I am going to be changeing the leaking rear heater core in my 87 Vanagon GL. What I need is some tips on doing it correctly. I have checked the archive and did not find much info. Do I need to bleed the entire cooling  system after I do it? or can I just bleed it at the core? If someone could point me in the right direction it would help me greatly. The concept of coolant in my bus is a new thing for me. I am new to the list and this is my first Vanagon.

Thanks, Jamie
87 Vanagon GL (Boo Boo)
73 Westy (Pumpkin)