Cylinder head of the 4G13 engine (Mitsubishi Space Star)

Removal

• Disconnect the cable from the negative battery terminal.
• Reduce the pressure in the fuel system.
• Remove the bolts, disconnect the high pressure fuel hose and remove the O-ring seal.
• Loosen the clamp and disconnect the fuel return hose.
• Remove the bolts and remove the engine cover.
• Drain the coolant from the cooling system.
• Remove the plug and drain the engine oil from the engine.
• Disconnect the electrical connectors from the crankshaft position sensor, knock sensor, boost pressure sensor, exhaust gas recirculation solenoid valve, ignition coil, injectors, adsorber cleaning solenoid valve, throttle position sensor, throttle control servo, misfire detection sensor, camshaft position sensor, coolant temperature sensor, temperature indicator sensor cooling liquid and the front oxygen concentration sensor (Figure 3.52).

Fig. 3.52. Cylinder head of the 4G13 engine: 1 - crankshaft position sensor connector; 2 - knock sensor connector; 3 - boost pressure sensor connector; 4 - EGR solenoid valve connector; 5 - ignition coil connector; 6 - injector connectors; 7 - connector of the electromagnetic valve for cleaning the adsorber, 8 - connector of the throttle position sensor; 9- Throttle control servo connector; 10- misfire detection sensor connector; 11 - camshaft position sensor connector; 12 - coolant temperature sensor connector;13 - coolant temperature gauge sensor connector; 14 - Front oxygen concentration sensor connector; 15 - exhaust inlet pipe; 16 - exhaust inlet pipe gasket; 17 - Engine oil level indicator guide tube; 18 - sealing ring; 19 - Upper front timing belt cover; 20 - camshaft pulley; 21 - cylinder head mounting bolt, 49 Nm + loosen + 20 Nm + 90° + 90°; 22 - cylinder head assembly;23 - cylinder head gasket

• Remove the bolt and disconnect the wire connecting the engine cylinder block to the ground.
• Remove the bolts and remove the cylinder head cover.
• Remove the intake manifold.
• Unscrew the bolt and remove the engine cooling system bypass pipe.
• Loosen the nuts and disconnect the exhaust inlet pipe from the exhaust manifold and remove the exhaust inlet pipe gasket.
• Remove the bolt and the engine oil level indicator guide tube together with the sealing ring.
• Remove the bolts and the upper front timing belt cover.
• Remove the timing belt of the gas distribution mechanism drive.
• Turn the crankshaft clockwise using the pulley mounting bolt until the timing mark on the camshaft pulley aligns with the corresponding mark, while the piston of the 1st cylinder will be set at TDC in the compression stroke (fig. 3.48).
• Use soft wire or band clamps to secure the timing belt to the camshaft pulley, which will prevent the belt from shifting relative to the camshaft pulley (fig. 3.49).
• Using special tools MD998719 or MD998754 and MB990767, block the camshaft pulley from turning and unscrew the pulley mounting bolt (see fig. 3.20). Remove the pulley with the toothed belt attached to it from the camshaft.

Warning: Do not turn the crankshaft after removing the pulley from the camshaft.

• With a special tool in 2 or 3 passes in the sequence shown in figure 3.32, loosen and remove the cylinder head mounting bolts. When removing the cylinder head mounting bolts, be careful not to damage or deform the spark plug guide tubes, as they are not replaceable.
• Carefully remove the cylinder head.
• Remove the cylinder head gasket.
• Cover the engine cylinders with a clean, lint-free cloth.

Installation

• Installation is carried out in the reverse order of removal, taking into account the following.
• Degrease the mating surfaces of the block and cylinder head.
• When installing, check that all holes on the gasket and cylinder head match.
• Install the gasket and cylinder head onto the cylinder block.
• Check the condition of the head and cylinder bolts and especially their threads. Measure the length of each bolt without a washer from the underside of the bolt head to the end of the bolt. If the length of the bolts (A, Fig. 3.33) less than 103.2 mm, they can be reused. If any bolt exceeds the specified length, replace all bolts in the set.
• Install washers on the cylinder head under the head mounting bolts, with the rounded side facing up, as shown in Figure 3.33.
• Before installation, lubricate the top surface of the washer and the bolt threads with engine oil.
• Tighten the cylinder head bolts in several stages in the sequence shown in figure 3.34.

• step 1: Tighten to 49 Nm
• step 2: Loosen all bolts completely in the reverse order shown figure 3.34
• step 3: Tighten to 20 Nm
• step 4: Tighten the bolts to a 90° angle. Mark the bolt heads and cylinder head with paint (fig. 3.35)
• step 5: Tighten the bolts another 90° angle. The marks on the bolts and the cylinder head should be in line (fig. 3.35)

Warnings!

• (1) Always tighten the bolt at an angle exactly equal to 90°. Otherwise, the cylinder head mounting bolt may become loose (the reliability of the gas connection will not be ensured).
• (2) If the bolt is turned more than 90°, loosen it completely and repeat all tightening operations.

• Install the camshaft pulley and secure it with the bolt, tightening it to the required torque. Using special tools MB990767 and MD998719 or MD998713, lock the camshaft pulley from turning and tighten the pulley mounting bolt to a torque of 88 N·m (see fig. 3.20).
• Install and bolt the cylinder head cover.
• Install the timing belt to drive the gas distribution mechanism.
• When installing the high pressure fuel hose, lubricate the O-ring with a small amount of clean engine oil (fig. 3.36).

Warning: Do not allow oil to enter the fuel line.

• While slightly turning the flange of the fuel hose to the right and left, carefully insert it into the fuel line so as not to damage the O-ring seal. After installation, check that the hose rotates smoothly in the fuel line.
• If the hose flange jams when turning, damage to the O-ring gasket may occur. Disconnect the flange (complete with hose) from the fuel line and check the gasket for any damage, then insert it back and check that it turns smoothly.
• Install the high pressure fuel hose mounting bolts and tighten them to 8.8 Nm.
• Install the cylinder head cover and secure with bolts, tightening them to the required torque.
• Install the engine oil level indicator guide tube together with a new sealing ring and secure with the bolt.
• Install the power steering pump and bracket.
• Install the exhaust pipe flange onto the exhaust manifold and secure with nuts, tightening them to the required torque.
• Install the intake manifold.
• Fill the engine with the required amount of recommended motor oil.
• Fill the cooling system with coolant.
• Connect the cable to the negative terminal of the battery.
• Start the engine and check for leaks.