Heat exchanger, installing: Installing

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With heater core removed, check for contamination of air conditioner (by way of heater core duct).
Remove any dirt or remnants of escaped coolant from air conditioner (e.g. after removing leaking heater core).

Fig 1: Checking Seals Installed To Heater Core

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Check seals - A -, - B - and - C - installed to heater core. Only fit heater core with intact seals.

Fig 2: Identifying New Seals & Heater Core

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Moisten new seals - A - slightly with coolant.
Insert new seals - A - (included in scope of delivery of heater core) in connections of heater core - B -.
Slide heater core - C - into air conditioner.

Fig 3: Identifying Old/New Clips, Coolant Lines & Heater Core

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Remove old clips - A - from both coolant lines - B - and - C -.
Install new clips - A - (included in scope of delivery of heater core) to both heater core coolant lines as shown.
Press both coolant lines - B - and - C - into connections of heater core - D -.
Re-check position of seals between coolant lines and heater core.

Fig 4: Identifying Clips, Coolant Lines & Heater Core

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Install the two coolant lines - B - and - C - with clips - A - to the heater core.
Check position of both clips - A -. They must completely surround the flange at the heater core and coolant line and not make contact with other components.
Tighten bolts at clips - A - to 2.5 Nm.
Make sure coolant hoses are properly connected to heater core. observe markings:

A - Supply hose from cylinder head

B - Return hose to water pump

Reinstall components removed (with the exception of drivers storage compartment) in reverse order.
Bleed coolant circuit →
- 19 - ENGINE - COOLING SYSTEM for 1.8 LITER 4-CYL. 5V TURBO ENGINE MECHANICAL, ENGINE CODE(S): AMB
- 19 - ENGINE - COOLING SYSTEM for 2.0 LITER 4-CYL. 4V TURBO ENGINE MECHANICAL, ENGINE CODE(S): BPG, BWT
- 19 ENGINE - COOLING SYSTEM for 3.0 LITER 6-CYL. 5V ENGINE MECHANICAL, ENGINE CODE(S): AVK, BGN
- 19 - ENGINE - COOLING SYSTEM for 3.2 V6 4V ENGINE MECHANICAL, ENGINE CODE(S): BKH
- 19 - ENGINE - COOLING SYSTEM for 4.2 LITER V8 4V ENGINE MECHANICAL, ENGINE CODE(S): BNS
- 19 - ENGINE - COOLING SYSTEM for 4.2 LITER V8 5V ENGINE MECHANICAL, ENGINE CODE(S): BHF
.

NOTE:

The arrangement of the coolant lines to the heater core of the air conditioner is such that the heater core must also be bled. Proceed as follows:
- Bleed coolant circuit.
- Switch off ignition.
- Carefully open cap at coolant reservoir (observe safety precautions for opening cap) →
- 19 - ENGINE - COOLING SYSTEM for 1.8 LITER 4-CYL. 5V TURBO ENGINE MECHANICAL, ENGINE CODE(S): AMB
- 19 - ENGINE - COOLING SYSTEM for 2.0 LITER 4-CYL. 4V TURBO ENGINE MECHANICAL, ENGINE CODE(S): BPG, BWT
- 19 ENGINE - COOLING SYSTEM for 3.0 LITER 6-CYL. 5V ENGINE MECHANICAL, ENGINE CODE(S): AVK, BGN
- 19 - ENGINE - COOLING SYSTEM for 3.2 V6 4V ENGINE MECHANICAL, ENGINE CODE(S): BKH
- 19 - ENGINE - COOLING SYSTEM for 4.2 LITER V8 4V ENGINE MECHANICAL, ENGINE CODE(S): BNS
- 19 - ENGINE - COOLING SYSTEM for 4.2 LITER V8 5V ENGINE MECHANICAL, ENGINE CODE(S): BHF
.

Fig 5: Identifying Coolant Hoses

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Loosen clip at coolant hose - B -.
Slide back hose - B - until hole in hose is no longer sealed off by line.
Use cooling system tester V.A.G 1274/hand pump for example to increase pressure in coolant circuit.
Bleed heater core by way of hose - B - until there are no bubbles in coolant emerging.
Install coolant hose - B - and secure with clip.
Replenish coolant if necessary.

Fig 6: Identifying Clips, Coolant Lines & Heater Core

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Check coolant circuit for leaks, paying particular attention to connection between coolant lines and heater core. →
- 19 - ENGINE - COOLING SYSTEM for 1.8 LITER 4-CYL. 5V TURBO ENGINE MECHANICAL, ENGINE CODE(S): AMB
- 19 - ENGINE - COOLING SYSTEM for 2.0 LITER 4-CYL. 4V TURBO ENGINE MECHANICAL, ENGINE CODE(S): BPG, BWT
- 19 ENGINE - COOLING SYSTEM for 3.0 LITER 6-CYL. 5V ENGINE MECHANICAL, ENGINE CODE(S): AVK, BGN
- 19 - ENGINE - COOLING SYSTEM for 3.2 V6 4V ENGINE MECHANICAL, ENGINE CODE(S): BKH
- 19 - ENGINE - COOLING SYSTEM for 4.2 LITER V8 4V ENGINE MECHANICAL, ENGINE CODE(S): BNS
- 19 - ENGINE - COOLING SYSTEM for 4.2 LITER V8 5V ENGINE MECHANICAL, ENGINE CODE(S): BHF
Reinstall drivers storage compartment and remaining components removed.