Cylinder head (Mitsubishi Space Star)

Fig.4.25. Cylinder head fastening elements: 1- oil supply pipe; 2 - oil return pipe; 3 - Oil return pipe gasket; 4 - sealing ring; 5 - cylinder head mounting bolt, 30 Nm + 100±4° + loosen + 25 Nm + 213±7°; 6 - cylinder head; 7 - cylinder head gasket

Removal

Disconnect the cable from the negative battery terminal.
Remove the lower engine splash shield.
Reduce the pressure in the fuel system.
Drain the coolant from the cooling system.
Remove the plug and drain the engine oil from the engine.
Remove the air filter and air intake pipe.
Remove the catalytic converter.
Remove the exhaust pipe and main muffler.
Remove the timing belt of the gas distribution mechanism drive.
Disconnect the connectors from the camshaft position sensor, fuel pressure sensor, high-pressure fuel pump, fuel temperature sensor, fuel injectors, glow plugs, coolant temperature sensor and EGR solenoid valve (Fig. 4.22).

Fig. 4.22. Cylinder head: 1 - camshaft position sensor connector; 2 - fuel pressure sensor connector; 3 - high pressure fuel pump connector; 4 - fuel temperature sensor connector; 5 - fuel injector connector; 6 - glow plug connector; 7 - coolant temperature sensor connector; 8 - EGR solenoid valve connector; 9 - vacuum hose; 10 - brake booster vacuum hose; 11 - Upper radiator hose; 12 - engine cooling system hose; 13 - heater hoses; 14 - fuel return hose; 15 - fuel supply hose

Loosen the clamp and disconnect the brake booster vacuum hose.
Disconnect the vacuum hoses.
Loosen the clamp and disconnect the upper radiator hose from the cooling system pipe.
Loosen the clamp and disconnect the engine cooling system hose.
Loosen the clamps and disconnect the heater hoses.
Disconnect the fuel supply and return hoses. To prevent dirt and foreign matter from entering the fuel system, plug all open connections in the fuel system.
Unscrew the bolt securing the oil supply pipe. Unscrew the connecting nuts and remove the oil supply pipe.
Remove the two bolts and remove the oil return pipe and gasket
Remove the O-rings from the bottom of the oil return tube.
In the sequence shown in Figure 4.23, loosen and remove the cylinder head mounting bolts in 2 or 3 passes.

Fig. 4.23. Sequence of unscrewing the cylinder head mounting bolts

Warning: New cylinder head bolts must be used during installation.

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.
In several stages, in the sequence shown in Figure 4.24, tighten the cylinder head mounting bolts

Fig. 4.24. Cylinder head bolt tightening sequence

Stages of tightening the cylinder head bolts:

1. Tighten the new bolts to 30 Nm in the sequence shown in Figure 4.24.

2. In the same sequence, tighten the bolts to an angle of 100±4°, for which install a special tool on the wrench that ensures that the bolts turn to a strictly defined angle.

3. Wait 3 minutes to allow the cylinder head gasket to seat.

4. Loosen bolts #1 and 2

5. Tighten bolts No.1 and 2 to 25 N·m.

6. Tighten bolts No.1 and 2 to an angle of 213±7°, for which install a special tool on the wrench that ensures that the bolts turn to a strictly defined angle.

7. Divide the remaining bolts into pairs: bolts #3 and 4, bolts #5 and 6, bolts #7 and 8, bolts #9 and 10. Tighten the bolt pairs according to the recommendations in steps 3, 4, and 5.

Warning: When tightening the cylinder head bolts, they stretch. If the cylinder head bolt is overtightened, replace it with a new one, do not re-tighten.

Install the oil supply pipe and screw on the union nuts. Screw in the oil supply pipe mounting bolt.
Install the oil return pipe and gasket.
Remove the plugs and connect the fuel supply and return hoses.
Connect the heater hoses and secure them with clamps.
Connect the engine cooling system hose.
Connect the upper radiator hose to the cooling system pipe.
Connect the vacuum hoses.
Connect the brake booster vacuum hose.
Reconnect all previously disconnected electrical connectors.
Connect the exhaust pipe and main muffler.
Install the catalytic converter.
Install the air filter and the air intake pipe.
Install the timing belt to drive the gas distribution mechanism.
Install the lower engine splash shield.
Fill the engine with the required amount of recommended engine oil.
Fill the cooling system with coolant.
Connect the cable to the negative terminal of the battery.
Start the engine and check for leaks.