2003 Heat Issue

Discussion in 'KJ General Discussion' started by chadstoks, Nov 27, 2015.

  1. chadstoks

    chadstoks New Member

    Messages:
    22
    Likes Received:
    0
    Joined:
    Sep 21, 2013
    Location:
    Kingsport, TN
    I'm having troubles getting heat out of the Liberty. I believe the blend door is working fine as I can get temperature variation from cold to hot, but when I have it on hot and run the fan up its hardly any heat at all. This to me points to the heater core. I've tried back flushing, but it makes no difference. I have great flow through the heater core when flushing in forward or reverse, what I'm wondering is that if the passageways in the heater core are plugged would the water come through at all? Is there a built in bypass of some sorts, or does the water have to go in one side and out the other? I want to research all options before I go through the task of changing it. Speaking of changing it, does anyone have a step by step, or manual for doing it?
     
  2. LibertyTC

    LibertyTC Well-Known Member Staff Member Moderator

    Messages:
    7,312
    Likes Received:
    465
    Joined:
    Oct 24, 2008
    Location:
    B.C. Canada
    If you recently flushed, you may have air trapped in system.
    For it to pressurize properly, you got to get the air out, by using the top rad hose air bleed screw.
    Also after it sits all night, the coolant reservoir may have to be filled for a few times, to the cold line.
    After filling initially, did you run it for a while with the cap off the reservoir?
     
  3. chadstoks

    chadstoks New Member

    Messages:
    22
    Likes Received:
    0
    Joined:
    Sep 21, 2013
    Location:
    Kingsport, TN
    Yeah, I've done all that, and both hoses are hot too.


    Sent from my iPhone using Tapatalk
     
  4. megatone

    megatone Full Access Member

    Messages:
    147
    Likes Received:
    0
    Joined:
    Apr 1, 2015
    Location:
    California
    Do BOTH hoses get hot at the same time. If yes, then the heater core is fine.

    If one hose is obviously hotter than the other, you should use a chemical flushing agent. Most auto parts stores sell the flushing chemical, and it ACTUALLY works. Follow the instructions on the bottle for proper cleansing. It breaks down the hard mineral deposits that the coolant creates at the end of it's life cycle.

    Continually 'top off' the coolant reservoir with coolant.

    When my daughter was having heater troubles with her Libby, it was right after a water replacement service. Air was trapped in the coolant system. At idle, there was no heat.....rev up the engine and the heat would come back nice and hot. Let off the gas again and the air would become cool again.