[R-390] Some questions?

[N4TUA at aol.com]

Hello Friends,
I have been changing the brown beauties out in the R-390A. I have tested 
these and seem to all be leaky by my testing which consists of applying variable 
DC to one side of the capacitor and with the DC milliamp meter checking the 
current through the capacitor. Is this a good indication of the leakiness?

I use cheap solder wick and have some solder flux called NOKORODE. It is a 
paste in a can. A little of this on the wick makes it really pick up well. My 
question: Is this acid flux? Is it OK to use? There is no indication on the can 
that it is acid. It says (the can) it contains zinc chloride.

Thank you, Collin