So, to make sure I protected the Westy, I asked this list how often the
timing belt should be replaced. Some very kind people told me the Vanagons
do not have a timing belt, they have a chain, which usually  does not need
replacement. Who knew?

They don't have chains either.  The compact nature of the boxer motor puts
the camshaft within inches of the crankshaft.  The crank drives the cam by
direct-mesh gears.  No belts or chains needed.