The ignition key barrel has nothing to do with electricity.

This is what you want to inspect:


wiki - Wiring

The ignition switch itself is a separate part & is connected to the ignition barrel at the bottom by a single screw, & they do occasionally give trouble.
They are not only easy to replace, but the swirch itself was common to many Datsun models, so a replacement, either used or new should not be too hard to find.

Early Datsun 1200's used a different switch without an accessory position, so this one might be a bit more of a problem. These earlier switches have [I think] four spade terminals at the base while the later, more common ones have five.

There are many items in a car that is now well over 30 years old that can expire without warning, & can take a while to fix, so for many years I have lived by the following addage.
Buy spares when you WANT them, so you don't miss out when you NEED them.

Like you, I also have a Datsun 1200 DeLuxe Coupe & yes, I have a new switch in my stash, along with a new fuel pump & a whole bunch of other consumeable parts. Parts costs & downtime are kept to an absolute minimum. Plan ahead.

liam_1200_coupe_deluxe
P.S. I grew up & went to school in Northmead. Still have my cadet uniform too.

Alright guys, i replaced the ballas resistor, still having the same problem, however the car drove normally on the way to repco to pick it up, and then again on the way home from the city tonight. i'm going to see how she goes after i change the ignition barrel. If that doesn't work i'll re-check the wiring but it seems all good.

Thanks heaps for your help and suggestions...

ok i went on holidays and pulled a wire off the coil so it didnt get stolen i forgot about it and the car would only run if i held it inbetween no and start might help ya :)

Right on, PIGDOG. Another possibility though less likely is that the wiring to the coil is put on wrong. There is one 'hot' wire for ballast (I) and another goes straight to coil (S).

ballas resistor on the coil dead, so coil only getting full power when in the start position

hey guys, i was recently lucky enough to score a datsun 1200 coupe, but it's seen better days.

the current problem i am having and require some assistance with is:

The car is running like ####! unless... i turn the key just to the start position, so the tacho drops to 0, and then she runs fine!

is it possible that the barrel itself is rooted? or is there another solution that i have looked over?

thanks.