The cylinder head is made of aluminum alloy. The spark plugs are located in the center of the combustion chambers.
The design of the intake manifold of the 3S-FE and 4S-FE engines, with four independent channels of equal length, allows the use of an inertial boost effect.
Exhaust and intake valve springs are made of special carbon steel and have variable pitch to reduce resonance.
Camshafts
The exhaust camshaft of the 3S-FE and 4S-FE engines is driven from the crankshaft by a toothed belt, and the intake camshaft is driven from the exhaust camshaft by gears.
The camshafts have 5 bearing journals. Lubrication of the necks, cams and gears of the camshaft drive is carried out by oil, which enters through the oil channel located in the center of the shaft.
The clearance in the valve drive is adjusted by replacing the shims in the valve lifters. The shims can be replaced without removing the camshafts.
The pistons are made of aluminum alloy.
piston pins - "floating" type.
Compression rings: upper compression ring is made of stainless steel, lower compression ring is made of cast iron.
The oil scraper ring consists of two scrapers and an expander. The oil scraper ring removes excess oil from the cylinder walls, preventing it from penetrating into the combustion chamber. Cylinder block 01 lit from cast iron. Wall length (generatrix) each cylinder is approximately 2 times the piston stroke. The upper part of the cylinder block is covered by the cylinder head, and the lower part of the block forms the engine crankcase, in which the crankshaft is installed. The cylinder block has a cooling jacket through which coolant circulates
The oil pan is bolted to the cylinder block. The oil pan is stamped from steel sheet. The dividing wall inside the oil pan retains enough oil even when the vehicle is tilted. The baffle plate also prevents oil waves from being created when the vehicle is braked hard.