Hi am currently in the process of rebuilding a 2.1 from my 1990 westy. Am ordering parts from Boston Bob who is also very helpful with technical support. (would highly recommend him to anyone undergoing major engine repairs.) My question to the list or to Bob Donald would be after dipping the case halves into a cleaning tank and then wire brushing them is there a good cleaner to get the aluminum to shine like new.I have got it looking pretty good but there are some dark spots that wire brushing won't get rid of.Does anyone know if the cases are aluminum or magnesium or a combination and are there any cleaners out there that would work ?
Jeff  1990 westy