Geoffry,

       You asked about "performance of diesel vs. gas engines": 

       My '82 vanagon diesel (before it died) could manage about 40mph
       in third gear up any grade on the interstates.  I've passed a
       few vanagons, probably aircooled types, but I doubt they were
       racing.  The newer gas watercooleds seem to motor by me
       uphill at about 50mph.  My top speed on the flat, no wind, is
       64 mph.  It gets 27 miles per U.S. gallon almost every time.

       An article in _VW_Motoring (p.66, August 1989) said: "...the
       power output of the van version...was identical to that of the
       type 2 1.6 litre flat-four petrol motor...The paper figures may
       have been the same, but most who drove the diesel van
       considered performance to be inferior to that delivered by the
       air-cooled engine."  Tested top speed was 64mph.  Half loaded,
       zero to 50mph took 25 seconds.  With a five-speed trans., top
       speed is 68mph.

       You also asked about "diesel specific things to watch out for":

       Watch out for air bubbles in the coolant and an oil puddle on
       the block, just below the head gasket.  Watch out for things
       that have been vibrated to death, like the muffler, air filter
       system, alternator mount, crank pulley.  The plastic air filter
       housing, if damaged by clumsy mechanics, will cost $170 for the
       new part.  Same price for the muffler.  Rod bearings can take a
       beating on these vehicles, too, but you won't hear the knock
       until it's too late.  I always have an oil sample tested for
       wear elements.  It's a very sensitive test-- bearing, piston,
       and cyl. wear can be differentiated.  Diesel truck shops would
       be able to refer you to a lab.  I send mine to Analysts, Inc.
       in Oakland, Calif..  Their phone is 800-424-0099.  Cost was
       $26.35.  They saved me from buying a bad vanagon once.

       Finally, you asked about "how long between overhauls"?

       Well, I estimate my vanagon made it about 180,000 miles on the
       original diesel engine before rod bearing failure.  (The
       odometer broke a few years before the engine did.) But, I
       recall worrying about the engine after 100,000 miles.   There
       was an article in _VW_Motoring_ a few years ago about "The
       200,000 Mile Diesel Transporter", but I haven't read the
       article.  If I can find my index, then I'll post the reference
       to the list sometime in the future.

       Thanks for asking, Geoffrey, and best of luck in your purchase.

       Please post this to the list if you think the information will
       be useful to others.  I am experiencing technical difficulty
       posting to the list at this time.

       Mike