was current all the way to the sockets. But, the not all of the tail and parking lights were working. Plus my headlights and high beams were not both working.

So I attacked it today.

I removed both of the tail lights. Then I drilled out the rivets holding the socket/receptacles to the back of the light fixture. I disassembled each one (two pieces of plastic, a steel element that the wire connects to, and a springy brass element that connects to the steel one which makes the contact to the center of the bulb). Then I thoroughly cleaned every bit of all eight sockets and the ground system (I used some sandpaper and a plumbing wire brush used for cleaning the insides of solder joints). I reassembled the sockets using screws as replacements for the drilled out rivets and then assembled the whole thing. Once back in the car the parking lights and brake lights worked perfectly.

Next I removed all the fuses (they were mostly plastic replacement style). I wire brushed all of the fuse holder contacts and inserted new ceramic fuses. The headlights, high beams, and DIP switch instantly worked. And I now have dash lights (working brightness controller) and two speeds on my blower where I only had one, and barely one at that.

Next was the signal lights - the relay was barely working and when I went to check it out I found the case shattered - I have to buy a replacement. I am hoping that is the only issue.

I still have the wiper/washer system to get working before I can get it inspected. I plan to start by removing the cowl and checking the motor.

I also need to get the Tach running - I can't seem to find any documentation on it. The wiring diagrams only seem to show the power to the instrument's lights.

[MrBlimp]

Another 10 hours and everything is working except the tachometer.

Wipers, washer, all lights are A-OK.

Now I have to figure out the issue with the Tach.

[seabeelt]

brown wire from D or neg side of coil to plug for tach then brown/white wire to back of tach ; brown white wire from brown wire also goes to pin 30 on the ignition mode relay (starting/running points setup)