Cylinder Block
- Cylinder block
- Base plate
- Cast iron liner
- Aluminum coating
- Cast steel liner reinforcements
Overview
Volvo's new Drive-E engines share many common engine parts, such as crankshafts, oil pump, sump, alternator and AC-compressor. Other parts are similar, such as the engine block and the balance module of the motors.
Engine weight
Both Volvo's diesel and petrol engines have high-pressure cast connecting rods. The engine's base plate has cast steel linings and cast iron reinforcements. Diesel and petrol engine blocks are identical, except for the higher height of the block and the heavier cast steel liner for the diesel engine. The casting method, combined with unique design, gives a strong construction with light weight. Only two engine block variants are needed, with the main bearing diameter as the only difference. The transition to the new Drive-E engines has given a weight saving of 30-50 kg.
Engine friction
To minimize bearing sizes, the crankshaft is made of forged steel. The base plate's alignment to the engine block has been improved with new patented position wedges. This has led to improved straightness and roundness of the main bearings. The piston diameter is minimized by use of a fixed bushing. The different petrol engine variants have similar pistons, only the machining of the piston top is different for different compression ratios. Petrol engines with lower power have a shorter piston. The petrol engine variants use the same piston rings and all diesel engine variants use the same piston rings. The piston pins on all petrol and diesel variants are coated with diamond-like carbon (DLC). An improved piston and cylinder bore coating as well as roller bearing camshafts mean that the Drive-E engines have low internal friction.
Cylinder head and valve system
The design of the cylinder heads is based on Volvo's five and six cylinder engines. The main changes are related to friction reduction, increased specific output and the creation of common interfaces for petrol and diesel engines. The petrol engine's cylinder head must be able to withstand a very high thermal load and is therefore made of a heat resistant aluminum alloy. The transverse cooling concept, shared with the diesel engine, provides excellent and consistent cooling.
Petrol
The petrol engines have a system of VVT solenoids (Variable Valve Timing) with service free DLC-coated mechanical tappets. The camshaft front bearing is a roller bearing to reduce friction. The camshafts are made of cast iron which is the best material for use in combination with sliding contact with the DLC coated tappet.
Diesel
The diesel engine has been heat-treated to improve the strength and temperature limit of the material, and thereby withstand a cylinder pressure of 190 bar and high power output. The diesel engines have steel camshafts for reduced weight and increased material hardness.