how to back flush a heater core?

Its not very hard to back flush heater core.

On the fire wall of the engine compartment you will find 2 rubber hoses connected to 2 Brass or Aluminum pipes that stick out of the engine firewall, loosen the clamps and remove those hoses, one hose and pipe is smaller than the other hose and pipe, force water with a garden hose through the smaller pipe to "backflush the heater core. 

For procedure regarding

HOW TO REPLACE A HEATER CORE.

Click the link below:---

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-heater-core.html

HOW TO REPLACE HEATER CORE HOSES

Click the link below:--

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-heater-core-hoses.html

HOW TO REPLACE A HEATER CONTROL VALVE

Click the link below:---

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-heater-control-valve.html

HOW TO REPLACE A HEATER AND A/C BLOWER MOTOR

Click the link below:---

http://schematicsdiagram.blogspot.com/2011/08/how-to-replace-heater-and-ac-blower.html