Not all that uncommon.  I've seen my share of this nonsense.

On 2012-02-13, at 11:00 PM, Automatic digest processor wrote:

> First time I've seen this.  Very deep erosion around the spark area.  =
> Next to the valves.  Between the valves, cutting under the valve seat.  =
> Only three cylinders had it.  The heads had to be junked.  Deep, sharp =
> pitting like, picking like erosion.  About 5mm deep. =20
> 
> I don't have a sure idea what caused it.  Surely it is related to =
> ignition or explosion or something of that kind. =20
> 
> This engine has overheated badly.  One of the cylinders has even melted. =
> =20
> 
> I wonder, if anyone has seen any of this before.  And if any of you know =
> what caused it. =20

       Please note that I will be away from my business travelling from November 01 until April 30, 2012.  Parts orders will be processed although not as quickly as usual.  I will always be available for contact by E-mail.  If you phone your call will be addressed by Greg T. Brown here and he will either call you back or advise you to contact me directly by E-mail. Details of this adventure are on our Travel Blog: http://frankcondelli.com/travels/

Cheers,    
Frank Condelli
Almonte, Ontario, Canada
'87 VW Westy, '00 Kawasaki 250 Sherpa, "98 Ducati 750 Monster & Lionel Trains (Collection for sale)
Frank Condelli & Associates - Vanagon/Vanagon Westfalia Service in the Ottawa Valley
Vanagon Stainless Steel Exhaust Systems
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