Keep in mind the valve only reduces/stops flow. The core sees full system
pressure. Pull it out of the housing. The leak is usually obvious where the
tubes eroded through or the side tanks separated. If you must test, use some
hoses and fittings and connect to a regulated air supply. Pressurize to 20
pi and submerge in water. You will find the leak. Other common leak spots
are the gasket between the core and valve and the bleeder screw breaking at
the head.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
JRodgers
Sent: Sunday, May 11, 2014 10:37 PM
To: vanagon@GERRY.VANAGON.COM
Subject: 88 GL - Rear Heater Leak Test

Have a leak in the rear heater. Made an absolute mess of the carpet and
padding.

I have it out of the vehicle. Any suggestions as to how to  leak test this
thing. The summer/winter valve is new and has been working just fine with no
leaks. Doesn't appear to leak there now.

Open to ideas.

Thanks.

John