You need to use some washing soda, try some 20 Mule team Borax. That is what I used and it worked great. Even cleaned the inside of the exaust manifold on my 235. I used some a couple of lengths of 1/2 in rebar for the anode. I was just using a small cheap FLAPS 6/12 volt charger.

"If it ain't Steel it ain't Real"
"Earth the insane aslyum for the rest of the Universe"
41 1/2-ton, a work in progress
68 Shortbed stepside 327/325hp/700R4