Jeff,

The rear heater cores are known to leak after a time.  But ... it could
also be a leaky O-Ring between the valve and the core or even a leaky
valve itself.

When the engine is warmed up and the cooling system is pressurized,
wiggle the hose that goes to the valve a bit and see if that's where
your leak is before changing the core.

Mike

Jeff Clayman wrote:
> I have an 87 2wd westy 2.1.
>
> I smell a sweet smell coming out of the rear heater core when the fan is on.  Do these things rust out or crack?  Are they made of aluminum?  Should they just be pulled and replaced ?
>
> Thanks,
>
> Jeff
>