After almost 6 months at the panel beaters, I finally got my 1970 CS back. The smile on my dial quickly evaporated when I switched the headlights on and all the smoke got out of the red wire from main light switch to the tail lights.
The repairer denies all responsibility but I did locate broken insulation on the number plate bullet connector shorting out around the fuel tank.
I have removed the LH fuel tank and can see the offending melted red wire disappearing into the vicinity go the left rear pillar. Before I get into rip tear bust mode, does anyone out there have a harness layout diagram or maybe just some words of wisdom for replacing the red wire?
On the subject, wiring diagrams show a 35amp inline fuse ......where the heck is it?
Thanks in advance for your help.

_________________
1970 Mk2
1968 Mk1 project

If it's just the red wire you should be able to replace it in situ by using it as a draw wire to pull a new length through. I'll try to find a body harness drawing but, in the meantime, check the size of the red wire by counting the strands so you can replace like with like.

The harness goes up the C pillar and along the channel beside the roof lining, then down the A pillar to the engine bay. There is a connector near the wiper motor that joins the main and body harnesses. Check the wire from the connector to the light switch as that has probably been fried as well.

There is no inline fuse on that circuit.

_________________
ex-NSW Police 1970 MK II Cooper S
VMCI #43

Thanks for your reply Winabbey.
I was afraid that may be the case. When the smoke got out of the red wire, the insulation adhered to adjacent wires, not enough to compromise them, but I don't think I will be able to use it as a draw wire. Body connector is intact but wires on either side including at the switch are fried.
I was thinking of terminating the red wire before the body connector and re route it on the cabin floor to the boot.

_________________
1970 Mk2
1968 Mk1 project

Just check that your 2 fuses in the fuse box are either 35 AMP Lucas fast blow or 17 AMP AGC continuous. Most of the GJ/speed shop kits supply the AGC style and I have seen so many cars fitted with 35 AMP AGC fuses which are double the rating. Here is a good explanation - http://www.mgtoronto.com/pdf/Tech/fuses.pdf

I doubt you'd be able to pull a single wire through anyway, the loom would be spot taped wouldn't it?

I'd probably run a wire through the cabin and fix it properly come resto time...

_________________
did I tell you that I won a trophy?

The spot taping on my loom has lost most of its adhesion so I reckon it would be worth a try pulling one wire. If it's in the centre of the bundle chances are it wouldn't be affected by the taping anyway. Certainly worth a try in my view.

_________________
ex-NSW Police 1970 MK II Cooper S
VMCI #43

fair enough - just need to do a really good job of tieing the pull cord to the wire and tape it smooth I guess

_________________
did I tell you that I won a trophy?

Are you suggesting there would be an issue if the two became detached halfway through the exercise?

_________________
ex-NSW Police 1970 MK II Cooper S
VMCI #43

I did the same thing due to mixing up the 2 number plate wiring connectors. During repairs in the boot both has got painted black. It had a dead short after a few weeks, once the 2 pack paint wore on the number plate flap pivots.

But I was lucky, it only burnt the red wire from headlight switch to the molex plug on the firewall.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

What was the cost at the panelbeaters I have a 1970 cs

Allen

Mozzie I reckon you could just pull the interior light, then run a new wire starting from there and feed it both ways.
You can't see it, so no real need for it to be taped in the loom.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Might be worth a try, up there for thinking, down there for dancing. Good one Doc

_________________
1970 Mk2
1968 Mk1 project