I dropped my '88 Westy in for some work today.
I had noticed a slight coolant loss and gulped when I added about 300 mls of
coolant to top up the tank.  This in about
5000 miles.
I asked for an analysis of the coolant for combustion gases and I also asked
for a compression test.
Now this company has done work for me before and already had 2 other
Vanagons in the shop.
The service manager stated that there was no way that exhaust gases could
leak into the coolant "in this engine".  OK, I thought, I do not think that
is true, so I asked him to locate the source of the leak.
He called back later and advised that the compression was around 85 per
cylinder.
This is an engine with 233,000 on it, with a good rebuild at 160,000.
Starts first time, runs cool and quiet and uses no oil at all.
I checked the archives and noted readings of 140+ as good.
He also advised that there was slight evidence of coolant residue around the
bottoms of the heads, but that a pressure test indicated no leaks.
I am wondering if (a) my mechanic is as good as he might be, and (b) the
compression readings he got were bogus?
Geoff Thomas