Wiring query

[vintagevulture]

Hi,

can anyone offer some ideas please? I have an interesting electrical issue, over 35 years of re-building Morrises and cannot seem to sort it.

1098cc late car, re-wired with original type Autosparks loom. Everytime I connect live terminal on battery there is a flash, as though something is drawing a current. Regulator appears to be heating up. So far I have only connected up to test individual circuits but must be missing something.

Tried so far.

2x regulators, new with contacts cleaned. (earths double checked and connections in correct sequence)
Vehicle is wired positive live negative earth with electronic ignigtion -ve type.(I re-polarised it and flashed the small wire on the dynamo.
Horn works
Interior light works
Indicators work (IGNITION ON)
Dip headlights work/ mainbeam not working as yet
Sidelights work.
Brakelights not working (not tested as yet)
Power to coil and electronic ignition appears to function.
Fuel pump works with ignition on.
Wiper motor not working/untested at the moment.
I have not tried to start vehicle as yet due to checking all the other connections first

Apart from checking connections/bad earths etc Can anyone point me in the right direction?

Many Thanks

John

[oliver90owner]

Most regulators are wired for positive earth. Some can be changed, some may not. Most cars are converted to alternator when the polarity is changed to negative earth, so effectively do away with the regulator.

[simmitc]

Perfectly reasonable to convert a dynamo to -ve earth, retaining the regulator; been done hundreds of times.

First thought is a hot regulator suggests that wiring is wrong and you are trying to use the dynamo as a motor, thus drawing current - disconnect the dynamo and see if spark persists. After that, although you have spent time connecting everything, I suggest disconnecting it all and then checking for your spark. If it still occurs then you need a multimeter set to resistance and then check for a short on every circuit. Obvious question is why the main beam does not work? It sounds like a short to earth.