Removing the block head for 4- and 5-cylinder engines
Remove the negative battery cable.
Engine with Mono-Motronic injection system: remove the air filter.
5-cylinder engine: remove the viscous fan and V-ribbed belt Remove the upper front cross member of the engine compartment, unscrew the fan on the right, tilt it forward and support it.
Drain coolant, loosen coolant hoses at cylinder head.
Remove the ignition distributor cap together with the high voltage wires (5 cylinder engine) (see ch. «Ignition system»).
Disconnect the throttle cable.
Mark and disconnect all electrical wires near the cylinder head and the injection unit or intake manifold.
Separate the fuel supply pipes of the injection system at the couplings.
Mark and remove the vacuum hoses on the intake manifold or on the throttle body, as well as the vacuum hoses from the brake booster.
When working with a 5-cylinder engine, remove the upper part of the exhaust pipe (chapter «Injection system KE-III-Jetronic and KE-Motronic»). Also remove the injection nozzles, leaving the high pressure fuel lines connected.
Remove the wire lugs from the starting fuel valve, unscrew the valve and set aside with the fuel line connected.
Mark and remove injection plugs. Helps with installation: plugs have different colors
4-cylinder engine with KE-Motronic injection system and 5-cylinder engine: remove the fuel mixture adjuster together with the air filter housing.
Disconnect the exhaust pipe from the exhaust manifold.
Unscrew the upper mounting of the alternator on the 4-cylinder engine. Before doing this, loosen the V-belt.
Remove the toothed belt guard, loosen the toothed belt and remove from the camshaft gear.
Remove the cylinder head cover.
Loosen the cylinder head bolts in reverse order as shown in the illustrations on the next page above. Before this, the engine must be cool, because the warm cylinder head can be deformed after removal.
Remove the cylinder head together with the intake and exhaust manifolds, as well as the ignition distributor (5 cylinder engine). If it does not come off without effort, help yourself with light blows with a plastic hammer.
Removing the block head from a 6-cylinder engine
The description of the work refers to the cool cylinder head. Removal of the right head of the block of cylinders happens in the same way.
Remove engine guard and V-belt cover.
Remove V-belt and toothed belt.
Disconnect the exhaust pipe from the exhaust manifold, drain the coolant.
Disconnect the air duct from the exhaust manifold and disconnect the plug of the Hall sender.
Disconnect crankcase breather hoses at left cylinder head and right cylinder head.
Disconnect the air intake hose from the air filter.
Disconnect the air conditioning and/or differential lock vacuum tube from the throttle body on the left.
Press air duct downwards and remove together with crankcase breather hoses.
Detach cable guard «gas», hang out and release the drive cable «gas». Disconnect the plug connection of the intake air temperature sensor and the idle speed control valve.
Separate the fuel drain and filler lines.
The cylinder head bolts must be tightened in the numbered sequence. Depicted (from left to right) 4-, 5- and 6-cylinder engines. The arrows indicate the direction of movement.
Unscrew and remove the exhaust manifold.
Close the holes with a clean cloth.
Unscrew the coolant pipe at the rear of the cylinder head.
Remove the carbon monoxide intake tube.
Remove lambda probe.
Detach the exhaust manifold insulation sheet.
Remove the cylinder head cover.
Remove the rear part of the toothed belt guard.
Disconnect the pipes from the coolant reservoir to the pump on the cylinder head.
Loosen the cylinder head bolts in reverse order as shown in the illustrations above. The engine must be cold.
Remove the cylinder head. If it does not come off without effort, help with light blows with a plastic hammer.
Remove the old cylinder head gasket. The sealing surfaces on the cylinder head and cylinder block must be absolutely clean, free of any gasket residue. Do not scratch the soft sealing surface of the cylinder head with a hard tool.
Check the cylinder head for deformation (important when overheating).
Checking the removed cylinder head. All types of engines
Place a long metal ruler or a guaranteed straight metal angle along the cleaned sealing surface of the cylinder head.
Check with a feeler gauge whether there is a deflection greater than 0.1 mm at any point. In the latter case, the cylinder head will need to be ground before installation.
A minimum height must be observed - measured from top to bottom sealing surface - 132.6 mm for 4-cylinder engines and 132.75 mm for 5- and 6-cylinder engines.
If you are installing a new cylinder head, lightly lubricate the hydraulic tappet guides with oil. Lubricate with oil and install the camshaft as previously described.
If necessary, install the screw cap on the replacement cylinder head of the 6-cylinder engine.
The threads on the cylinder head bolts and in the corresponding holes on the cylinder block must be clean and undamaged, otherwise the tightening torque will not match when tightening the bolts.
Installation. All types of engines
There must be no oil or water in the cylinder block bolt holes.
Rotate the crankshaft back a little against the direction of rotation so that no piston is at TDC, otherwise the open valve may collide with such a piston when the cylinder head is put on.
Lay the cylinder head gasket on the cylinder block so that the part number or designation «Oben» («up») pointed to the cylinder head.
Fit the cylinder head. For this purpose, two guide bolts are used in the workshop when working with 4- and 5-cylinder engines.
You can make this tool yourself from two old cylinder head bolts: saw off the bolt head and saw through the slot at the top.
After installing a few bolts, you can remove the guide bolts.
Install the cylinder head bolts and tighten in the sequence shown above:
The bolts are thus finally tightened and must not be tightened again under any circumstances.
Pay attention to the adjustment of the cable drive when assembling «gas» and installation of injection nozzles for a 5-cylinder engine (injection chapter).
Important: pay attention to the tightening sequence when installing the exhaust manifold on a 6-cylinder engine.
In addition, on 4- and 5-cylinder engines, check the ignition setting (chapter «Ignition system»).
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