Ok, in that case most probably the coolant has long expired and requires replacement. You would need to flush the system before replacement of coolant. One time flushing might not clean the system sufficiently and it would be best to drain out the coolant, refill with water and run the engine till operating temperature.
Drain again and flush. Repeat a few times till the water becomes clean before refilling with coolant.
One way of expediting the process is to disconnect the heater hose or if there are stoppers along coolant pipes and plug in a hose to flush.
Tuesday, July 3rd, 2012 AT 4:28 PM