In a message dated 98-03-11 17:14:18 EST, mjd@NTR.NET writes:

<< This morning when I started my '81 Vanagon L, I noticed a foul smelling
 smoke coming from under the vehicle. It appeared to be coming from a
 bulbous fixture just in front of the rear axle. It smells vaguely like
 burning rubber. I've noticed that this only happens when I turn on this
 small knob next to my regular heating controls. It has a small green
 light inside of it and it can be pushed in and turned so that it appears
 to behave like a timer of some sort. I know I probably sound like a
 gibbering idiot who never should have bought something I didn't fully
 understand, but I already love my bus and I'm determined to get it
 working properly so that I can take some trips I've been dreaming of for
 a long time.

 Any help appreciated,
 Joe Denison
  >>

Well, apparently you don't know your van has a gas heater.

it is an Eberspacher BA6 model.  it was an option on vw vans, mostly on the
aircooled models.  they need periodic tune-ups.  NO NOT touch that green knob
again until you have it looked at. the gas heater is NOT a part of the stock
heating system, so you can still use your stock heat without a problem.
when functioning properly, the gas heaters are very reliable, and produce a
substantial amount of heat, over the stock heater box heat, in almost no time.
it is basically a gasoline fired furnace, that is located in the middle of
your heater tube, underneath the center of the van. it should be covered by a
large cover, if it hasnt already been removed. it taps gas out of your gas
tank, so it never runs out of fuel, unlike propane heaters. there are many
safety switches/relays that accompany the gas heater, but it still needs to be
serviced to ensure it is safe.

chris