I used this device to fix one obvious coolant leak (due to my sloppy workmanship regarding not thoroughly removing all traces of Teflon tape on a brass NPT fitting for my hot shower water gizmo).  I then used the pump on the device to raise internal coolant pressure to 10 PSI....and then watched and waited.  After 30 minutes, pressure in system had reduced from 10 PSI to 8 PSI.  So "somewhere" in the myriad of Vanagon and Subie motor conversion is a very small leak.  Nothing obvious, like a drip on garage concrete floor.  I sure wish I had a lift, so that I could go all around with a flashlight and look for weepage.  But this may be the best I can do for now.

Am I giving up too soon?  I tried before sliding and crawling under Vanagon looking for leaks....tough job. 

Potential leak points are under dash for Front Heater, which would be major work to find (dash removal).

Advice, comments?

Rich
San Diego