On Sun, 19 Nov 1995, Dieter Dworkin Muller wrote:

> One thing I noticed and forgot to mention in the Gerbil update is an
> oddness in the rearmost cooling tin.  This is the piece that the fresh
> air tubes go through to connect to the heater boxes, and is on a level
> with the rear deck... [snip]
> In any case, in addition to the two holes for the fresh air
> ducts, and the half-circle things that go fit up around the heat riser
> tubes, are two more holes.  They're about two-thirds the diameter of
> the fresh air holes, and are slightly to the rear (FIF) and closer to
> the midline than the fresh air holes.  Any idea what these might be?

There are, on some early buses and bugs,  air preheater hose that runs from
the oil bath air cleaner   through the piece of tin you mentioned with the
wierd holes, to the hot air blown out under the motor (between lower tin and
cyinders).  The hose is somewhat smaller in diameter than the fresh air
hoses.   Sometimes there is a connection to the muffler.   I know that 67
bugs came with an air cleaner that has two hoses leading off it.   

The pre heat hoses help prevent icing up of the carberettor,  and are a good
thing, along with unplugged heat risers and properly connected and
functioning thermostats.

clara's two cents