Ford YS4Z-6049-FA Cylinder Head Assembly

The engine must be completely cool before beginning this procedure. The following procedure describes removing the cylinder head with the intake and exhaust manifolds attached, which may be easier if only the head gasket needs replacement. However, if planning any cylinder head servicing, it is probably easier to first disconnect the intake and exhaust manifolds from the cylinder head, tying them out of the way for separate removal. Begin by placing the No. 1 piston at top dead center, relieving the fuel system pressure, and disconnecting the fuel supply line at the fuel rail. Remove the battery and drain the cooling system. Take off the air cleaner and its outlet tube, label and disconnect the vacuum hoses from the intake manifold and other components, and remove the intake manifold brace. Label and disconnect all electrical connectors attaching the cylinder head to the engine and vehicle, including the two large PCM connectors near the power steering fluid reservoir. Disconnect the throttle cable and detach the cable bracket from the manifold, then disconnect the heated oxygen sensor electrical connector at the cooling fan shroud. Remove the engine oil dipstick tube, accessory drivebelt, alternator, and air conditioning compressor, loosening the accessory bracket's securing bolts. Detach the exhaust manifold from the catalytic converter and disconnect the electrical connectors for the knock sensor and engine oil pressure switch. Remove the timing belt and valve cover, disconnect the coolant hoses from the thermostat housing and throttle body, and loosen the cylinder head bolts in the opposite order of the tightening sequence in several stages. Remove and discard the cylinder head bolts, then remove the cylinder head with the intake and exhaust manifolds attached and the old gasket. Note the locations of the cylinder head dowels, remove them, and clean all traces of old gasket material from the mating surfaces, taking care to avoid scratching the aluminum cylinder head. It is advisable to check the cylinder head gasket surface for warpage while the head is off the vehicle. For installation, place a new head gasket on the cylinder block and locate the cylinder head on the dowels, ensuring any replaced dowels are completely seated and do not protrude excessively. Apply a thin coat of clean engine oil to the threads of new cylinder head bolts, install them, and tighten in stages following the proper sequence. The remainder of installation follows the reverse order of removal steps, after which run the engine and check for leaks.

Be careful when freeing it, as the cylinder head is made of aluminum alloy and can be easily damaged. Avoid leveraging between mating surfaces and try rocking the head free to break the seal.

Repeat the procedure for the remaining valves, ensuring that all components are returned to their original locations without mixing them up.

Gently tap the top of the tool, directly over the retainer, with a light hammer to free the seat.

1. Place the cylinder head upside-down on a bench, with a block of wood at each end to give clearance for the valve stems. 2. Smear a trace of valve-grinding compound on the seat face, and press a suction grinding tool onto the valve head. Grind the valve head to its seat with a semi-rotary action, lifting the valve occasionally to redistribute the grinding compound. 3. When a smooth unbroken ring of light grey matte finish is produced on both the valve and seat, the grinding operation is complete. Do not grind in the valves any further than absolutely necessary. 4. After grinding, carefully wash off all traces of grinding compound using a suitable solvent before reassembly of the cylinder head.

The engine should only be turned in the normal direction of rotation, which is clockwise from the right-hand side of the vehicle.