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Removal and installation of the cylinder head / cylinder head gasket replacement
When removing the engine cylinder head to be cooled at least to room temperature. The exhaust and intake manifolds are connected. It describes the removal of engines VZ, B5, B6 and BP. At the end of the chapter are instructions for diesel engines. In distinction to the series E motors described in a separate chapter. See section Removing and installing the camshaft / variable valve timing. Faulty cylinder head is detected by one or more of the following characteristics: - Loss of power.
- Loss of coolant. White exhaust clouds on a warm engine.
- Loss of oil.
- The coolant in the engine oil, the oil level decreases and increases. Gray motor oil, foam marks on the dipstick, the oil is diluted.
- The engine oil in the coolant.
- Coolant strongly rages.
- No compression in two adjacent cylinders.
Withdrawal Engine V6 with injection system  | - Disconnect earth cable from the battery.
 | This data is erased from the memory of malfunctions of the engine or a protective code of a radio receiver. Before disconnecting the battery should read instructions in Section Removal and installation of the battery. |
- Injection engine: Release clamps and remove the intake hose.
- Petrol engine: Remove air filter, see chap. The power supply system, the carburettor, fuel injection system, Section Removal and installation of the air filter.
- If there is, remove the resonance chamber.
- Drain coolant, see. Chapter Introduction.
- Remove the drive gas, see. Chapter power supply system, the carburettor, fuel injection system, Section Check / removal and installation of automatic cold start.
- Automatic transmission: Detach the throttle cable.
- Turn off all electrical wires to the cylinder head. To facilitate the installation of the wire must first mark with tape.
- Unscrew earth cable -1- on the engine.
- Disconnect -2- lambda probe.
- Disconnect combo connector -3- on the ignition distributor.
- Disconnect combo connector -4- injection valves.
- Disconnect the combination sensor plug and the throttle controller -5- -6- idle.
- Disconnect terminal 4 -7 on the ignition coil.
- Disable combo connector -8 temperature switch of the cooling system.
- Disable the plug -9- coolant temperature sensor.
- Disconnect earth cable to the motor -10-.
- Disable combined carburetor -11- plugs connections.
- Disconnect the vacuum hose, after loosening the clamp.
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Injection engine Injection engine  | - Loosen hose clips and disconnect fuel hoses -2-. If you turn off the fuel to build around a rag to the weakening or spray fuel. Immediately close pipelines suitable stoppers, for example, clean bolts corresponding diameter. In order to facilitate subsequent installation of tape to mark fuel.
- If there is, turn off the vacuum hose -4- Tempostat.
- Disconnect vacuum hose vent -3.
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Carburetor engine Carburetor engine  Setting | - Before installing the scraper to clean the block and the cylinder head from sealing residues. At the same time the sealing surfaces must not be scratched. Ensure that the gasket remnants have not fallen into the cylinders. Cover the hole with a cloth.
- Check that the bolt holes in the cylinder head has not been oil, if necessary, remove the oil by compressed air. If compressed air is not, you can clear the opening with a small screwdriver wrapped with a cloth.
| In any case, the oil must be removed. |
 | - Check cylinder head for deformation of steel ruler and a feeler gauge.
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- Check deformation in these areas. The maximum permissible roughness of 0.15 mm. If the limit value is exceeded, the cylinder head must be treated (this is done in the studio).
- Check the cylinder head for cracks. If there is a crack, the head must be replaced.
- Check for water, oil and fuel hoses for cracks or breaks, if necessary, replaced.
- Check the valves and valve guides for wear and damage.
- Apply the cylinder head gasket with the holes in the cylinder block and the laying of the same.
- Coat a small amount of oil, and the contact surface of the cylinder head bolt threads.
 | - Tighten bolts to fit 10 to the cylinder head by hand. Then the bolts should be tightened in three passes. On each pass the bolts are tightened in the sequence of 1st to 10th.
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1st pass: 40 Nm 2nd pass: 60 Nm 3rd passage: 80 Nm
| Tighten the cylinder head bolts should be done very carefully. Before tightening, check the accuracy of the torque wrench. In addition, you must strictly follow the sequence of tightening. |
- Injection engine: Tighten the intake manifold with the efforts of 25 Nm and 45 Nm.
 | - Screw the front exhaust pipe to exhaust manifold with a force of 45 Nm.
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- Engine DOHC: Apply a shaded place sealant based on silicone (eg, DOW CORNING Q3-7057). Install a new valve cover gasket.
- Engine SOHC: Apply gasket into the groove in the cylinder head cover sealing compound based on silicone (eg, DOW CORNING Q3-7057). Apply a new cover gasket.
- Install the cylinder head cover and tighten with a force of 10 Nm.
- Install the timing belt. See Sections Removal and installation of a gear belt of engines VZ, B5, B6 (SOHC), BP (SOHC), Removing and installing toothed belt (DOHC).
- Install a bypass pipe cooling system and tighten the nut with a torque of 20 Nm.
 | - Connect all electrical wires and vacuum hoses in accordance with the put labels.
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- Wear heater hoses, and depending on the model or a snap to fix collars.
- Connect the supply and return fuel lines and secure the clamps.
- Set the air filter, see chap. The power supply system, the carburettor, fuel injection system, Section Removal and installation of the air filter.
- Check frost cooling liquid and pour it into the system. See Chapter Introduction.
- Connect the battery earth cable.
- If available, set the clock and set the security code radio.
- Change the engine oil, see. Chapter Introduction.
- Check the ignition timing if you want to adjust. See Chapter Ignition system, Section Checking / adjusting the moment of ignition.
- Check idle speed and adjust if necessary, see chap. The power supply system, the carburettor, the fuel injection system.
- Warm up the engine, check the coolant level and the tightness of all hose connections.
- If necessary, check valve clearance. See Section Checking / adjusting valve clearance.
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Diesel engine Withdrawal | - Remove the battery and unscrew the battery holder, see chap. Electrical system, Section Removing and installing the battery.
- Remove the air filter, see chap. The power supply system, the carburettor, fuel injection system, Section Removal and installation of the air filter.
- Remove the injection pipes, see. Chapter diesel engine.
- Unscrew the supply and return pipes.
 | - Hold camshaft wrench, for example, HAZET 279-15, unscrew the bolt gear camshaft. Remove the wheel of a cam, if necessary, to bring down the light blows of a rubber hammer.
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| While holding the camshaft not to damage the cylinder head with a wrench. |
- Unscrew the rear casing of a gear belt.
 | - Unscrew bolts -arrows- front engine mounts.
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 | - Loosen the cylinder head bolts in the sequence 1 to 10 for the first pass on 1/2 turns for the second pass one turn and a full turn on the third pass.
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| The weakening of the cylinder head bolts in an improper manner can lead to deformation or cracks in the cylinder head. |
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Setting | - Check cylinder head for distortion. The maximum allowable strain on the sealing surface of Noah may be 0.1 mm. If the deformation exceeds the limit value, the cylinder head must be treated (this is done in the studio).
- Measure the protrusion of the plug. Required value: 7 - 8 mm. If you want to score a hammer stopper to the specified size. Coat the new seal round section small amount of oil and insert it into the groove of the tube.
- Measure the length of the cylinder head bolts from the lower edge of the head to the end of the rod. The maximum length of 114.5 mm should not be exceeded. If the value does not meet the requirement, the bolt should be replaced.
 | - Install the 10 cylinder head bolts torque arms until they rest on the head. Then tighten the bolts in three passes. On each pass the bolts are tightened to that shown in sequence from the 1st to the 10th.
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1st pass: a torque wrench with a force of 30 Nm 2nd pass: tighten 1/4 turn hard key without removing the key 3rd passage: tighten 1/4 turn hard key without removing the key
- Screw the front engine mounting with a force of 45 Nm.
 | - Establish a back casing of a gear belt and screw with a force of 10 Nm.
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- Install gear and a wedge. To tighten the bolts to hold the camshaft key. Torque: 50 Nm.
- Install the timing belt, see. Chapter diesel engine.
- Install the fuel supply and return, as well as pipeline injection, see. Chapter diesel engine.
- Set the air filter, see chap. The power supply system, the carburettor, fuel injection system, Section Removal and installation of the air filter.
- Install the battery holder and screw with a force of 10 Nm.
- Install the battery, see chap. Electrical system, Section Removing and installing the battery.
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