Datsun Roadster Forum-311s.org

Hi, all:

I'm looking for a wiring diagram that has the wire sizes as well as the insulation color patterns. Can't seem to find one on the web.

You see, I did the GM alternator swap yesterday, in my '66. Went real smooth -- even hacksawing the bracket wasn't too painful. As the guide in the tech section suggests, I skipped the white wire entirely, sending the alternator's power directly to the POS terminal on the battery.

On startup, it charged like a top, and everything worked but the headlights and dash lights. The blinker dash indicators were bright enough to see for the first time! But, then I lost the parking lights, blinkers, brake lights and all gauges.

Today, while I was tuning the carbs, the wipers spontaneously started. The switch was off, the wiper motor was hot hot hot. Every other wire, connect, fuse, relay, etc. was completely cool and showed no signs of melt.

Rather than try to diagnose the mess of wires mangled by past owners, I'd like to make an entirely new, clean harness. But, I don't want to guess at what size wire to use. Any suggestions?

Thanks,

Jesse.

Jesse,

Excellent question. What I can see under my dash is a rat's nest; what's under the hood is lookin' mighty decrepit.

The wiring diagrams are here:

http://www.311s.org/tech/electrical/wiring.html

No, they do not specify the wire gauge, but someone must have done this before.

The lines are all one color (red), but they are marked w/ the correct wire colors. I'm wondering how hard it would be to colorize the diagram, and what application one would use: AutoCAD, Photoshop?? Or has someone already done this grunt work?

Wire size is determined by the amperage or current the curcuit will carry. As a base guide

30 amp = #10 awg (americam wire gauge) stranded.
20 amp = #12 awg
15 amp = #14 awg
10 amp = #16 or 18 awg

never use anything less than #18 in automotive wiring. There is a number of different types of wire insulation and # number of strands that mke up a wire. Automotive is usually "xga" or "glx" type wire, which is a very fine stranded super flexable wire.

Hope this helps

Keith,

I'm re-wiring our kitchen and should've known the ampacity vs wire gauge...big DUH. However, I didn't know about the XGA or GLX rating for automotive wire. Kewl.

I doubt automotive wire is any different, so you could probably wire everything (other than the battery leads) with 10-AWG and be fine, right?

Eric used a MAXI blade fuse between the alternator and the wiring harness on his GM alternator conversion. Any reason to use the MAXI instead of an ATC blade fuse?

Thanks.

There are differences between fuse types, ie insta-blow fuses and slow-blow fuses. The important thing to keep in mind tho is the wire size and device you are trying to protect. Any fuse that is sized correctly is better than an unprotected circuit.

I redrew the wiring diagram for 68's in InDesign. Took quite a while!

http://shiftco.com/features/index.html

I would use a vector-based program like Illustrator or Freehand rather than bitmap like Photoshop.

(Steve, do you want to add the file to the 311s.org site?)

Leigh,

Yes, I would like to add it. Thanks.

Steve

Leigh's diagram is sweet. I was redrawing the '66 diagram with color and relative gauge, but wasn't bothering with the tracer. Now I think I should probably start over -- the bar's been raised!

Thing is, I've already finished rewiring the car. Took 14 hours on Saturday and 10 on Sunday, but I had to get it done while my fiancee was out of town. The remarkable thing is that it all works.

When I've finished the diagram, I'll send it to you, Steve.

Best,

Jesse.

Jesse,

Send it on and I will be glad to post it. Leigh did and excellent job on the one he updated.

Steve

Jesse,

Hehehehehe.....I had to wait until my wife went to visit her Dad in San Jose so that I could play roadster mechanic and get the car running again. Now we're back into kitchen remodelling mode.

By any chance, did you make up a materials list of what it took to do a complete rewire? Did you match the original color code and wire sizes?

Thanks.

Hey I would like to know what it takes to rewire a roadster also.