Jim Sower <canarder@frontiernet.net> wrote:
 
>> ... Blowby from
>> compression and/or combustion gasses forcing air into the coolant system ...
>>

> How long would it take a coolant pressure gauge to pick up on that one??
>

   That partly depends on how close your cap pressure is to
the actual operating pressure.  It shouldn't take long at
all for an compression/exhaust leak to raise coolant
pressure to the cap pressure.  So the change in coolant
pressure should be notable.

   An easy sanity check is a variation on Perry Mick's
method, put a go/no-go "fluid level" detector in the overflow bottle (not the recovery tank).  It should normally
be empty, or nearly so.  Exhaust in the coolant will fairly
quickly push some liquid past the pressure cap and trigger
the sensor.  Late 80's GM V-6's commonly use such a sensor
near the top of the radiator tank - I think the current
cost is about $35.00.

Dale R.
COZY MkIV-R #1254