I've done a search online and in this forum, and several people have asked about a white, chalky buildup on Postwar plastics. But it always seems to be on plastic trucks (not bodes) and almost no pictures so I can't really compare my case.
Bought a 1666 loco and air whistle tender on Ebay and overall the loco is in really good shape with almost no real rust and most of its original finish. The E-Unit drum is all melted but the motor is good and even the original wiring with the braided insulation is soft and soldered well.
Took apart the tender and OH MY GOD I thought I was going to have to evacuate my house and call the EPA. I thought this was mold at first, so I immediately washed with mineral spirits and scrubbed the heck out of it with dawn and warm water and a toothbrush. But it only got the worst of the inside buildup off, and no additional amount of scrubbing can remove the rest. And unfortunately it appears to have made the outside finish even worse.
The lettering is still fairly nice with a silver sheen, and I'd like to preserve it if I can. But if the whole thing needs to be stripped then so be it. It'll become another Pennsy Tender.
Photos below, let me know if I should take a hairdryer to it or blast it to orbit.
BEFORE TAKING APART (AS RECEIVED)
REMOVED SHELL - OH MY GOD!
AFTER MINERAL OIL BATH AND DAWN SCRUB: (THE REST WILL NOT COME OFF)
