Removal and installation, disassembly and assembly of the cylinder head (Nissan Micra K12)

Removal and installation

Cylinder head fasteners

1. Release the pressure in the fuel system (see section Relieving pressure in the fuel system).

2. Drain the cooling system (see section Replacing the coolant).

3. Remove the following components:

• Right front wheel arch liner;
• Generator and compressor drive belt K/V (see section Replacement of auxiliary drive belts and intermediate belt rollers);
• Air duct and air cleaner cover assembly (see section Removal and installation air intake tract components);
• Inlet manifold (see section Removal and installation the intake manifold);
• Assembly of the fuel distribution line with injectors (see section Removal and installation of fuel injectors and fuel distribution line);
• Upper and lower radiator hoses (see Chapter Engine cooling, heating, ventilation and air conditioning systems);
• Generator and its bracket (see Chapter Engine electrical systems);
• Exhaust manifold with catalytic converter (see section Removal and installation the exhaust manifold, catalytic converter and lambda probe);
• Ignition coils (see section Replacing spark plugs);
• Cylinder head cover (see section Removal and installation the cylinder head cover);
• Camshafts (see section Removal, inspection and installation of camshafts);
• Lambda probe wiring bracket (see illustration Exhaust Manifold and Catalytic Converter Mounting Components);
• Outlet pipe (thermostat cover), thermostat, ECT sensor, heater hose and cooling system intake pipe (see Chapter Engine cooling, heating, ventilation and air conditioning systems).

4. Remove the cylinder head mounting bolts in the following sequence:, reverse shown in the illustration.



5. Remove the cylinder head gasket.



6. Measure the thread diameter of the cylinder head bolts at the locations shown in the illustration and subtract the smaller value from the larger one. If the result exceeds 0.12 mm, replace the bolt.

If the minimum diameter d2 is not minimum, use the minimum diameter instead of d2.



7. Apply sealant evenly to the areas shown in the illustration and install new cylinder head gasket.



8. Install the cylinder head and tighten its mounting bolts in the sequence shown in the illustration and in the sequence specified in Specifications.



Pre-lubricate the threads and the lower edges of the bolt heads with engine oil. When loosening the bolts in the second stage, unscrew them in the reverse order. Auxiliary bolts (Nos. 11-13) should be tightened only after the main bolts have been fully tightened.

9. Further installation is carried out in the reverse order of dismantling the components.

Disassembly and assembly

Since disassembly and assembly of the cylinder head are typical procedures for all vehicles, only illustrations are provided to explain the assembly of the cylinder head and some features.

Cylinder Head Assembly Components

1. When installing the valve stem seal, observe the dimensions shown in the illustration.





2. When installing the spark plug bushing, clean the mating surfaces from old sealant and apply sealant to the area shown in the illustration. The height (H) of the bushing protrusion should be 41÷42 mm.

3. After disassembling the cylinder head, check its parameters and the parameters of the valve mechanisms, using the following Specifications. If necessary, replace defective valve seats and guides, the valves themselves, or the cylinder head assembly with the upper camshaft bearings. A deformed cylinder head cannot be resurfaced.