Q: How to remove and install Cylinder Head in 4.0L SOHC V6 engine on 1997 Ford Ranger?
A: Care should, however, be taken as removing the heads has to be done when the engine is completely cold to avoid warping. This procedure is rather complex and it is best done with the engine out of the vehicle, mounted on an engine stand; however, it can be done on a running vehicle provided certain special tools and skills are available. In all repair work that is to be done on the cylinder heads, timing chains, and jackshaft chains, the rocker arms and the valve lash adjusters must be pulled out first. First remove the battery negative terminal, then get all the coolant drained then remove the engine from the car for it to be mounted on an engine stand. Following it, you need to uninstall the intake manifold, detail and disconnect wire connectors of fuel injectors, and finally, remove exhaust manifolds. The drive belt and tensioner must be pulled out, and then the rocker arms and the takers together with the lash adjusters. To access the right cylinder head, it is necessary to uninstall the alternator and lower mounting bracket, upper mounting of the radiator hose, cooler bypass hose, coolant temperature sensor, accessory bracket and the thermostat housing as well as the bolts securing the wiring harness for the engine. For the left cylinder head remove the radio capacitor, the ignition coil assembly, and move the accessory bracket to side of the engine but the power steering pump and the air conditioning compressor line remain connected. The hydraulic chain tensioner, the camshaft sprocket bolt and the chain cassette bolt should be removed before lifting the cylinder head(s) off the engine; the latter should be done carefully and the parts should be stored correctly to avoid damage. Prior to assembling the cylinder heads and the block, these surfaces should be free from contamination, and in case of contamination, they should be cleaned, and if possible any materials such as metal scraps found in the cylinders should be evacuated. In special cases, be sure to look for damages in the mating surfaces and chase the threads in the bolt holes. Check that the new gaskets have been correctly located; fit new cylinder head bolts and torque them to the prescribed number of revs. Place and slide the camshaft sprocket over the camshaft and without applying torque on the bolt fix the camshaft chain tensioner bar. Place the engine at the right TDC of cylinder no. 1, fasten the crankshaft holding tool and fit the camshaft holding tool. Torque the camshaft sprocket bolt and fit the hydraulic tensioners in position. Last but not the least, replace the rocker arms and hydraulic valve lash adjusters, revert the steps that were followed for removal, change the engine oil and filter, and crank the engine to look for any signs related to leakage.