Master cylinder leaking?
I don't know what that "extra" plug might be for. My 66 Barracuda one pot m/c didn't have any other ports. Mine was leaking at the plunger seal so I went with safety over originality and put in a dual reservoir (I have factory KH Discs so that's why different sizes). You should be able to get an original style replacement m/c for your car or it may be a good time to do the swap. Don't forget to bench bleed (I did it after it was mounted) Here's mine.
I don't know what that "extra" plug might be for. My 66 Barracuda one pot m/c didn't have any other ports. Mine was leaking at the plunger seal so I went with safety over originality and put in a dual reservoir (I have factory KH Discs so that's why different sizes). You should be able to get an original style replacement m/c for your car or it may be a good time to do the swap. Don't forget to bench bleed (I did it after it was mounted) Here's mine.
