4. DISASSEMBLY, INSPECTION AND REASSEMBLY OF ENGINES Point 6 1) Removing pipe seals of 4 valve head. [Disassemble] Take off a rocker arm cover in case of 4 valve head after removing fuel injection pipes and pipe seals. [NOTICE] Attention is necessary because a fuel nozzle is caught in a pipe seal and the pipe seal is dam- aged when a rocker arm cover is lifted with a pipe seal sticking to the rocker arm cover. Insert a minus driver in the slit part of the rocker arm cover, and remove it when removing a pipe seal. [Reassemble] Replace the used pipe seal with a new one when removing a pipe seal.
2) Breather system (A reductor to intake air system of blowby gas) Emitting blowby gas is harmful to natural envi- ronment. Therefore blowby gas reductor is adopted to 82E-5 – 98E-5 series naturally aspi- rated engines as breather system (Turbo- charged engines emit blowby gas). The system of model 3D84E, 4D84E is shown as a representative of that breather system in the right figure. Some of the combustion gas passes through the clearance between the cylin- der and the piston, piston ring, and flows to the crankcase. This is said as blowby gas.
While it passes into the cylinder head and the rocker arm cover, the blowby gas mixes with splash oil, and becomes oil mist-blowby gas with passing through the baffle plate inside a rocker arm cover. And it passes through a diaphragm ass’y, and an intake manifold, and is reduced in the combustion chamber. Pressure inside a crank- case is controlled by the function of the dia- phragm ass’y, and suitable amount of blowby gas is reduced in intake air system. [Disassemble] When a rocker arm cover is taken off, check whether oil or the like enter the diaphragm space from a small hole on the side of a dia- phragm cover or not without disassembling the diaphragm. 4-16 82E-5 – 98E-5 SERIES