Logan Savage
Full Access Member
I have two questions concerning the heater in my 2002 3.7 Liberty . First a rundown of what the situation is & what I know . Both heater hoses get hot , about equally so . I flushed & back-flushed the heater core with garden hose pressure & just water . Water seems to flow freely both directions .
I have two Liberty's , this 02 & an 05 , the 05 has good heat . After flushing the 02 & still not getting but very little heat I suspected blend door problems since both heater hoses get hot . The blend door that controls which vents the air comes out works perfectly .
Using a 1 & 1/2 " hole saw I made holes in both Liberty's heater cases to view the heat controlling blend doors . I found that the blend door in the 05 moved farther in each direction than the one in the 02 .
I then removed the actuator for the blend door & installed a manually controlled cable to move the blend door . By viewing the blend door through the hole I made , I can tell the blend door is moving stop to stop using the cable control . I still have very little heat so I'm assuming the problem has to be in the heater core itself .
After flushing the core & finding water flowing freely both ways & both heater hoses getting hot I have come to the conclusion that coolant can flow through the core & bypass the little tubes in it . I sure wish I had an old core to cut open & verify this conclusion . Surely someone has done this or has an old core laying around they could cut open to test this theory .
I'm wide open to any suggestions or ideas that the conclusion I have come to is wrong before I buy a new core & tear everything apart to install it .
The heat gauge in the dash runs about halfway between cold & hot when the engine is warmed up .
All that being said , does anyone know for a fact whether the coolant can bypass in the core & 2nd , does anyone think that the problem could possibly be water-pump or thermostat related or even an air pocket ?
I have two Liberty's , this 02 & an 05 , the 05 has good heat . After flushing the 02 & still not getting but very little heat I suspected blend door problems since both heater hoses get hot . The blend door that controls which vents the air comes out works perfectly .
Using a 1 & 1/2 " hole saw I made holes in both Liberty's heater cases to view the heat controlling blend doors . I found that the blend door in the 05 moved farther in each direction than the one in the 02 .
I then removed the actuator for the blend door & installed a manually controlled cable to move the blend door . By viewing the blend door through the hole I made , I can tell the blend door is moving stop to stop using the cable control . I still have very little heat so I'm assuming the problem has to be in the heater core itself .
After flushing the core & finding water flowing freely both ways & both heater hoses getting hot I have come to the conclusion that coolant can flow through the core & bypass the little tubes in it . I sure wish I had an old core to cut open & verify this conclusion . Surely someone has done this or has an old core laying around they could cut open to test this theory .
I'm wide open to any suggestions or ideas that the conclusion I have come to is wrong before I buy a new core & tear everything apart to install it .
The heat gauge in the dash runs about halfway between cold & hot when the engine is warmed up .
All that being said , does anyone know for a fact whether the coolant can bypass in the core & 2nd , does anyone think that the problem could possibly be water-pump or thermostat related or even an air pocket ?