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MG Midget and Sprite Technical - Then there was the wiring...

What's keeping me back now is the wiring, i've got lots of new electric gadgets like high-torque starter, csi electronic ignition, alternator, electric fan and am planning to hide a stereo somewhere.

The old harness was changed by someone who used the same colour on all the wires, yes all green.

I've got a color wiring diagram to follow, but what do i need to think about. Of course i'm gonna change the ground to neg. But should i scrap the lucas regulator box or what's its called, add a better fusebox and relays? What has you guys done?

Car is a frog, engine is 1275 if that's of any importance.

Thanks
Alex
Alexander Sorby Wigstrom

The regulator box won't be used with the alternator, so you can scrap it, or keep it for hiding fuses and relays in.

If you want to make a custom harness then cover it with period looking wrap it can be very clean.

Or, you can have Autosparks make you a custom harness based on your model + the modifications that you have planned.

Or, you can put in a stock harness and then run new wires for what you are adding.

The stock wire gauge is fine for all of those things you have described, so there is nothing inherently better about modern. The biggest benefit is from adding relays for heavy current items to protect your switches. Adding fuses (one for each relay), and then hiding the bank of relays up, behind the dash, is a very clean way for adding these things without making the car look like too much of a rat's nest of wires and modern bits, if that is what one wants to avoid.

Regarding adding fuses, the main reason for having fuses is to protect against wires chafed and grounded to body causing overheating and fire. A carefully routed harness (with stout protection at every metal edge it passes) goes a long way to preventing any of that. With logical protection, a classic can be run fine with no added fuses. But adding them to previously unfused circuits, and changing to modern blade type (which are slightly more resistant to corrosion / intermittent connection issues) can all add peace of mind.

If you are building a truly daily driver, those things can matter more than a typical, restored and cherished classic which sees little rain or winter travel, or major miles accumulation.


Norm
Norm Kerr

Alex,
I think the case for relays is usually a little over played, I've used my present Midget as a daily, sitting outside 24/7, 365/6, and the only relays are on the added electric cooling fan as the relay was part of the kit and I've an electronic relay type indicator flasher unit replacing the bi-metal original

I've also only one added fuse and that's an in-line for the electric cooling fan as it's wire directly from the battery

I see no problem with adding the odd relay, but not banks of them, or having extra in-line fuses

if all the wiring and connections including the glass fuses and fuse box are all clean, secure and protected then I see no reason to go modern with the fuses or fuse box unless you want to

I've used various classics as dailies for over 20+ years without the need to change the existing original fuse set up or add relays

as Norm has put a wiring harness that is well protected and secured needs less protection of fuses than a worn out harness with poor end connections
hanging loose and going through holes without grommets

you might want a thicker wire to your alternator

my present Midget has a hi-torque starter, uprated alternator, 123 fully electronic dissy, uprated electric cooling fan and H4 headlights all on standard wiring and switches with only the added relay and fuse as detailed above
Nigel Atkins

Alexander, I very much sympathise. I've never liked wiring much but I had to do mine too and it turned out not too bad. I first looked at all the colours I'd need and ordered some wire from an auto-electrical supplier. Then I had the loom out on the work table (very pleasant on sunny evenings)and methodically removed all the bad wiring (some it was domestic house cable!) and replaced the bad connectors. One or two items that I knew I would fit (electric screen washer, electric cooling fan and it's servo and temperature control)required additional wiring. I also fitted an additional fuse box and re-routed a couple of circuits to accommodate my repositioned and different switches. My advice is to be methodical. I found the radio, lots of coffee, cigarettes and a few hand-drawn wiring diagrams when I did not understand the ones in the Haynes Manual helped a lot. Once I had connected everything and made sure everything worked (nearly everything)I removed bits of the loom again and re-wrapped it. Some bits, where I had changed my mind, I re-wrapped in situ.
Nick Nakorn

Alright, think I'll figure something out. Not that much of wiring on these cars anyway. Dad had a Corvette once that I helped him a lot with, now that was a rats nest of wires everywhere.
Alexander Sorby Wigstrom

Why not just pay a hooker $1000 to just kick you in the nutz ...

Google a company called painless, they make auto motive wiring componets, from whole turn key kits to just hooking up light bulbs

Its the direction ill go when the time comes

Prop
Prop and the Blackhole Midget

This thread was discussed between 08/08/2014 and 09/08/2014

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