My porter cable cable 18 volt charger don't work, they don't make them any more, if I pin it correct can I use a 18 volt harbour or black and decker charger? Tks

There are places that rebuild Battery packs. If able to solder, you may buy the cells themselves and change out. Manufacturers use different methods for charging, 3rd terminal many times is for thermal detection/protection(keep the batteries from getting too hot. You may get lucky on Ebay.

Found a Boatload here:
https://www.google.com/search?q=port...Address&ie=&oe=

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