Cylinder heads — removal and installation Ford F150
Wait until the engine is completely cool before beginning this procedure.
Caution: These engines are difficult to work on and require special tools for many procedures. On any procedure involving timing chains, the steps must be read carefully and disassembly must proceed using the special tools, otherwise damage to the engine could result.
Caution: The engine must be completely cool when the cylinder heads are removed. Failure to allow the engine to cool off could result in cylinder head warpage.
Removal
1. Relieve the fuel system pressure (see Fuel and exhaust systems)
2. Disconnect the cable from the negative battery terminal (see Engine electrical systems).
3. Drain the cooling system (see Cooling, heating and air conditioning systems).
4. Remove the valve covers (see Valve covers – removal and installation).
5. Remove the intake manifold (see Intake manifold – removal and installation).
6. Remove the exhaust manifolds (see Exhaust manifolds – removal and installation).
7. Remove the timing chains, tensioners and sprockets (see Timing chains, tensioners and sprockets – removal, inspection and installation).
8. Remove the camshafts (see Camshaft(s) – removal, inspection and installation).
9. Following the reverse of the tightening sequence (see illustration 19a or 19b), use a breaker bar to remove the cylinder head bolts. Loosen the bolts in sequence 1/4-turn at a time. Discard the bolts and obtain new ones for reassembly.
10. Lift the cylinder head(s) off the engine. If resistance is felt, place a wood block against the end and strike the wood block with a hammer. Caution: The cylinder heads are aluminum; store them on wood blocks to prevent damage to the gasket sealing surfaces.
11. If the head sticks, use a prybar at the corners of the cylinder head-to-engine block mating surface to break the cylinder head gasket seal. Do not pry between the cylinder head and engine block in the gasket sealing area.
12. Remove the cylinder head gasket(s). Before removing, note which gasket goes on which side (they are different and cannot be interchanged).
Installation
Caution: New cylinder head bolts must be used for reassembly. Failure to use new bolts may result in cylinder head gasket leakage and engine damage.
13. The mating surfaces of the cylinder heads and engine block must be perfectly clean when the cylinder heads are installed. Use a gasket scraper to remove all traces of carbon and old gasket material, then clean the mating surfaces with silicone gasket remover and a plastic scraper. If there’s oil on the mating surfaces when the cylinder heads are installed, the gaskets may not seal correctly and leaks may develop. When working on the engine block, cover the open areas of the engine with shop rags to keep debris out during repair and reassembly. Use a vacuum cleaner to remove any debris that falls into the cylinders.
Caution: Do not use abrasive wheels or metal scrapers on the heads or block surface; use a plastic scraper and chemical gasket remover, or the head gasket surfaces could have future leaks.
14. Check the engine block and cylinder head mating surfaces for nicks, deep scratches and other damage.
15. Use a tap of the correct size to chase the threads in the cylinder head bolt holes. Dirt, corrosion, sealant and damaged threads will affect torque readings.
16. Make sure the new gaskets are installed on the correct cylinder banks. They are not interchangeable.
i.17 Position the gaskets on the correct cylinder banks, then push them down over the alignment dowels
17. Position the new gasket(s) over the alignment dowels (see illustration) in the engine block.
Caution: The method used for the cylinder head bolt tightening procedure is referred to as «torque-angle» or «torque-to-yield» method. Follow the procedure exactly.
i.18a Cylinder head bolt-tightening sequence
i.18b Mark each cylinder head bolt with a paint stripe and, using a breaker bar and socket, tighten the bolts in sequence to the correct torque angle
18. Carefully position the cylinder heads on the engine block without disturbing the gaskets. Install the NEW cylinder head bolts (the cylinder head bolts are of a torque-to-yield design and they cannot be reused). Following the recommended sequence (see illustration), tighten the cylinder head bolts, in stages, to the torque and angle of rotation listed in this Chapter’s Specifications. If the adapter is not available, mark each bolt with a paint stripe to aid in the torque angle process (see illustration).
19. The remainder of installation is the reverse of removal.
20. Change the engine oil and filter and refill the cooling system (see Tune-up and routine maintenance), then start the engine and check carefully for oil and coolant leaks.