Sorry about the last try at this--my grandson got at this keyboard and
did a number on it! Anyway here goes again.
The shop that did the rad and heater core said the rad was fine, but the
heat core was shot. The best they could do was to put some stop leak
stuff in the core and "hope for the best." It worked great for three
years 'til the other day when I saw some coolant on the floor of the
garage. Couldn't figure the point-of-leak 'til yesterday. The core. I'm
inclined to merely put more stop leak in. Any suggestions?