Engine Cooling - 3.0l v6 - Avk Audi A6 C5 рестайлинг

Cooling system components, removing and installing

Note. The cooling system is under pressure when the engine is warm. If necessary reduce pressure before repair. Secure all hose connections using hose clamps appropriate for the model type: see Parts catalog VAG1921 hose clip pliers are recommended for installing spring-type clamps. Always replace gaskets, seals and O-rings. The arrows which are marked on coolant lines and hoses must face each other.

Coolant hose connection diagram

The following list pertains to (Scheme 52).

1. Radiator Removing-and installing, see «RADIATOR, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) After replacing, replace coolant
2. Bleeder screw, 15 Nm
3. Coolant thermostat Removing and installing, see «COOLANT REGULATOR, REMOVING, INSTALLING AND CHECKING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk__coolant-regulator-removing-installing-and-checking) Checking, see «TIGHTENING TORQUE»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk)
4. Cylinder head/Cylinder block After replacing, replace coolant
5. Throttle valve control module -J338
6. Bleeder hole at coolant hose to heater core
7. Heater core After replacing, replace coolant
8. Expansion tank with cap See «PRESSURE RELIEF VALVE IN CAP, CHECKING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk__pressure-relief-valve-in-cap-checking)
9. Oil cooler
10. Coolant pump Removing-and installing, see «COOLANT PUMP, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) Check for ease of movement

Special Tools and Equipment

1. VAG1274/8
2. VAG1274/10 adapter for VAG1274 tester
3. VAG1306 drip tray for VAG1202A
4. VAG1921 hose clip pliers
5. T10007 refractometer

Draining

Note. Drained coolant must be stored in a clean container for disposal or reuse.

1. Open cap of coolant expansion tank.
2. For vehicles with auxiliary heater, remove bolts (arrows) for exhaust pipe of parking heater/auxiliary heater at noise insulation.
3. Loosen mounting parts -1 to 4- and remove noise insulation.
4. Place VAG1306 Drip Tray beneath engine.
5. Turn radiator drain plug (at bottom of radiator) counterclockwise (arrow), if needed attach accessory hose to connection flange and drain coolant.
6. In addition, disconnect coolant hose at oil cooler (arrow) and drain remaining coolant.

Filling

Note. The cooling system must be filled year round with a mixture of water and frost and corrosion protection additives. Only use coolant additive G 012 A8 D (according to TL VW 774 D) Characteristic: red color

1. If the fluid in expansion tank is brown, G012 A8 D has been mixed with other coolant. In this case, flush cooling system and change coolant. To flush, fill cooling system with clear water and let engine run for approx. 2 minutes. Flushing system should remove most of old coolant.
2. G 012 A8 D and coolant additives are marked with "according to TL VW 774 D" prevent frost and corrosion damage as well as lime deposits. They also raise the boiling point. Therefore, cooling system must be filled year round with frost and corrosion protection additives.
3. A higher boiling point improves engine reliability under heavy load particularly in countries with tropical climates.
4. Frost protection must be ensured to about -25° C (about -35 ° C in countries with arctic climates).
5. The coolant concentration must not be reduced by adding water even in warmer seasons and in warmer countries. The coolant additive portion must be at least 40%.
6. If for climatic reasons greater frost protection is required, the amount of G 012 A8 D can be increased, but only up to 60% (frost protection to about -40 ° C), otherwise frost protection and cooling effectiveness will be reduced again.
7. Use only clean drinking water for mixing with the coolant.
8. If the radiator, heater core, cylinder head or cylinder head gasket is replaced, completely replace the engine coolant.
9. For coolant G012 A8 D, use T10007 refractometer to test frost protection in cooling system.

Recommended mixture ratios

RECOMMENDED MIXTURE RATIOS OF WATER AND COOLANT

Scheme 52

1. Unscrew drain plug (arrow) at radiator clockwise.
2. Connect coolant hose to oil cooler (arrow).
3. Screw VAG1274/8 adapter onto expansion tank.
4. Attach VAG1274/10 Special Tool to VAG1274/1 Adapter.
5. Pull off rubber seal of plenum chamber cover in direction of arrow.
6. Remove plenum chamber cover -1- toward front.
7. Remove front engine cover (arrow)
8. Remove bleeder screw (arrow).
9. Fill up coolant until it escapes from the coolant hose bleeder hole.
10. Tighten bleeder screw to 15 Nm.

Note. Always replace sealing ring.

1. Slide back boot for coolant hoses at connection of heater core.
2. Loosen coolant hose to heater core and pull back hose sufficiently so that bleeder hole in coolant hose (arrow) is no longer sealed by connection.
3. Fill up coolant until it escapes from coolant hose bleeder hole.
4. Slide coolant hose onto connection sleeve and secure using spring-type clamp.
5. Install coolant expansion tank cap.
6. Start engine and maintain an engine speed of about 2000 RPM for approx. 3 minutes.
7. Allow engine to idle until lower coolant hose at radiator is hot.

1. Check coolant level and top off if necessary. With engine at operating temperature, coolant level must be at max. marking, with engine cold, it must be between min. and max. marking.
2. Turn engine off.

Tightening torque

TIGHTENING TORQUE: BLEEDER SCREW AT COOLANT PIPE

Coolant pump and coolant regulator

The following list pertains to see scheme 14.

1. 10 Nm
2. 10 Nm
3. Coolant pump Removing- and installing, see «COOLANT PUMP, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) Check for ease of movement
4. Gasket Always replace
5. O-ring Always replace
6. Coolant thermostat with connecting piece Can only be replaced together with the coolant regulator Removing and installing, see «COOLANT REGULATOR, REMOVING, INSTALLING AND CHECKING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk__coolant-regulator-removing-installing-and-checking) Checking, see «TIGHTENING TORQUE»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk)
7. 10 Nm

Scheme 53

1. Drain coolant. See «COOLANT, DRAINING AND REFILLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) .
2. Remove toothed belt. See «TOOTHED BELT, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .
3. Remove camshaft gears from right cylinder head.
4. Unscrew bolts -1- and remove bracket with idler roller.
5. Unscrew bolts -2- and remove toothed belt guard ar rear right.
6. Remove eccentric pulley for toothed belt.
7. Remove nuts -2- for toothed belt guard ar left rear.
8. Remove bolts -1- for coolant pump and remove coolant pump.

Installing

Installation is reverse of removal, noting the following

Note. Replace gaskets and O-rings.

1. Install toothed belt (adjust timing). See «INSTALLING (ADJUSTING VALVE TIMING)»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk__installing-adjusting-valve-timing) .
2. Top off coolant. See «FILLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk__filling) .

Tightening torques

TIGHTENING TORQUES: TOOTHED BELT AND COOLANT PUMP

Coolant regulator, removing, installing and checking

Note. Coolant regulator is another term for coolant thermostat.

Scheme 54

1. Drain coolant. See «COOLANT, DRAINING AND REFILLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) .
2. Remove intake manifold. See «REMOVING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .
3. Remove bolts -1- and -2-.
4. Disconnect coolant hose (arrows).
5. Remove coolant regulator (thermostat) with connection.

Installation is reverse of removal, noting the following

Note. Replace O-ring.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Install coolant regulator with coolant regulator housing.
3. Install intake manifold. See «INSTALLING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .

IGHTENING TORQUE: COOLANT REGULATOR (THERMOSTAT) HOUSING

Check coolant regulator

1. Warm thermostat in hot water bath.

THERMOSTAT VALVE OPENING TEMPERATURE

Coolant pipes, overview

The following list pertains to see scheme 18.

1. 10 Nm
2. Front coolant pipe Removing and installing, see «FRONT COOLANT PIPE, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk)
3. 22 Nm
4. O-rings Always replace
5. Coolant pipe, right Removing and installing, see «RIGHT COOLANT PIPE, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk)
6. 10 Nm
7. O-ring Always replace
8. 10 Nm
9. O-ring Always replace
10. Engine Coolant Temperature (ECT) sensor -G2-/-G62
11. Retaining clip
12. Coolant hose to heater core
13. Coolant hose to expansion tank
14. Connecting piece Tighten to 15 Nm
15. Seal Always replace
16. Coolant hose to heater core
17. 10 Nm
18. Rear coolant pipe Removing and installing, see «REAR COOLANT PIPE, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk)
19. O-rings Always replace
20. Coolant hose To top of radiator
21. Coolant hose to oil cooler

1. 3094 hose clamps
2. Oil receptacle

Removing

Note. All cable ties opened or cut during engine removal must be reinstalled at the same locations during installation.

1. Remove intake manifold. See «REMOVING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .
2. Toothed belt, removing. See «REMOVING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .
3. Remove camshaft gears from left cylinder head.
4. Unscrew bolts-1- and -2- and remove toothed belt guard at rear left.
5. Place oil pan underneath.
6. Clamp off both hoses at hydraulic fluid supply line using 3094 hose clamps.
7. Disconnect both hydraulic hoses from supply line.
8. Disconnect coolant hoses at front coolant pipe.
9. Remove bolts -1- and -2- and move lines at coolant pipe to side.
10. Remove coolant pipe toward front (arrow).

Installation is reverse of removal, noting the following

Note. Secure all hose connections using hose clamps appropriate for the model type: see Parts catalog Replace O-rings.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Coat new O-ring with G12 and slide onto coolant pipe.
3. Slide front coolant pipe into the hole at rear coolant pipe.
4. Install intake manifold. See «INSTALLING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .
5. Install toothed belt (adjust timing). See «INSTALLING (ADJUSTING VALVE TIMING)»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk__installing-adjusting-valve-timing) .
6. Fill up power steering fluid and bleed steering system

See POWER STEERING FLUID LEVEL, CHECKING; STEERING SYSTEM, BLEEDING AND CHECKING FOR LEAKS

IGHTENING TORQUES: COOLANT PIPE AND TOOTHED BELT GUARD

1. Remove intake manifold. See «REMOVING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .
2. Disconnect rear coolant hose -2- from right coolant pipe.
3. Remove bolt -1-.
4. Pull right coolant pipe out of cylinder block toward rear (arrow).
5. Remove catalytic converter upward.

Installation is reverse of removal, noting the following

Note. Secure all hose connections using hose clamps appropriate for the model type: => Parts catalog Replace O-rings.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Coat new O-ring with G12 and slide onto coolant pipe.
3. Slide coolant pipe into the hole at cylinder block.
4. Install intake manifold. See «INSTALLING»(/audi/a6/c5-2001-2004/remont/mechanical/#30l-v6-engine-code-avk) .

TIGHTENING TORQUES: RIGHT COOLANT PIPE

Note. All cable ties opened or cut during engine removal must be reinstalled at the same locations during installation.

1. Remove right coolant pipe. See «RIGHT COOLANT PIPE, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) .
2. Expose wires at hose of crankshaft housing ventilation.
3. Remove hose of crankshaft housing ventilation (arrows).

Vehicles with automatic transmission

1. Disconnect vacuum hose to brake booster (arrows).

All

1. Remove heat shield for harness connectors at left of bulkhead.
2. Remove coolant hose -4-.
3. Remove bolts -2- and nut -5- and remove hose for secondary air injection.
4. Disconnect vacuum hose -3- from combination valve.
5. Remove bolts -1- and remove combination valve for secondary air injection.
6. Remove coolant hose -6-.

Note. Illustration is shown with engine removed.

Scheme 55

1. Disconnect electrical harness connector -2- at Engine Coolant Temperature (ECT) Sensor -G2-/-G62-.
2. Disconnect hydraulic line of power steering at rear coolant pipe -1-.
3. Remove screw clips for electrical wiring harness at rear coolant pipe.
4. Expose electrical wires at rear coolant pipe.
5. Remove bolts -1- and -2-.
6. Remove rear coolant pipe toward rear.

Installation is reverse of removal, noting the following

Note. Secure all hose connections using hose clamps appropriate for the model type: see Parts catalog Replace seals and O-rings.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Coat new O-rings with G12 and slide onto coolant pipe.
3. Install right coolant pipe. See «RIGHT COOLANT PIPE, REMOVING AND INSTALLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk) .

TIGHTENING TORQUES: REAR COOLANT PIPE AND POWER STEERING PRESSURE LINE

1. VAG1306 drip tray for VAG1202A

1. Remove front bumper

See FRONT BUMPER .

Note. Drained coolant must be stored in a clean container for disposal or reuse.

1. Open cap of coolant expansion tank.
2. For vehicles with auxiliary heater, remove bolts (arrows) for exhaust pipe of parking heater/auxiliary heater at noise insulation.
3. Loosen mounting parts -1 to 4- and remove noise insulation.
4. Place VAG1306 Drip Tray beneath engine.
5. Turn radiator drain plug -2- counterclockwise, if needed attach accessory hose to connection flange and drain coolant.
6. Pull off retaining clip -1- for lower coolant hose and disconnect coolant hose from radiator.
7. Disconnect left coolant hose from radiator (arrow).
8. Remove cover -1- in engine compartment (left side).
9. Disconnect top coolant hose from radiator (arrow).

1. Remove cover -1- in engine compartment (right side).
2. Remove bolts (arrows).
3. Remove air guide -1-.

Note. Observe the rules of cleanliness for working on automatic transmissions

1. Place an oil receptacle underneath.
2. Disconnect top (arrow) and bottom ATF lines from radiator
3. Tie up ATF lines to top of long member to prevent fluid from escaping.

1. Remove air guides from left and right of radiator (arrows).
2. Unclip temperature sensor -2- for outside temperature display from bracket.
3. Remove bolts -1- and -4- and remove power steering cooling coil, hoses remain connected.
4. Disconnect harness connector -3- at High Pressure Sensor -G65-.

1. Remove condenser mounting bolts (arrows).

Note. To prevent damage to the condenser as well as to the coolant lines/hoses, make sure the lines and hoses are not over-stretched, kinked or bent.

1. Carefully swing condenser downward and move aside.
2. Unlock both radiator retaining bolts and remove by pulling upward (arrows).
3. Tilt radiator forward, pull up and remove.

Installation is reverse of removal, noting the following

1. Install front bumper See «FRONT BUMPER»(/audi/a6/c5-2001-2004/remont/exterior-body-panels/#bumper) .
2. Top off coolant. See «FILLING»(/audi/a6/c5-2001-2004/remont/cooling-fan/#engine-cooling-30l-v6-avk__filling) .

Note. Complete coolant must be replaced if the radiator was replaced.

1. Secure ATF line.
2. Check ATF level

See SERVICING - A/T (01J, CVT) or CHECKING FLUID LEVELS .

TIGHTENING TORQUE: CONDENSER

1. VAS1978 wiring harness repair kit

Note. Coolant FC (Fan Control) Control Module and coolant fan motor are supplied as a replacement part without harness connector. Repairs to wiring harnesses and connectors must only be performed using the VAS1978 wiring harness repair kit.

Detailed instructions on how to use VAS1978 are supplied in the enclosed operating instructions.

The manual also explains how to repair open circuits and faulty connectors.

Scheme 56

1. VAG1274 cooling system tester
2. VAG1274/8
3. VAG1274/9 adapter

Test requirement

1. Engine at operating temperature.

Test sequence

1. Open cap of coolant expansion tank.
2. Attach VAG1274 Cooling System Tester together with VAG1274/8 adapter to coolant expansion tank.
3. Use tester hand pump to create a pressure of approx. 1.0 bar.
4. If pressure drops, detect leak and repair malfunction.

Pressure relief valve in cap, checking

1. Attach VAG1274 cooling system tester together with VAG1274/9 adapter to cap.
2. Pump using hand pump. Pressure release valve must open at a positive pressure of 1.4 to 1.6 bar.

See also:
• TOOTHED BELT, REMOVING AND INSTALLING
• INSTALLING (ADJUSTING VALVE TIMING)
• POWER STEERING FLUID LEVEL, CHECKING; STEERING SYSTEM, BLEEDING AND CHECKING FOR LEAKS
• FRONT BUMPER
• SERVICING - A/T (01J, CVT)
• RADIATOR, REMOVING AND INSTALLING
• COOLANT REGULATOR, REMOVING, INSTALLING AND CHECKING
• PRESSURE RELIEF VALVE IN CAP, CHECKING
• FILLING