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An interesting electrical fault caused some lost sleep!

Here's one for the electrical gurus out there.

Monday I fire up the beast and head down to get a few things at the store. Car is perfect, runs like a dream.

I back the car into the carport in front of the garage and walk away for a few hours to do other things.

Around 3pm I come out to put the car away in the garage and she won't go!! Cranks fine, plenty of fuel, no spark!

After lots of issues, looking for neighbours to push etc, I hook up three batteries with jumper cables and gently reverse the car up the slight slope and into the garage using the starter motor.

Te car has an alarm, of unknown origin, and the first though is that the alarm has failed and the ignition curcuit is cut. I strat looking for the alarm box and ended up removing the console, all central guages, both sides of the forward console and still couldn't find it.

After some hours I was able to identify which wires were factory and whch were not, and track them to the alarm box which had been stuffed up behind the rotary fan drum of the heater unit.

The alarm had a manufacturers name and after tracking down the instalation instructions for the alarm, I find that it only has a starter lock out, not an ignition cut. Looks like this isn't the culprit.

Next morning I start testing everything and all indications were that either the MSD 6a or the big Accel coil may have died.

Some hours later, and now armed with lots of test data from MSD and Accel, i go back to the garage and start testing individual components, closely following the written manufacturers instructions.

No matter what I did I got no joy, so the next step was to remove the units and send them off to a local ignition specialist to be bench checked.

One of the previous owners had fitted a few aftermarket goodies. As mentioned, a large Accel coil, MSD 6a ignition amplifier, MSD tacho module, and a different regulator for the alternator.

Let me be kind and say that whoever did the work, their strong suit was not auto electrical!

Nearly everything was connected with these strange winged screw on plastic joiners. No solder or crimp connectors. Yards of plastic tape and hundreds of cable ties. For some obsdure reason, the coil had been mounted siddeway, and on only one bolt, the MSD 6a and tacho modules were screwd to the inner guard, so the sharp ends of the screws were pointing at the rear tyre. You couln't get the inner guard out because there wasn't enough length in the wires going to the MSD 6a unit.

Most birds would be proud of the nest in there!

Anyway, once I got it all out and checked, the ignition shop call back and tell me that it's all fine. I then check the resistance out of the dizzy, and it too is perfect. It's a billet MSD distributor also.

Wondering where to go next, and getting pretty thin on ideas, I decided to pull down the dizzy for a look.

Low and behold, when I removed the cap, the little carbon nipple inside that contacts the rotor button was gone! Just the brass retainer was all that was left, and the sprung contactor on the MSD rotor wouldn't contact the brass, so no spark to any cylinder.

Fortunatley Melbourne has an abundance of good petrol head stores, and after about three hours of hunting, I located a replacement cap. $75 well spent.

So I refitted the dizzy back together but just couldn't put everything else baack the same. It was bloody terrible, and needed sorting.

After getting right up in there, I did some measuring and formulated a plan.

Here's the result:

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