When I first read the post about Larry's engine trouble I emailed and then called him to go over the symptoms and offered him my thoughts and things I would check. 
 the lower end of the current engine does not sound suspect from what I could tell.
the valve train and the head is most likely in need of a good going over and then he will see if he really needs an engine. I told him to keep in touch and have not heard back at this point.
 The melted piston could be from a lean condition or preigition but the preignition tends to blow out rod bearings before the piston melts. On my engines I increase the piston to skirt clearance by honing the cylinders. This is common practice on racing and industrial engines in severe duty applications and I consider the vanagon a severe duty application. Some of you air-cooled types might recall that VW had a tech bulletin on the type 2 and van engine that called for this increase in piston to cylinder clearance. The type 2 engines melt pistons all the time when they are not busy dropping seats 
So I am waiting to hear from Larry about his engine diagnosis 

going faster miles an hour with the radio on 
I remain 
Boston Bob
  ----- Original Message ----- 
  From: Ben 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Thursday, May 06, 2004 3:11 PM
  Subject: Re: Roadhaus....partial solution for helping!

  Mmmmmmm..... good point, but what about the others customers with the same problem!
  Ben

  David Brodbeck wrote:

On Thu, 6 May 2004, The corruptor wrote:

  I think that the crank is the problem, am thinking of a bad rod a alignment
/ faulty and defective main bearing, but now we are getting deap, maybe Bob
or others can comment on my diagnostic. Even the core as been change, so i
also rule out a bad sleeve matting surface,  remember, always the #1 going
out in flame, different case and head, now i don't know if the rods or crank
is the same???
    
If it's always the same piston burning, has anyone thought to flow-test
the injector for that cylinder?  Maybe it's running lean on that one
cylinder.

David Brodbeck, N8SRE
'86 Volvo 240DL wagon
'82 VW Vanagon Westfalia Diesel