This part of the chapter includes general techniques for disassembling the cylinder head and other engine components.
The information concerns the sequence of preparation for repair and a step-by-step description of the operations for removing and installing engine components, and their verification.
It is not always easy to determine what and where in the engine needs repair: there are too many factors to take into account. High engine mileage is not always a prerequisite for repair, and vice versa, low mileage does not guarantee the absence of the need for repair.
Increased oil consumption indicates the need to pay attention to the condition of the piston rings, valve stem seals and valve guides. When deciding to repair these components, verify that there are no oil leaks. Additional information about the amount of repair can be obtained by measuring the compression in the engine cylinders.
Check the oil pressure with a pressure gauge installed in place of the oil pressure sensor. A low oil pressure indicates worn bearings or damage to the oil pump.
Loss of power, uneven engine operation, bumps and mechanical noises, increased valve train noise and high fuel consumption, as a rule, indicate the need for repair, especially if all these troubles occurred at the same time.
During the overhaul of the engine, pistons and piston rings are replaced, and the cylinders are bored. New main and connecting rod bearings are also installed, and if necessary, the crankshaft journals are reground and connecting rod and main bearings of oversized dimensions are installed. Pay special attention to the condition of the oil pump and, if there is doubt about its reliability, replace it. The cooling system hoses, thermostat and water pump must be replaced.
Engine repair is not difficult if all work is done carefully and you have the necessary tools and equipment.