Re: '49 electrical - 6V ?s

Posted by HH56 On 2013/7/31 20:46:55

Most of us have been replacing original coils with universal 6v coils from Napa or other parts stores. Napa has the Mileage Plus brand for around $17 and a better Echlin for $27. I'd be suspect of any used coils and surely not a 12v coil if you are going to run 6v. The 6v spark is weak enough as it is. The 6v coils are fed directly from the ignition switch and has no resistor with them.

Most important is to get large good quality battery cables - 0 or 00 gauge - for 6v. If using too small a cable, when trying to start the car the battery voltage available to the rest of the car is low. If it drops too much and the coil gets below about 5v when cranking, the spark may be too weak to fire reliably.

The original trunk light had a mercury switch inside & later ones had a steel ball which rolled and made contact. Both types were closed when the trunk lid was raised. Light is powered off the tail light circuit so only gets power to switch when parking or headlights are on.

Schematics showing the light are on the 3rd or 4th page of the 22nd or 23 series (depending on which you have) wiring diagram showing rear body details.