bmwrepairs: How to remove heater core on BMW 2005 325?

Removal & Installation

Disconnect the negative battery cable. Drain coolant from the cooling system. Remove the center console.

Remove the mounting bolts and remove the right core mounting bracket. Lift out the front blower motor on the 7 Series.

Remove the core cover screws. Loosen the wire straps and clips and remove the cover.

Disconnect the temperature sensor(s).

Unscrew the mounting bolts and lift out the heater pipes. Replace the O-rings. Then, lift out the core from the right side.

To install:

Install the core in from the right side. Install the heater pipes with new O-rings, then tighten the mounting bolts.

Attach the wiring connector to the temperature sensor(s).

The remaining components are installed in the reverse order from which they were removed.

Fill the engine with the correct amount and mixture of antifreeze and water. Connect the negative battery cable, then start the engine and check for coolant leaks.

3 Series

NOTE

The heater case assembly must be removed to remove the heater core on all 3-Series vehicles.

Disconnect the negative battery cable.

Drain the cooling system into a clean container for reuse.

Discharge and recover the air conditioning system refrigerant.

Remove or disconnect the following:

Remove the heater bulkhead from the engine compartment

Fig. Heater bulkhead retaining screws
Release hose clamps and detach the water hoses

Release heater case screws on the firewall

Fig. Heater case retaining screws
Steering wheel and column switches

CAUTION

When removing the steering wheel on airbag equipped vehicles, use extreme caution handling the airbag assembly. Store the airbag with the airbag facing up, to avid injury in case of accidental deployment. Replace damaged airbag assemblies. Do not try to repair or reuse deployed airbag assemblies.

Center console retaining screws

All electrical leads and remove the console

Open the glove box and remove the glove box door assembly

Instrument panel trim

Left and right -A- pillar trim

Headlight switch assembly

Instrument cluster

Radio assembly and the radio trim

Ventilation control head

Passenger side airbag

Left and right defroster vents

Upper instrument panel retaining screws and pull the instrument panel away from the firewall

All electrical multi-plugs and pull the instrument panel out of the vehicle

Steering column fasteners and lower the column

Remove the fasteners from the right and left sides of the instrument panel reinforcement

Right and left head airbag assemblies if equipped

Fig. Instrument panel reinforcement side fasteners and head airbag assembly

Electrical leads from the heater

Right and left center console reinforcements

Cut the cable ties from the fusebox. Release the locks and pivot assembly downwards

Fusebox and the transverse reinforcement

Heater case retaining bolts and heater case assembly from the vehicle

Remove the core from the case assembly

To install:

Install or connect the following:

Heater core into the case. Make sure the gasket is positioned properly.

Heater case in position in the vehicle

Fusebox and the transverse reinforcement

Pivot fusebox assembly upwards and engage locks. Install new cable ties

Right and left center console reinforcements

Electrical leads from the heater

Right and left head airbag assemblies if equipped

Right and left side fasteners of the instrument panel reinforcement

Raise the steering column and install new fasteners

All instrument panel electrical multi-plugs and the instrument panel into the vehicle

Left and right defroster vents

Passenger side airbag

Ventilation control head

Radio assembly and the radio trim

Instrument cluster

Headlight switch assembly

Left and right -A- pillar trim

Instrument panel trim

The glove box door assembly

Center console

Column switches and steering wheel

Heater case screws on the firewall

Water hoses and clamps

The heater bulkhead in the engine compartment

Refill the cooling system.

Evacuate, charge and leak test the air conditioning system.

Connect the negative battery cable.

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

3-Series

NOTE

The heater case assembly must be removed to remove the heater core on all 3-Series vehicles.

Disconnect the negative battery cable.

Drain the cooling system into a clean container for reuse.

Discharge and recover the air conditioning system refrigerant.

Remove or disconnect the following:
CAUTION
When removing the steering wheel on airbag equipped vehicles, use extreme caution handling the airbag assembly. Store the airbag with the airbag facing up, to avid injury in case of accidental deployment. Replace damaged airbag assemblies. Do not try to repair or reuse deployed airbag assemblies.

Remove the heater bulkhead from the engine compartment

Fig. Heater bulkhead retaining screws

Release hose clamps and detach the water hoses

Release heater case screws on the firewall

Fig. Heater case retaining screws

Steering wheel and column switches

Center console retaining screws

All electrical leads and remove the console

Open the glove box and remove the glove box door assembly

Instrument panel trim

Left and right -A- pillar trim

Headlight switch assembly

Instrument cluster

Radio assembly and the radio trim

Ventilation control head

Passenger side airbag

Left and right defroster vents

Upper instrument panel retaining screws and pull the instrument panel away from the firewall

All electrical multi-plugs and pull the instrument panel out of the vehicle

Steering column fasteners and lower the column

Remove the fasteners from the right and left sides of the instrument panel reinforcement

Right and left head airbag assemblies if equipped

Fig. Instrument panel reinforcement side fasteners and head airbag assembly

Electrical leads from the heater

Right and left center console reinforcements

Cut the cable ties from the fusebox. Release the locks and pivot assembly downwards

Fusebox and the transverse reinforcement

Heater case retaining bolts and heater case assembly from the vehicle

Remove the core from the case assembly

To install:

Install or connect the following:

Heater core into the case. Make sure the gasket is positioned properly.

Heater case in position in the vehicle

Fusebox and the transverse reinforcement

Pivot fusebox assembly upwards and engage locks. Install new cable ties

Right and left center console reinforcements

Electrical leads from the heater

Right and left head airbag assemblies if equipped

Right and left side fasteners of the instrument panel reinforcement

Raise the steering column and install new fasteners

All instrument panel electrical multi-plugs and the instrument panel into the vehicle

Left and right defroster vents

Passenger side airbag

Ventilation control head

Radio assembly and the radio trim

Instrument cluster

Headlight switch assembly

Left and right -A- pillar trim

Instrument panel trim

The glove box door assembly

Center console

Column switches and steering wheel

Heater case screws on the firewall

Water hoses and clamps

The heater bulkhead in the engine compartment

Refill the cooling system.

Evacuate, charge and leak test the air conditioning system.

Connect the negative battery cable.

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

Removal And Installation

NOTE

The heater case assembly must be removed to remove the heater core on all 3-Series vehicles.

Disconnect the negative battery cable.

Drain the cooling system into a clean container for reuse.

Discharge and recover the air conditioning system refrigerant.

If equipped with an automatic transmission, remove the screw retaining the shift lever T-handle. On manual transmission equipped vehicles, remove the shifter knob.

Remove or disconnect the following:
CAUTION
When removing the steering wheel on airbag equipped vehicles, use extreme caution handling the airbag assembly. Store the airbag with the airbag facing up, to avid injury in case of accidental deployment. Replace damaged airbag assemblies. Do not try to repair or reuse deployed airbag assemblies.

Shift lever cover and pull the window switches out of the console

Center console retaining screws, disconnect all electrical leads and remove the console

Open the glove box and remove the glove box door assembly

Left and right -A- pillar trim. Remove the left and right kick panel trim

Lower instrument panel trim pads. Remove the steering wheel

Steering column trim

Instrument panel -A- pillar retaining bolts. Remove the lower instrument panel retaining bolts at the kick panels

Instrument cluster retaining screws and remove the instrument cluster. Disconnect all instrument cluster electrical leads

Radio assembly and the radio trim

Ventilation control head

Upper instrument panel retaining screws and pull the instrument panel away from the firewall

All electrical multi-plugs and pull the instrument panel out of the vehicle

Refrigerant lines from the evaporator

Cowl cover from in the engine compartment. Disconnect the coolant lines from the heater core

Electrical leads from the blower

Air ducts from the heater case

Heater case retaining bolts from the engine compartment side and the retaining bolts from the interior side

Heater case assembly from the vehicle

Clips retaining the case halves and remove the blower motor cover and motor

Heater core form the case

Fig. Exploded view of the heater/blower housing assembly-3-Series

Fig.

Install or connect the following:

Heater core into the case. Make sure the gasket is positioned properly.

Assemble the case halves and attach the blower cover. Install the blower

Heater case in position in the vehicle. Attach the air ducts

Refrigerant lines and coolant hoses. Connect the electrical leads

Reposition the instrument panel into the vehicle and connect the electrical multi-plugs. Be sure the instrument panel is properly positioned and install all retaining bolts

Ventilation control head, the radio and the glove box assembly

A pillar trim and the kick panel trim plates

Lower instrument panel trim pieces

Steering column trim and the steering wheel

Center console and the shift lever cover. Install the shifter knob or handle

Refill the cooling system.

Evacuate, charge and leak test the air conditioning system.

Connect the negative battery cable.

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

5 & 7 Series

2001-03 5 Series And 2001 7 Series

Disconnect the negative battery cable.

Drain the cooling system into a clean container for reuse.

Remove or disconnect the following:

Screws retaining the center console

Ashtray assembly

Glove box door assembly

Right side heater case cover screws and remove the cover

Front vent drive motor

Plug from the inside temperature sensor

Heater core cover retaining screws

Cover clips and straps

Cover and gasket

Coolant hoses from the heater core

Heater pipe-to-heater core retaining bolts

Heater pipes

Heater core retaining bolts

Heater core by tilting it to the side

Fig. View of the heater/blower housing assembly

Fig. Removing the heater core cover

Fig. Removing the heater water pipes

Fig. Remove the heater by pulling to the right

To install:

Install or connect the following:

Heater core in the heater case

Heater core retaining bolts

Heater pipes to the heater core. Tighten the M6 bolts to 72-84 inch lbs. (8.1-9.5 Nm) and the M8 bolts to 16-17 ft. lbs. (21.7-23.0 Nm). Connect the heater hoses. Always use new O-rings on the heater pipes.

Heater case cover and retaining clips

Cover retaining screws. Make sure the cover gasket is properly positioned.

Front vent drive motor

Right heater case cover

Inside temperature sensor

Glove box door assembly

Center console and the ashtray

Refill the cooling system and connect the negative battery cable.

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

Except 2001-03 5 Series And 7 Series

Disconnect the negative battery cable.

Discharge and recover the air conditioning system refrigerant.

Drain the cooling system into a clean container for reuse.

Remove or disconnect the following:

Move the front seats completely back

Move steering column into the lower and extended position

Pillar trim

Instrument cluster

Headlight switch

On-board monitor assembly

Trim panel above the pedal assembly

Glovebox and instrument panel trim

Center speaker connection

Solar sensor connection

Fasteners securing the instrument panel

Instrument panel

Fig. Remove the center speaker connector (1), instrument panel fasteners (2, 3), then pull the instrument panel (4) back
A/C and coolant lines from the heater case

Fasteners securing the heater case

Heater case assembly

Heater core cover from the case

Coolant pipe retainers and pipes from the core

Fig. Remove retainers (1) and coolant pipes (2) from the core (3)
Heater core

To install:

Install or connect the following:

Heater core in the heater case

Coolant pipes

Heater core cover

Heater case assembly and fasteners

A/C and coolant lines and fasteners

Instrument panel and fasteners

Solar sensor connection

Center speaker connection

Glovebox and instrument panel trim

Trim panel above the pedal assembly

On-board monitor assembly

Headlight switch

Instrument cluster

Pillar trim

Refill the cooling system and connect the negative battery cable.

Recharge the A/C system with refrigerant

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

5, 7 And 8-Series

Removal And Installation

Disconnect the negative battery cable.

Drain the cooling system into a clean container for reuse.

Remove or disconnect the following:

Screws retaining the center console. Remove the ashtray assembly

Glove box door assembly

Right side heater case cover screws and remove the cover

Front vent drive motor. Disconnect the plug from the inside temperature sensor

Heater core cover retaining screws. Remove the cover clips and straps

Cover and gasket. Disconnect the coolant hoses from the heater core

Heater pipe-to-heater core retaining bolts. Remove the heater pipes

Heater core retaining bolts. Remove the heater core by tilting it to the side

Fig. View of the heater/blower housing assembly- 5, 7 and 8-Series

Fig. Removing the heater core cover- 5, 7 and 8-Series

Fig. Removing the heater water pipes- 5, 7 and 8-Series

Fig. Remove the heater by pulling to the right-5, 7 and 8-Series

To install:

Install or connect the following:

Heater core in the heater case. Install the heater core retaining bolts

Heater pipes to the heater core. Tighten the M6 bolts to 72-84 inch lbs. (8.1-9.5 Nm) and the M8 bolts to 16-17 ft. lbs. (21.7-23.0 Nm). Connect the heater hoses. Always use new O-rings on the heater pipes.

Heater case cover and retaining clips. Install the cover retaining screws. Make sure the cover gasket is properly positioned

Front vent drive motor. Install the right heater case cover

Inside temperature sensor. Install the glove box door assembly

Center console and the ashtray

Refill the cooling system and connect the negative battery cable.

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

5- & 7-Series

2001-03 5 Series & 2001 7 Series

Disconnect the negative battery cable.

Drain the cooling system into a clean container for reuse.

Remove or disconnect the following:

Screws retaining the center console

Ashtray assembly

Glove box door assembly

Right side heater case cover screws and remove the cover

Front vent drive motor

Plug from the inside temperature sensor

Heater core cover retaining screws

Cover clips and straps

Cover and gasket

Coolant hoses from the heater core

Heater pipe-to-heater core retaining bolts

Heater pipes

Heater core retaining bolts

Heater core by tilting it to the side

Fig. View of the heater/blower housing assembly

Fig. Removing the heater core cover

Fig. Removing the heater water pipes

Fig. Remove the heater by pulling to the right

To install:

Install or connect the following:

Heater core in the heater case

Heater core retaining bolts

Heater pipes to the heater core. Tighten the M6 bolts to 72-84 inch lbs. (8.1-9.5 Nm) and the M8 bolts to 16-17 ft. lbs. (21.7-23.0 Nm). Connect the heater hoses. Always use new O-rings on the heater pipes.

Heater case cover and retaining clips

Cover retaining screws. Make sure the cover gasket is properly positioned.

Front vent drive motor

Right heater case cover

Inside temperature sensor

Glove box door assembly

Center console and the ashtray

Refill the cooling system and connect the negative battery cable.

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

Except 2001-03 5 Series & 2001 7 Series

Disconnect the negative battery cable.

Discharge and recover the air conditioning system refrigerant.

Drain the cooling system into a clean container for reuse.

Remove or disconnect the following:

Move the front seats completely back

Move steering column into the lower and extended position

Pillar trim

Instrument cluster

Headlight switch

On-board monitor assembly

Trim panel above the pedal assembly

Glovebox and instrument panel trim

Center speaker connection

Solar sensor connection

Fasteners securing the instrument panel

Instrument panel

Fig. Remove the center speaker connector (1), instrument panel fasteners (2, 3), then pull the instrument panel (4) back

A/C and coolant lines from the heater case

Fasteners securing the heater case

Heater case assembly

Heater core cover from the case

Coolant pipe retainers and pipes from the core

Fig. Remove retainers (1) and coolant pipes (2) from the core (3)

Heater core

To install:

Install or connect the following:

Heater core in the heater case

Coolant pipes

Heater core cover

Heater case assembly and fasteners

A/C and coolant lines and fasteners

Instrument panel and fasteners

Solar sensor connection

Center speaker connection

Glovebox and instrument panel trim

Trim panel above the pedal assembly

On-board monitor assembly

Headlight switch

Instrument cluster

Pillar trim

Refill the cooling system and connect the negative battery cable.

Recharge the A/C system with refrigerant

Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

E30 Models

Disconnect the negative battery terminal. Remove the center console and the driver's side instrument panel trim next to the steering column. Drain the coolant.

Loosen the coolant pipe clamp near the heater connection.

Remove the duct from the heater to the rear heating duct.

Place some rags or a small container under the heater connection to catch any spilled coolant. Remove the bolts from the heater connection and separate the joint.

Remove the heater core bolts and remove from the heater housing.

To install:

Replace the heater core into the heater housing and replace the bolts. Replace the O-rings on the heater pipe joint. Connect the pipe to the heater core and install the bolts.

Install the rear heating duct connection and the pipe holding clamp. Install the instrument panel trim and the center console. Fill the cooling system and bleed. Connect the negative battery terminal.

E36 3 Models

Fig. Remove the nut to disconnect the water flange-E36 3 Series

Fig. Remove the nut and the O-rings from the flange-E36 3 Series

Fig. Remove the trim screws before disconnecting the lower trim-E36 3 Series

Fig. Remove the bolt to disconnect the flange at the heater core-E36 3 Series

Fig. Remove the screw to withdraw the heater core-E36 3 Series

Turn the ignition switch to the OFF position. Remove the air intake cowl weather-stripping. Remove the grille by gently prying out.

Remove the 2 screws inside the air intake cowl holding the electrical duct.

Remove the 2 screws holding the right side of the air intake cowl and remove the screw holding the left side. Pull the cowl out from above. It may be very hard to remove, but it will come out.

Remove the nut from the heater connection and pull off the connection. Blow air into the intake hose to force the coolant out of the heater core. This will prevent coolant from dripping onto the carpeting.