9 times outa 10 this is the sign of a cracked head.  I heads ore original even more likley.  The AMC heads tend not to crack internally.  Do a leak down test, better info than a compression test.

> On May 4, 2017, at 10:59 PM, Automatic digest processor <LISTSERV@GERRY.VANAGON.COM> wrote:
> 
> I should add that as per previous posts I've made about this engine,
> after driven a while, the engine will blow compression gases into the
> coolant. The main reason for taking a compression test is to establish
> a base line though even if some loose head nuts are loose, tightening
> them may not change the compression results. i.e. the cooling system
> gets over pressurized after I drive the van for quite a few miles.

Cheers,    

Frank Condelli
Almonte, Ontario, Canada
'87 VW Westy, '00 Kawasaki 250 Sherpa, "98 Ducati 750 Monster & Lionel Trains (Collection for sale <http://frankcondelli.com/trainsal.htm>)
Frank Condelli & Associates <http://www.frankcondelli.com/> - Vanagon/Vanagon Westfalia Service in the Ottawa Valley
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