H4M engine dismantling

We mount the engine on the stand for dismantling and assembling of units.

We unscrew the oil drain plug and drain the oil from the engine sump.

We slacken the water pump pulley mounting bolts, locking the water pump pulley with a screwdriver.

(If the drive belt is held, the pulley need not be locked.)

We unscrew the bolts with a 10 mm socket and remove the pulley.

We disconnect the heater hoses from the throttle body with pliers.

We disconnect the throttle body heater hoses from the coolant outlet pipe and remove the hoses from the engine.

We remove the crankcase ventilation pipe.

We remove the intake module complete with the throttle body and gaskets.

With an 8 mm socket we remove the wiring harness mounting bracket.

With 8 mm and 10 mm sockets we remove the fuel rail shield.

We disconnect the connectors from the ignition coils.

We disconnect the injector wiring connectors from the fuel injectors and remove the harness from the engine.

With an 8 mm socket we unscrew the ignition coil mounting bolts and remove the coils.

With a 14 mm spark plug wrench we unscrew the spark plugs.

With a 10 mm socket we unscrew the mounting bolt and remove the phase sensor.

With an 8 mm socket we unscrew the mounting bolt and remove the phase regulator solenoid valve.

With a grab tool we remove the oil level dipstick tube.

With an 8 mm socket we unscrew the bolts and remove the cylinder head cover.

We set the TDC of the compression stroke in the first cylinder. To do this:

We turn the crankshaft clockwise until mark 1 (Fig. 2) on the crankshaft pulley and mark 2 on the timing drive cover align.

At this, the marks of the camshaft phase regulator 1 and the intake camshaft sprocket 2 must be positioned as shown in the figure.

If this is not the case, we turn the crankshaft one more revolution until the mark on the crankshaft pulley and on the timing drive cover align.

We fit the flywheel locking tool 67.7820-9708 or 0000143100.

With a 19 mm socket we unscrew the mounting bolt and remove the crankshaft pulley.

With a flat-blade screwdriver and a flat thrust plate made of wood or plywood, we remove the front crankshaft oil seal, as shown in the figure.

With a TORX E20 socket we unscrew the mounting bolts and remove the flywheel and the flywheel locking tool.

With a screwdriver we remove the rear crankshaft oil seal.

With 8 mm, 10 mm and 13 mm sockets we unscrew the timing cover mounting bolts.

We carefully detach the timing drive cover, as shown in the figures.

We check the position of links 1 (figure) of the timing chain relative to marks 2 on the crankshaft sprocket, the camshaft sprocket and the phase regulator.

The difference in the position of the chain links relative to all three marks must be the same.

We push the chain tensioner plunger into the tensioner body by pressing on shoe 1.

We secure the plunger by inserting a piece of 2.5 mm diameter steel wire 2 into the tensioner body hole.

With an 8 mm socket we unscrew the mounting bolts and remove the tensioner, preventing the plunger from being released.

We remove the timing chain tensioner shoe.

With a 10 mm socket we unscrew the mounting bolts and remove the timing chain guide.

We remove the timing chain from the engine.

We turn the oil pump drive chain tensioner 1 (figure) anticlockwise.

We remove the oil pump drive chain tensioner from the shaft and the tensioner spring 2 from the cylinder block.

With a 10 mm wrench and a TORX E8 socket we unscrew the oil pump drive sprocket nut 1.

We remove the oil pump drive sprocket 2 together with the pump chain 3 as an assembly.

With a universal puller we remove the crankshaft sprocket.

With a 10 mm socket we unscrew three mounting bolts and remove the oil pump from the cylinder block.

We unscrew four water pump mounting bolts, remove the water pump and the gasket.

With a 10 mm socket we unscrew two alternator mounting bolts and remove the alternator from the engine.

We unscrew three air conditioning compressor mounting bolts and remove the compressor from the engine.

We unscrew four auxiliary unit bracket mounting bolts and remove the bracket.

With a 12 mm socket we unscrew two bolts 1 (figure) of the thermostat cover mounting, remove the oil level dipstick tube clip, the thermostat cover 2 and take the thermostat valve out of the cylinder block.

With a 10 mm socket we unscrew the knock sensor mounting bolt 1 (figure) and remove sensor 2.

With a 22 mm wrench we unscrew oil pressure sensor 3 from the cylinder block.

With a special wrench we unscrew and remove the oil filter.

With a 19 mm ring wrench we unscrew the temperature sensor from the coolant outlet pipe.

With a 10 mm socket we unscrew seven coolant outlet pipe mounting bolts, remove the pipe and the gasket.

We unscrew the crankshaft position sensor mounting bolt and remove the sensor.

We unscrew the upper intake manifold heat shield mounting bolts and remove the shield.

With a 22 mm nut wrench we unscrew the oxygen sensor from the exhaust manifold.

With a 10 mm socket we unscrew five exhaust manifold mounting nuts, remove the manifold and the gasket.

We unscrew the lower exhaust manifold heat shield mounting bolts and detach the shield from the manifold.

With a 22 mm wrench and a 13 mm socket we unscrew the phase regulator and camshaft sprocket mounting bolts, holding the camshafts with a wrench.

We remove phase regulator 1 (figure) and sprocket 2.

With an 8 mm socket we unscrew nineteen camshaft bearing cap mounting bolts and remove the caps.

We remove the camshafts.

With a 10 mm internal hex socket we unscrew ten cylinder head mounting bolts, remove the washers, the cylinder head and the gasket.

With an 8 mm socket we unscrew eight oil sump cover mounting bolts and remove the cover.

With a 10 mm socket we unscrew ten cylinder block reinforcement mounting bolts.

We carefully separate the cylinder block reinforcement with a screwdriver, as shown in the figure.

We remove the sealing ring from the cylinder block.

With an 11 mm socket we unscrew the connecting rod cap mounting bolts and remove the caps.

We take the pistons with connecting rods out of the cylinder block from the cylinder head side.

When removing the pistons, take care not to damage the lubrication nozzles.

With a TORX E14 socket we unscrew the crankshaft main bearing cap bolts and remove the caps.

We remove the crankshaft and the thrust half-rings.

After removing the half-rings, they must be marked for their position relative to the cylinder block.

With a Torx T40 socket we unscrew three crankshaft position sensor disc mounting bolts and remove the disc.

After removing all engine parts, we wash, inspect and prepare them for assembly.