Removal and Installation

Cylinder Head: Removal and Installation

Removal

NOTE:

When removing components such as hoses, tubes/lines, etc., cap or plug openings to prevent fluid from spilling.

1) Remove camshaft. Refer to [Camshaft: Removal and Installation] Removal and Installation.
2) Remove intake manifold. Refer to [Intake Manifold: Removal and Installation] Intake Manifold Removal and Installation.
3) Remove exhaust manifold. Refer to [Exhaust Manifold: Removal and Installation [VQ40DE] Exhaust Manifold Removal and Installation ].
4) Remove front final drive assembly (4WD models). Refer to [Front Final Drive Assembly: Removal and Installation] .
5) Remove water inlet and thermostat assembly (left bank). Refer to [Water Inlet and Thermostat Assembly: Removal and Installation] Water Inlet and Thermostat Assembly Removal and Installation.
6) Remove water outlet, water pipe and heater pipe. Refer to [Water Outlet and Water Piping: Removal and Installation] Water Outlet Removal and Installation.
7) Remove cylinder head bolts in reverse order as shown using suitable tool and power tool to remove cylinder heads (right and left banks).





8) Remove cylinder head gaskets.

Inspection after Removal

Cylinder Head Bolts Outer Diameter

- Cylinder head bolts are tightened by plastic zone tightening method. Whenever the size difference between (d1) and (d2) exceeds the limit, replace the bolt with a new one.











- If reduction of outer diameter appears in a position other than (d2), use it as (d2) point.

Cylinder Head Distortion

NOTE:

When performing this inspection, cylinder block distortion should be also checked. Refer to [Engine Unit: Inspection After Disassembly] Inspection After Disassembly.

1) Using suitable tool, wipe off oil, scale, gasket, sealant and carbon deposits from surface of cylinder head.

CAUTION:
Do not allow gasket fragments to enter engine oil or engine coolant passages.

2) At each of several locations on bottom surface of cylinder head, measure the distortion in six directions.











- If measured distortion exceeds the limit, replace cylinder head.

Installation

1) Install new cylinder head gasket.
2) Turn crankshaft until No. 1 piston is set at TDC.





- Crankshaft key should line up with the right bank cylinder center line as shown.
3) Install cylinder head follow the steps below to tighten cylinder head bolts in numerical order as shown.






CAUTION:
If cylinder head bolts are re-used, check their outer diameters before installation. Refer to [Cylinder Head: Removal and Installation] (Cylinder Head Bolts Outer Diameter).





Measure the tightening angle using Tool.















4) After installing cylinder head, measure distance between front end faces of cylinder block and cylinder head (left and right banks).











- If the measured value is out of the standard, re-install cylinder head.
5) Installation of the remaining parts is in the reverse order of removal.

Inspection after Installation

- Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required quantity, fill to the specified level. Refer to [Recommended Fluids and Lubricants [for USA and Canada] [1][2]Maintenance ] (United States and Canada). Refer to [Recommended Fluids and Lubricants [for Mexico] ] (Mexico).
- Use procedure below to check for fuel leakage.
- Turn ignition switch ON (with engine stopped). With fuel pressure applied to fuel piping, check for fuel leakage at connection points.
- Start engine. With engine speed increased, check again for fuel leakage at connection points.
- Run engine to check for unusual noise and vibration.

NOTE:
If hydraulic pressure inside timing chain tensioner drops after removal and installation, slack in the guide may generate a pounding noise during and just after engine start. However, this is normal. Noise will stop after hydraulic pressure rises.

- Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids including engine oil and engine coolant.
- Bleed air from passages in lines and hoses, such as in cooling system.
- After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to specified level, if necessary.
- Summary of the inspection items:






*Power steering fluid, brake fluid, etc.