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Cooling System

Fig 1: Identifying Cooling System
GLL156955Courtesy of VOLVO CARS CORPORATION

The coolant pump shell is integrated in the timing cover. The pump wheel is still driven by the auxiliary unit's transmission.

The coolant pump pumps coolant through the cylinder block, and also cools the cylinder head, cylinder sleeves, spark plug wells, intake ducts and fuel injection nozzles.

The coolant flows in at the coolant pump and passes through a number of channels before it collects and then flows out to the thermostat housing. If the thermostat housing is closed, the coolant passes via the by-pass channel directly to the coolant pump to then circulate through the cylinder block again.

For the turbocharged engine, the task of the cooling system is to supply the turbocharger with coolant.

Coolant pump and drive gear 

Fig 2: Identifying Coolant Pump And Pulley
GLL177774Courtesy of VOLVO CARS CORPORATION

Alternator/clutch 

Fig 3: View of Alternator and Freewheel
GLL177783Courtesy of VOLVO CARS CORPORATION

The belt pulleys on alternator and intermediate shaft have improved surface treatment.

On the alternator shaft between alternator and intermediate shaft there is a clutch with a freewheel (one-way clutch) at each end. The function is to filter the engine's different irregular shape and thus avoid gear rattle/noise in the geartrain.

In connection with introduction of EHPAS  (electric servo pump), the belt-driven servo pump with its heavy steel belt pulley is discontinued as well as the clutch for the coolant pump. The reduced rotating moment of inertia means more freewheeling, primarily when idling.

To reduce/avoid wear, the drive gears' outer ring (against the one-way clutch's friction band), are treated with nitride.

AC bracket 

Fig 4: Identifying A/C Compressor Bracket
GLL177778Courtesy of VOLVO CARS CORPORATION

The AC compressor's fastening bracket is simplified. Earlier solution with a main bracket and three separate stays, is replaced by a modified bracket which has the front reinforcement stay integrated and a new fastening point in the transmission. The change means, except that the fastener assembly has 9 fewer bolts, that the installation method becomes easier and there is no longer a need for any special tools when assembling.