Gents,
I have an off-topic question. Off topic for Listers that is, but it IS an engine question, and I figure some of you guys know more about this stuff than I do...
So - I'm building a Jaguar V12 racing engine. This has an ali block & heads, and cast iron cylinder liners. The engine I'm rebuilding is 38 years old, so there's obviously a lot of crud around. My big parts washer plus some seriously concentrated degreaser + lots of elbow grease has shifted the bulk of the oily contaminants, and the actual portion of the heads which sees combustion have cleaned up very well. However, the part of the head that's in contact with the water, has heavy rust (iron oxide from the liners & other steel/iron parts of the engine) deposits seriously well bonded to the aluminium surfaces.
My question is - what's the best way to shift the rust without damaging the aluminium? Scrubbing with a plastic scrubbing brush has very little effect. I've had some luck using a Dremel & brass wire brush, but it's very slow going (and the brushes disintegrate rapidly).
The heads are (a bit like early Lister heads) almost impossible to obtain except at ridiculously high prices, so I need to clean them without wrecking them. I'm thinking a decent brass wire brush that I can attach to an angle grinder would be the quickest way to remove it - if I can find a suitable brush of course. Brass-plated steel is no good as the steel will score the aluminium, which means it'll need surfacing, and that buggers up the timing (OHC engine).
Any other suggestions warmly welcomed.
Ta!