scratchy wah - pot change does not help

[crane]

Hi guys!
I'm not much of a wah fan. Never owned one - not my cup of tea. But some of my friends gave me two to repair. One used to go silent randomly. Turned out to be a cold joint - easy fix. BUT both of them have some scratching noise when being "pedaled". Is that normal? Tried to replace a pot for one of them (and it's one hell of a pot for 15euro I have to say). No results.
Any ideas?

[Seljer]

Try replacing the capacitors in front and behind of the potenciometer. They might be passing DC causing the scratchiness.

[smallbearelec]

The comment about leaky capacitors is a possibility. While I don't know what make you bought, this FAQ from my site might also apply:

Q: My Dunlop/Black Top/ProPot has gotten scratchy. Can I quiet it down?

A: All of these pots, as well as the SBE Black Bear, are variants of an industrial pot that was developed originally as a joy-stick control. Based on a lot of anecdotal evidence and testing by some SBE commercial customers, we conclude that the lubricant that the maker puts in these picks up dust in some environments, and that sometimes makes the pot noisy.

The present version of the Black Bear is deliberately made without that lubricant. So far, we have not had complaints of shortened life, or of scratchiness. As for the other types, the scratchiness almost always disappears if you diasassemble the pot completely, wash the parts thoroughly with Deoxit or similar solvent, and reassemble.

[crane]

I measured DC voltage on pot terminals 1 and 3 and it was about 4.5V - I figured this IS a DC issue and added extar capacitors in series (I didn't want to change the original caps because they are smd. not sure about the value although it should be 220nF). This helped for one pedal. The other probably does have a bad pot.
Thanks a lot for the advice