Distributor problem

[1950 pilothouse]

I have a 218 flathead. Does anyone know the firing order? Also the is a wire connected to the side of the distributor. Does it go to the coil? If so does it go to positive or negative side? 

[Tooljunkie]

153624

if its still 6v positive ground, then wire goes to + side of coil. 
ignition switch wire goes to - side of coil. 

[1950 pilothouse]

It’s been converted to 12v by the previous owner and the wiring is a nightmare 

[Tooljunkie]

1 hour ago, 1950 pilothouse said:

It’s been converted to 12v by the previous owner and the wiring is a nightmare 

Ok. Im assuming it has an alternator,most likely neg ground,so plus side of coil gets battery voltage and neg side of coil goes to distributor. There is only a couple inches of original wiring left in my ‘51. All the insulation on original wiring rotted off. 
i converted to 12v neg ground myself. Will be re-wiring soon. 

[1950 pilothouse]

It’s 12v positive ground, like I said a nightmare 

[1950 pilothouse]

But yes has a alternator 

[Tooljunkie]

I really see no point in positive ground. Makes current accessories impossible to install. 

[JBNeal]

It was my understanding that from a physics standpoint, electrons flowed more readily from negative to positive poles, so that's why early automotive systems were positive grounded...eventually it was observed that copper conductors deteriorated from electrolysis when charged with negative voltage, so systems were negative grounded to apply positive voltage to the conductors, which helped protect the copper...

[Jim G]

14 hours ago, 1950 pilothouse said:

I have a 218 flathead. Does anyone know the firing order? Also the is a wire connected to the side of the distributor. Does it go to the coil? If so does it go to positive or negative side? 

It 'should' have the firing order cast into the top of the head, (or is that just a thing done on the Canadian 25 inch ones?)

[tanda62]

The firing order should be 153624

[Jeff Balazs]

When I have had situations like this involving nightmare wiring I have found that it is simply better to tear it out and start from scratch. Wiring one of these trucks is a pretty simple job. There is plenty of info on this site. Spend some time planning it out and it will be pretty painless. When you do this you will end up knowing and understanding the entire system. You can easily switch it over to negative ground during the process.

 

Jeff

[50mech]

Either way it goes to the coil and if you still have points the polarity shouldn't matter as long as one side is neg and one is positive. So your ign wire must be showing negative and on one side of the coil and the positively grounded dist wire must go to the other side.