Pic. 2.2. Valve timing engine 1ZZ-FE
Pic. 2.3. Valve timing engine 3ZZ-FE
Cylinder head cover
Pic. 2.4. cylinder head cover
The cylinder head cover is made of high-strength die-cast aluminum alloy and is lightweight.
The cylinder head cover gasket is made of acrylic rubber, which has excellent heat resistance and durability.
Cylinder head
Pic. 2.5. cylinder head
In order to improve filling, a design with vertical inlets has been adopted.
The design of the cooling jacket channels in the block head has also been changed to increase the cooling intensity.
Under the inlet there is a channel of the cooling jacket.
A truncated cone-shaped combustion chamber has been used to reduce the tendency to knock and improve fuel efficiency.
Cylinder block
Pic. 2.6. Cylinder block
Pic. 2.7. Air channels in the cylinder block
To reduce weight, the cylinder block is made of aluminum alloy.
To reduce noise, increase structural rigidity and strength of connection with the gearbox housing, a single block of crankshaft main bearing caps was used.
In order to avoid thermal deformation, liners made of cast iron are included in the design of the main bearing caps. In addition, an oil filter bracket, an air conditioner compressor bracket, a coolant pump volute, a thermostat housing and a rear oil seal holder are made in the cylinder block.
Above the main bearings of the crankshaft in the cylinder block there are air channels. As a result, uniform air circulation in the lower part of the cylinders is ensured and pumping losses are reduced (counterpressure acting on the piston head during reciprocating motion), thereby increasing the useful power of the engine.
Piston
Pic. 2.8. Piston
Thanks to the use of aluminum alloy, it was possible to ensure small dimensions and weight of the piston.
On the piston crown there are truncated cone-shaped displacers: this design improves the combustion process.
A floating piston pin design is used.
Due to the high accuracy of the cylinder diameter, the pistons are not divided into size groups.
Connecting rod
Pic. 2.9. connecting rod
To reduce weight, the connecting rods are made of high-strength vanadium steel.
The width of the connecting rod bearings is optimized to reduce friction.
The small mass of the connecting rod is also ensured by the use of bolts that lengthen when tightened without nuts.
Crankshaft
Pic. 2.10. Crankshaft
Forged crankshaft (engine 1ZZ-FE) has 5 main journals and 8 counterweights.
Cast crankshaft (3ZZ-FE engine) has 5 main journals and 4 counterweights.
The width of the main bearings is chosen optimally in terms of reducing friction.
The main and connecting rod journals of the crankshaft are machined with high precision. A surface treatment class has been selected to reduce friction.