Just replace it. You will see the gooey mess when you remove the old one.
For some reason stop leaks so not work well on heater cores unless the
goal is to stop the heat.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Richards, Andrew
Sent: Tuesday, December 18, 2007 5:50 PM
To: vanagon@GERRY.VANAGON.COM
Subject: that sweet coolant smell

Ooooh yeah, my van's front heater smells like maple syrup.  So what's
the problem?  I'm not losing any noticeable level of coolant and don't
see any leaks when I pull the plastic cover off the front blower.  I've
heard heater cores go out, as does a small plastic connector fitting of
some sort (cracks?).  I'm assuming I don't see any leaks because it's
all just evaporating before it can drip off the core.  How do I
troubleshoot this one?

Thanks,

Andrew

'87 GL 160K