oil viscosity TOYOTA RAV4 2006 Service Repair Manual

ENGINE - 2AZ-FE ENGINE
01NEG27Y
Irregularly shaped
outer casting
surface of linerCylinder Block
Liner A
A
A - A Cross Section
01NEG28Y
Water Jacket
Spacer Water Jacket
A - A Cross Section A
A EG-8
The liners are the spiny-type, which have been manufactured so that their casting exteriors form large
irregular surfaces in order to enhance the adhesion between the liners and the aluminum cylinder block.
The enhanced adhesion helps heat dissipation, resulting in a lower overall temperature and heat
deformation of the cylinder bores.
Water jacket spacers are provided in the water jacket of the cylinder block.
They suppress the water flow in the center of the water jackets, guide the coolant above and below the
cylinder bores, and ensure uniform temperature distribution. As a result, the viscosity of the engine oil that
acts as a lubricant between the bore walls and the pistons can be lowered, thus reducing friction.