I have been doing some powdercoating work on mostly aluminum (some steel and cast iron) parts that come to be very dirty, greasy and sometimes painted. The only thing I have found to remove the "crud" is methylene chloride. This is basically the liquid carb cleaner that you buy at a NAPA store. The stuff cleans great, but it has a couple major drawbacks. The first and most important one is the health hazard of this stuff. The MSDS sheet is here:
The parts I am cleaning are automotive intake manifolds, carburetors and throttle bodies. The main thing that I have had a problem removing from these parts is the carbon/oil/gas baked on crust that forms inside the manifold runners and exhaust passages. The methylene does an excellent job of removing this, but I would like to see if there is something else that would do the job as well. I've tried acetone, lacquer thinner, mineral spirits, and even brake cleaner. None of these even put a dent in the removal of this crud. Does anyone have any suggestions? I would like to keep this in my shop if it is doable and cost effective.
TIA Chris