This is not exactly germaine to Vanagons, but since they have so many black
plastic exterior fittings, it might qualify for consideration.

I just bought a bike with Krauser black plastic saddlebags.  The bike is an
'83, so the bags must be as old.  They are in great condition except for the
top surface of one.  It is a horitzontal surface and all I can figure is that
the bike was parked near a window because everything else shows no signs of
sun damage.  Although the semi-rigid plastic still seems pliant, this surface
has a friable "skin" about 1/64" (about 0.4 mm to you Canadians) deep which
can be sratched off with a fingernail.  I have scraped off most of this
"skin" which comes off in the form of a gray dust and leaves behind a milky,
grayish surface.  I think the bags were treated with Armorall because they
have a sightly oily feel to them.

How can I return this surface to a deep, semi-lustrous black without risking
further compromising the plastic?  Has anyone noticed prolonged use of
protectants like Armorall causing such a problem?

One stange thing is that the lid, which has a pebbled grain texture and, I
would have to assume, is the same material, is like new, even the area
adjacent to the damaged area.

Rich