I've noticed both the '85 and the '87 vans get hot during an extended 
idle.  While this isn't 'good', it may be normal for the 
rear-engined, front radiator wasserboxer.  the frictional resistance 
of pushing the coolant all the way forward and back may be too much 
for the waterpump at idle.  

at idle, it seems the engine temp guage will go high but not into
the red zone before the fan comes on.  once the fan does come on, it
doesn't stay on very long before it turns off, even tho the engine
temp is still high.  this is telling me that we a have a design flaw
more than anything-- too far to push the water to have good
circulation at an idle.  the temp of the water returning from the
radiator seems to be within an acceptable range, it's just not
moving enough of it.  raising the engine speed DOES cool down the
engine.

old Fiats used to come with a throttle lock, so one could lock the 
engine at whatever speed one wanted.  didn't make too good a cruise 
control but it sure was nice for cold mornings and a Weber that liked 
it hot.  maybe wasserboxers need a bit of that technology.

now, all you air-cooled people just keep quiet and be nice...  :)

-dan