Volvo Engine Diesel 5 (VED5) Gen 3

Introduction

The third generation of the Volvo Engine Diesel 5 – hereafter VED5 Gen 3 – was introduced in 2009. Like the VED5 Gen 2 engine, the VED5 Gen 3 had:

• A five-cylinder, open-deck block made from die-cast aluminium, with 81.0 mm bores and a stroke of 93.15 mm for a capacity of 2400 cc;
• Cast iron integral cylinder liners;
• Aluminium alloy cylinder head;
• Transverse cooling of the cylinder head and engine block;
• A single cam belt-drive system for the camshafts and injection pump;
• Four valves per cylinder actuated by roller finger followers;
• An electronically controlled multi-throttle system in the inlet ports for variable regulation of the swirl level;
• Electronically regulated glow plugs for easier starting in cold weather;
• Electronically controlled, cooled Exhaust Gas Recirculation (EGR);
• An oxidising catalytic converter; and,
• A diesel particulate filter (DPF).

Changes for VED5 Gen 3 engine

For the VED5 Gen 3 engine, however, the following changes were introduced:

• Revised intake for optimised control of air delivery to the cylinders;
• For the D5244T10/T11/T15/T16/T17, two-stage turbocharging;
• Revised exhaust ports;
• A third-generation common-rail direct injection system, a more efficient high-pressure fuel pump that was significantly lighter and piezo-electric injectors that provided maximum pressure of 1800 bar;
• A lower compression ratio of 16.5:1, except for the D5244T18 which had a compression ratio of 17.3:1 (the preceding VED5 Gen 2 engine also had a compression ratio of 17.3:1);
• A larger EGR cooler with cooling fins that increased heat dissipation efficiency by 25 per cent. This cooled the recirculated exhaust gases to a significantly lower temperature for reduction of NOx emissions;
• Bosch EDC17 engine management system;
• Engine mountings that were tailored to suit the high torque output of the diesel engine and supplemented with a third torque rod to stabilise the engine during ‘firm acceleration’; and,
• Instead of using an oil dipstick, the driver was alerted via the information display if the oil needed replenishing; the system also specified how much oil was needed.

May 2010: 1984 cc VED5 Gen 3 engines (‘D3’ and ‘D4’)

In May 2010, the VED5 Gen 3 range was expanded with 1984 cc diesel engines; while these engines had the same 81.0 mm bores, stroke was reduced to 77.0 mm. Changes for the 1984 cc diesel engines included:

• Different piezo-electric fuel injectors;
• A ‘fine-tuned’ variable geometry turbocharger to enhance torque at low engine speeds; and,
• Lighter connecting rods. AustralianCar.Reviews, however, understands that these lighter connecting rods were introduced in the 2400 cc VED5 engine in April 2011.

April 2011 update

In April 2011, the following revisions were introduced for the 2400 cc and 1984 cc VED5 Gen 3 engines:

• Weight-optimised camshafts and connecting rods;
• New low-friction piston rings;
• A chain-driven oil pump;
• On-demand operation for the piston cooling valves;
• A new vacuum pump;
• For 2400 cc engines, a lighter type of connecting rod (which AustralianCar.Reviews understands was previously introduced in the 1984 cc VED5 Gen 3 engine); and,
• For models with six-speed manual transmissions, a start/stop function could shut down the engine when the vehicle was stationary in traffic. The engine would then re-start when the driver pressed the clutch pedal.

The more powerful D5244T15 engine – which produced peak outputs of 158 kW and 440 Nm – was also introduced at this time for the Volvo V70, XC70 and S80 models.

From the fourth quarter of 2011, a start/stop function was introduced for 1984 cc VED5 Gen 3 engines that were mated to automatic transmissions.

Sequential twin turbochargers

The D5244T10, D5244T11, D5244T15, D5244T16 and D5244T17 VED5 Gen 3 were fitted with sequential, two-stage turbochargers. In this arrangement, a smaller low-inertia turbocharger was used at lower revs for fast response to quick throttle movements. At higher revs, however, only the larger turbocharger operated to provide more performance. According to Volvo, the result was ‘an immediate response and rapid acceleration at all speeds, with smooth power delivery between the two turbo ranges’. For the D5244T10 engine, peak boost pressure was 1.8 bar.

In addition, sequential turbocharging enabled higher levels of EGR across a wider rev range.

Piezo-electric injectors

The VED5 Gen 3 engines had piezo-electric fuel injectors and a high-pressure fuel pump to achieve an injection pressure of 1800 bar. The piezo-electric injectors could respond twice as fast as conventional solenoid injectors and enabled up to seven separate injections during each operating cycle. This included:

• Short pre-delivery (or pilot) injections at engine speeds above 3000 rpm for a refined engine note; and,
• Extremely short post-delivery injections after the main injection sequence to remove soot particulates in the exhaust gases or for regeneration of the diesel particulate filter.