How to Remove Cylinder Head Assembly For Hitachi ISUZU

This instruction show you guide on how to remove cylinder head assembly for Hitachi ISUZU 4HK1 stage-v engine.

Procedures:
1 Battery Ground Cable Disconnect
Disconnect the battery ground cable from the battery.
Caution: Do not disconnect the battery cable for 3 minutes after turning OFF the ignition switch.

2 Coolant Drain
1)Remove the radiator cap from the radiator.
Caution: Do not loosen the radiator cap or sub-tank cap when the coolant temperature is high.
Caution: Because steam and boiling water can burst out from the radiator and possibly cause burns, check that the engine has cooled.
2)Remove the drain plug from the radiator.
3)Drain coolant from the radiator.
4)Loosen the air bleeding plug using a wrench.
Note:If there is an air bleeding plug for the EGR cooler, loosen the plug.
Note: With the pressurized reserve tank specification, it is not necessary to bleed the air.

5)Remove the drain plug from the cylinder block.

6)Discharge coolant from the engine.
7)Install the drain plug to the cylinder block.
8)Install the drain plug to the radiator.

3 Engine Harness Disconnect
1)Disconnect the engine harness from the engine assembly.
Note: Disconnect each connector.

4 Turbocharger Assembly Removal
1)Remove the air cleaner duct from the air cleaner assembly and the turbocharger assembly.
2)Remove the air intake hose from the turbocharger assembly and the intercooler.
3)Remove the exhaust pipe from the turbocharger assembly.
4)Disconnect the oil feed pipe from the turbocharger assembly.
Note:Remove the clip.
5)Remove the oil feed pipe from the oil port cover.
Note:Remove the clip.
6)Disconnect the oil return pipe from the turbocharger assembly.
7)Remove the oil return pipe from the cylinder block.

8)Disconnect the water return pipe from the turbocharger assembly.
9)Remove the water return pipe from the water pump assembly.
Note:Remove the clip.
10)Disconnect the water feed pipe from the turbocharger assembly.
11)Remove the water feed pipe from the cylinder block.
Note:Remove the clip.

12)Remove the exhaust manifold stay from the cylinder block and the turbocharger assembly.

15)Remove the turbocharger assembly from the exhaust manifold.
Note:Remove as a set with the intake duct.

5 EGR Gas Temperature Sensor 1 Removal
1)Disconnect the harness connector from EGR gas temperature sensor 1.
2)Remove EGR gas temperature sensor 1 from EGR pipe A.

6 EGR Gas Temperature Sensor 2 Removal
1)Disconnect the harness connector from EGR gas temperature sensor 2.
2)Remove EGR gas temperature sensor 2 from EGR pipe C.
3)Remove the harness bracket from EGR pipe C.
Note: Remove together with the clip.

7 EGR Removal
1)Disconnect the water rubber hose from the EGR cooler.

2)Remove the EGR heat protector from EGR pipe A.
3)Remove the EGR pipe A from the EGR cooler A and exhaust manifold.
4)Remove EGR cooler A from EGR pipe B.

5)Remove EGR pipe B from EGR cooler B and the EGR rear bracket.
6)Remove EGR cooler B from EGR pipe C.

7)Remove EGR pipe C from the rear engine hanger bracket and EGR valve.
8)Disconnect the harness connector from the EGR valve.
9)Remove the EGR valve from EGR pipe D.
10)Remove EGR pipe D from the inlet pipe.

11)Remove the rear engine hanger from the rear engine hanger bracket.
12)Remove the rear engine hanger bracket from the cylinder head assembly.

8EGR Cooler Water Pipe Removal
1)Remove the fan guide stay from the fan guide and the fan guide bracket.
2)Remove the fan guide bracket from the cylinder head assembly.

3)Disconnect the radiator upper hose from the water outlet pipe.
4)Remove the air leak pipe from the air leak pipe bracket and EGR cooler water pipe.
5)Remove the EGR cooler water pipe from the engine assembly.
Note:Remove the EGR cooler water feed pipe and EGR cooler water return pipe.

9 Intake Throttle Valve Removal
1)Remove the air duct from the intake throttle valve.
2)Disconnect the harness connector from the intake throttle valve.
Note:Pull the lock operation portion to release the lock.

3)Remove the intake throttle valve from the inlet pipe.

10Inlet Pipe Removal
1)Disconnect the harness connector from the boost pressure sensor/boost temperature sensor.
2)Disconnect the harness connector from the IMT sensor.
3)Remove the harness bracket from the inlet pipe.

4)Remove the inlet pipe from the outer inlet cover.

11Oil Separator Removal
1)Remove the harness bracket from the oil separator.
2)Disconnect the oil separator hose from the oil separator.
3)Remove the drain hose from the oil separator and oil level guide tube.

4)Remove the oil separator bracket from the inlet cover.
Note: Remove as a set with the oil separator.

12Oil Level Gauge Guide Tube Removal
1)Disconnect the oil level gauge guide tube from the outer inlet cover.
2)Remove the oil level gauge guide tube from the crankcase.

13 Injection Pipe Removal
1)Remove the clip from the bracket.
2)Remove the injection pipe from the injector and the common rail assembly.
Caution:Do not reuse the removed injection pipe.
Caution:Seal the common rail and injector to prevent foreign material from entering.

14 Fuel Pipe Removal
1)Remove the fuel pipe from the fuel supply pump and the common rail assembly.
Note: Remove the clip.
Caution: Do not reuse the removed gasket.

15 Fuel Leak off Pipe Assembly Removal
1)Disconnect the fuel leak-off pipe from the cylinder head assembly.
2)Remove the fuel leak-off pipe from the fuel supply pump.

Note:Remove the eyebolt tightened together with the fuel feed pipe.
3)Disconnect the fuel leak-off pipe from the common rail assembly.
4)Remove the fuel leak-off pipe from the case.
Note: Remove the clip.

16 Common Rail Assembly Removal
1)Disconnect the harness connector from the fuel pressure sensor.
2)Remove the common rail (fuel rail) assembly from the common rail (fuel rail) bracket.
3)Remove the common rail (fuel rail) bracket from the oil cooler assembly and inlet cover.

17 Cylinder Head Cover Removal
1)Remove the cylinder head cover from the lower cover.
2)Remove the head cover gasket from the cylinder head cover.

18 Lower Cover Removal
1)Disconnect the connector from the lower cover.
Caution: Do not pull the wire, or pry the connector with a screwdriver.
2)Disconnect the injector harness from the injector.
Caution: Do not damage the injector side stud bolt.
3)Remove the injector harness from the cylinder head assembly.
Note:Remove the bracket tightening bolts and then remove the injector harness together with the bracket.
4)Remove the lower cover from the cylinder head assembly.

5)Remove the gasket from the lower cover.
6)Remove the rubber plug from the cylinder head assembly.

19 Injector Removal
1)Remove the injector leak-off pipe from the injector.
2)Remove the injector from the cylinder head assembly.
Note:When it is difficult to remove the injector, use a special tool.

Caution:When removing the injector using the special tool, check that the injector sleeve has not been removed as well.

Caution:Store each ID code plate on the injector head with the cylinder number tag attached to avoid a mix-up.
Caution:Do not damage the injector nozzle.

20 Rocker Arm Shaft Removal
1)Loosen the adjust screw using the wrench.
Note:Loosen all valve clearance adjustment screws.

2)Remove the rocker arm shaft from the cylinder head assembly.
Note:Evenly loosen the rocker arm shaft bracket and the rocker arm assembly bracket tightening bolts from both ends and remove them.
Caution:Do not remove the bolt indicated in the diagram.

21 Camshaft Removal
1)Remove the camshaft bearing cap from the cylinder head assembly.
2)Remove the camshaft bearing from the camshaft bearing cap.
3)Remove the camshaft from the cylinder head.
4)Remove the camshaft bearing from the cylinder head assembly.
Note:Temporarily assemble the removed caps and bearings in the original position to avoid a mix-up after the bearings have been inspected.

22 Bridge Removal
1)Remove the bridge cap from the bridge.
Caution:Do not drop the bridge cap into the engine.
2)Remove the bridge from the bridge guide.
Note:After removing, organize to avoid a mix-up with other installation locations.