You need to remove the coloured deposits, if only to be sure that traces and lands have not been severed or destroyed underneath the deposits. Better to know this at the outset than to rue it later.
Any one or more of the chemical species in the electrolyte, alone or in concert with others.
Which is what may happen if the logic or power/sweep board is powered-up or active while the capacitors are leaking.
It's a matter of concentration as well as pH. A few ppm of something such as chlorine residues (most of the hypochlorite has been reduced as it was acting on organisms or inorganic molecules) is of no consequence, even if you can still smell it. The aim of washing is 'infinite dilution' of the nasties by washing completely one, two, three or more times as needed, and then rinsing several times to reduce the concentration of nasties (which are not being replenished because you have already removed the bung capacitors) to infinitesimal levels. It's an asymptotic approach to zero, which is never reached, but can be approximated. Ordinary kitchen detergents are non-polar. If in doubt, consult the label on the container.
Last 25-odd years: Technical writer/editor. Previous 25 years: Biologist, biochemist, microbiologist, fermentation technologist, biodegradationist(?)—in industry—with a strong dabbling in electronics to use in those disciplines.... 5) Easy one: what's your profession? You know so much about capacitors, I'm lead to believe you make capacitors as your day job
Y' wulcum.
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