How to replace heater core

You didnt list the year make and model of the van but all heatercores are located inside the heater box. depending on the year and model there are some where the dash must be removed inorder to gain acess to replace the core, and some there are panels you can remove and then take heater box apart without removing the dash to gain acess to core. good day. heres a picture to help explain where the heatercore is .this would be inside the van on the pass/side under dash. good day.

Inspect/Replace If it is necessary to remove the heater assembly, the cooling system must be drained before removing the heater core.
When a heater core leaks, a new heater core is installed or the old one repaired.
Heater Housing

• The heater housing is usually under the dash and must be removed to gain access to the heater core.
• Procedures for replacing the heater core vary with the year, make, and model of car. It threfore necessary to consult the manufacturer's repair manuals for the proper procedure for replacement.

The heater housing is disassembled to get to the heater core. Heater Core

• Remove the access panels(s) or the split heater/air conditioning case to gain acess to the heater core.
• Remove the heater coolant hoses.
• Remove the cable and/or vacuum control lines (if equipped).
• Remove the heater core securing brackets and/or clamps.
• Lift the core from the case. Do not use force. Take care not to damage the fins of the heater core when removing.
• To reinstall the heater core, reverse the removal steps.

When the heater core leaks and must be repaired or replaced, it is a very difficult and time-consuming job primarily because of the core's location deep within the firewall of the car. For this reason always leak test a replacement heater core before installation.

If it is necessary to remove the heater assembly, the cooling system must be drained before removing the heater core.
When a heater core leaks, a new heater core is installed or the old one repaired.
Heater Housing

• The heater housing is usually under the dash and must be removed to gain access to the heater core.
• Procedures for replacing the heater core vary with the year, make, and model of car. It threfore necessary to consult the manufacturer's repair manuals for the proper procedure for replacement.

The heater housing is disassembled to get to the heater core. Heater Core

• Remove the access panels(s) or the split heater/air conditioning case to gain acess to the heater core.
• Remove the heater coolant hoses.
• Remove the cable and/or vacuum control lines (if equipped).
• Remove the heater core securing brackets and/or clamps.
• Lift the core from the case. Do not use force. Take care not to damage the fins of the heater core when removing.
• To reinstall the heater core, reverse the removal steps.

When the heater core leaks and must be repaired or replaced, it is a very difficult and time-consuming job primarily because of the core's location deep within the firewall of the car. For this reason always leak test a replacement heater core before installation.

are you sure its the heater core whats it doing i would check few things before digging out the heater core its not a easy task heatercore check thermostat if heater blows warm or cold air replace thermostat make sure you have the controls on correct settings inside of car make sure you have proper water levels in car let me no then ill tell you how to change heatercore

1. Disconnect the negative battery cable and drain the cooling system.
   
2. Disconnect the heater hoses from the heater core inlet and outlet connections in the engine compartment.
   
3. Allowing residual coolant from the heater core to drain. Cap the openings.
   
4. Working inside the vehicle, remove the lower instrument panel sound insulator and look for where the air blows to your feet.
   
5. Remove the heater floor outlet duct screws or clips and remove the duct.
   
6. Remove the heater core cover by removing the attaching screws and clips.
   
7. Remove the heater core cover.
   
8. Remove the heater core retainers and remove the heater core
   
9. Reverse order to install leaving the covers off at first then connect all hoses, refill and check for leaks before putting covers back.
   

not knowing if you have a/c or the engine size il guess it has a/c and a 5.0 engine it takes about 1.5 hours not bad to do. pinch heater hose to core, then remove from heatercore.next remove glove box,now remove the 7 screw holding heater access cover to plenum.disconnect vacuum source,leave vacuum harness atchment to cover,then remove cover.then remove heatercore. to install reverse instructions, hope this is helpful good luck.

changing the heater core in this vehicle is a long and annoying task. I just went through it. You will need to remove the entire dash board in order to access the heater core.Once you have removed the dashboard it isn't that tough. Try to cover the floorboards with plastic or something so coolant doesn't soak into your carpet. Remove the screws holding the heater core to the fire wall, disconnect the intake and return lines in the engine compartment and remove the heater core. Afetr you have removed the old core installing the new one should be easy. Dealerships will tell you that this is an 8 hr job and they will want $500 or more for labor but you can do it in 4 - 5 hrs. A new heatercore will cost around $50. Don't forget to have antifeeze on hand as you will lose some.

1. Low on coolant
2. Air in cooling system
3. Clogged or broken valve leading to core

I believe you have to dissassemble the lower part of the hvac unit under the dash to gain access to the heater core, then disconnect the hoses at the firewall and remove the heater core.

REMOVAL

1. Remove the heater-A/C unit from the vehicle. "Housing Assembly HVAC : Service and Repair" See: Heating and Air Conditioning\Housing Assembly HVAC\Service and Repair
2. Remove the heater core retaining screws.
3. Pull the heater core straight out of the housing.

INSTALLATION

1. Install the heater core into the housing.
2. Position the clips over the heater core tubes. Install and tighten the screws.
3. Install the heater-A/C unit into the vehicle. Under "Housing Assembly HVAC : Service and Repair" See: Heating and Air Conditioning\Housing Assembly HVAC\Service and Repair