1951 pa18 125 batterie ground

I have a 1951 pa18 batterie is positive ground. A friend has a newer cub says his is negative ground when did this change? What do i need to do to update to an alternator.

The electrical system has not changed other than alternator vs generator in the mid to late 70s. B&C has an STC for an alternator.
http://www.bandc.aero/alternatorbossmountforpa-1819stc-pma-1.aspx

Never heard of one using positive ground.

To change over to an alternator, decide on the alternator you want. Install it as per manufacturer's instructions. MAKE SURE THE BATTERY NEGATIVE TERMINAL IS TIED TO AIRFRAME GROUND! Ground test and flight test to make sure the voltage is set correctly and the current draw is correct.

B&C and Plane-Power both make good STC kits, so check them out and decide. You also have the option of installing a belt driven alternator or a gear driven style (uses the vacuum pump drive pad). Use new wire and new breakers and master switch.

Web

use a meter and make sure battery isn't charged backwards....

i wondered about ground being positive. Tractors that age were positive ground but were 6 volt. plane was recovered when i bot it maybe they put it wrong terminal.

thanks for input got problem solved.

Markpa18125 said:

thanks for input got problem solved.

Click to expand...

and it was????????

Maybe Lucas electrics on a Cub-- "positive earth"?

batterie cables hooked up wrong. decided to go with plane power alternator conversion. Regulator was smoked.