I am wondering if the poor heat problems many are experiencing are because of
poor bleeding of the coolant system.  My '91 Temp Gauge reads just above the
white and the heat will fry you out at 17 degrees F ambient.
In the summer I usually forget to open the heater valves myself (you don't
need heat in the summer here).  An air bubble in the core or a gunked up core
(Bar's Leak, etc) will give off poor heat.

Thanks,
Ken Wilford
http://www.vanagain.com
John 3:16
Phone: (856)-765-1583
Shop:   (856)-327-0027
Fax:     (856)-327-2242