the process takes hours, not days - does not require high amperage, a 'trickle charge' rate does fine - the electrode will not get dirty, but will over time be eaten away - did you use washing soda/sodium carbonate? about 1 Tbsp per gallon of solution? - are you expecting grease and paint to be stripped? the process works on actual rust only the 'crud' may be an ever thickening layer of converted iron oxide, it should be black, the color will not come off, but "flakey" corrosion will need to be chipped off

here's a sequence: manifold w/ lite rust .... using a funky antique charger that supplies about 2 amps, after about an hour, bubbles caused by current flow .... after a few hours, note the water is dirtier and rust colored ... manifold pulled out next morning [about 12-15 hours total], after fresh water rinse - note the rusty areas have turned black, the rest is unaffected .... and after brass wire brushing

Bill

Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics