belt JAGUAR S TYPE 1999 1.G Powertrain Manual

V6 Engine AJ-V6/AJ28
34Coolant Pump
The coolant pump is fitted via three bolts to the
engine front cover. The pulley is mounted in-
board of the pump assembly, between the pump
and front cover, and has a smooth surface which
is driven from the outer, non ribbed side of the
drive belt.
Coolant returns from the radiator and cabin
heater system are connected via hoses to inlets on
the front of the pump assembly. The outlet from
the pump is connected to the engine block via a
hose and a tubular casting bolted to the top front
of the block between the cylinders.
Radiator and Cooling Fan Assembly
The engine radiator is one component of the
cooling pack assembly which also includes the
PAS and transmission heat exchangers and the
A/C condenser. The cooling pack assembly and
the PAS and A/C systems are described in the
ÔS-TYPE IntroductionÕ Technical Guide and
transmission cooling is described elsewhere in
this Guide.
The radiator consists of an aluminium core,
26mm in thickness, with crimped on plastic end
tanks. A single electrical cooling fan and a fan
D.303.1213
COOLANT PUMP
D.303.1213
D.303.1375
RADIATOR AND FAN SHROUD ASSEMBLY
D.303.1375
Fan Speed
Regulator Module

V6 EngineAJ-V6/AJ28
37
Front End Accessories Drive
D.303.1349
Drive Belt
A single six ribbed belt is driven from the
crankshaft damper pulley to drive the coolant
pump, generator, PAS pump and A/C pump. The
drive belt run is guided via two idler pulleys and
an automatic belt tensioner.
PAS Pump
Generator
D.303.1349
ENGINE ACCESSORIES AND DRIVE BELT
Coolant Pump
A/C Compressor
Drive Belt
Tensioner
Crankshaft
Damper Pulley
Idler pulley
Idler pulley

V6 Engine AJ-V6/AJ28
38
J.303.1348
Generator
The 120AH generator is fitted with a special casing
to enable it to be bolted directly to the engine via
three fixing points.
On the manual transmission vehicles, sudden
deceleration may result in generator momentum
driving the belt against the engine which is
slowing down, with possible effects on the life of
the drive belt. The generator pulley fitted to the
manual transmission vehicle incorporates a clutch
mechanism which allows it to freewheel in the
reverse drive (anti-clockwise) direction. Note that
a special tool is required to remove the pulley.
To improve generator control on all
engine/transmission variants, the generator now
has a four pin connector to provide two new
sensing signals:
¥ pin S is directly connected to the battery to
provide voltage feedback to the regulator
¥ the regulator senses field current and
produces a PWM signal from pin FR to the
PCM to indicate the generator duty cycle.
D.303.1350
DRIVE BELT TENSIONER
GENERATOR
D.303-1350
Drive Belt Tensioner
The drive belt tensioner is a similar type to that
fitted to the V8 engines. An index on the
tensioned arm rotates with wear against three
markings on the tensioner spring cap which
indicate the minimum and maximum lengths for a
new belt and the point at which the belt must be
replaced.
Replace Belt
Belt Wear
Indicator
New Belt Maximum Length
New Belt Minimum Length
Manual
transmission
pulleyAutomatic
transmission
pulley
J.303.1348

V8 EngineAJ-V6/AJ28
59
Front End Accessories Drive
The front end accessories drive has a modified
belt run, new type ancillaries and modified
mounting brackets. The belt is changed to a
6-ribbed type and all pulleys are changed to suit.
Idler Pulleys and Tensioner
Two idler pulleys are used, the lower one
mounted on the generator bracket and a new idler
which screws directly into the engine front cover.
The tensioner is mounted on the PAS pump
support bracket.
Generator
The generator is electrically identical to the unit
fitted to the V6 engine but with a different outer
casing which allows it to be mounted via a similar
(not identical) bracket to the AJ27 unit.
J.303.1394
J.303.1394
PAS Pump
Generator ENGINE ACCESSORIES AND DRIVE BELT
Coolant Pump
A/C Compressor
Drive Belt
Tensioner Crankshaft
Damper Pulley Idler pulley
Idler pulley