Page 926 of 2490
A coola n
t drain plug is located at the rear of the cylinder block.
Coolant may be drained from the A-bank, by removing the coolant pipe from behind the starter motor.
For vehicles fitted with the cold climate package, a cylinder block heater (shown) replaces the drain plug located on the B-
bank.
Coolant Pump and Flow Control
The coolant pump is fitted between the two cylinder banks, on the front face of the cylinder block.
The pump consists of a housing containing a shaft, with a sh rouded plastic impeller on one end and a drive pulley on the
other.
A pair of roller bearings support the shaft in the housing. A seal behind the impeller prevents coolant from contaminating the
bearings. Should this seal fail, coolant escapes from a witness hole in the housin g indicating that immediate action is
required.
An O-ring and an aluminum-alloy gasket, seal the ports between the pump and the cylinder banks.
Coolant Outlet Duct
Page 1001 of 2490

Engine Cooling - Water Pump4.0L NA V8 - AJ27/ 3.2L NA V8 - AJ26
Re
moval and Installation
Remov
al
1.
O
pen the engine compartment and fit paintwork protection
sheets.
2. Drain the cooling system.
For additional information, refer to Cooling System Draining,
Fillin
g and Bleeding
- Vehicles W
ithout: Supercharger
in
this
section.
3. Sl
acken the three screws which
secure the water pump pulley.
4. CAUTI
ON: When releasing the
belt tension, never apply
any torque in a clockwise direction to the pulley ce ntre bolt (left
hand thread) as it could subsequently loosen.
Remove the drive belt from the generator and accessory drive.
1. Use a spanner e.g. Churchill JD-230 or Snap On XDHM 1415, on the centre bo lt of the belt tensioner
idler pulley, to turn the adju ster assembly to the left
against spring tension.
2. Whilst holding the tensioner against spring tension, remove the drive belt from the generator pulley.
Release the tensioner sl owly and remove the
spanner.
D
isconnect the belt from the ot
her pulleys, as necessary,
to move it clear of the pump pulley.
5. Re
move the pulley from the water pump.
1. Remove the pulley securing screws.
2. Remove the pulley from the water pump.
6. Remove the water pump.
1. Remove the five bolts wh ich secure the water pump.
Page 1002 of 2490
In
stallation
2.
Remove the water pump from the engine.
7. Remo
ve the gasket.
1. Remove and discard the water pump gasket.
2. Remove and discard the water pump O-ring seal.
8. Clean any coolant spillage fro m the engine compartment.
9. Clean all relevant part s and sealing faces.
1. To i
nstall, reverse the removal procedure.
Install a new water
pu
mp gasket and O-ring seal.
2. Tigh ten th
e water pump bolts to 8 Nm + 90°.
3. Tighten the water pump pulley bolts to 10-14 Nm.
Page 1004 of 2490

Engine Cooling - Water Pump4.0L SC V8 - AJ26
Remo
val and Installation
Remov
a
l
1.
Op
en the engine compartment and fit paintwork protection
sheets.
2. Drain the cooling system.
For additional information, refer to Cooling System Draining,
Filling and Bleedin
g
- Vehicles With
: Supercharger in this
section.
3. Remove the supercharger driv e belt. Refer to Operation
18.50.08.
4. Slacken the three screws whi
ch
secure the water pump pulley.
5. CAUTIO
N: When releasing the
belt tension, never apply
any torque in a clockwise direction to the pulley ce ntre bolt (left
hand thread) as it could subsequently loosen.
Remove the drive belt from the generator and accessory drive.
1. Use a spanner e.g. Churchill JD-230 or Snap On XDHM 1415, on the centre bo lt of the belt tensioner
idler pulley, to turn the adju ster assembly to the left
against spring tension.
2. Whilst holding the tensioner against spring tension, remove the drive belt from the generator pulley.
Release the tensioner sl owly and remove the
spanner.
Di
sconnect the belt from the ot
her pulleys, as necessary,
to move it clear of the pump pulley.
6. Remove t
he pulley from the water pump.
1. Remove the pulley securing screws.
2. Remove the pulley from the water pump.
7. Remove the water pump.
Page 1005 of 2490
I
nstallation
1
. Remove the five bolts wh
ich secure the water pump.
2. Remove the water pump from the engine.
8. Re
move the gasket.
1. Remove and discard the water pump gasket.
2. Remove and discard the water pump O-ring seal.
9. Clean any coolant spillage fro m the engine compartment.
10. Clean all relevant part s and sealing faces.
1. To
install, reverse the removal procedure.
Install a new water
pump gasket and O-ring seal.
2. Tigh
ten the water pu
mp securing bolts to 8 Nm + 90°.
3. Tighten the water pump pulley bolts to 10-14 Nm.
Page 1007 of 2490
W
ater Pump Pulley Vehicles Without: Supercharger
26.50.05
Removal
1. Open the engine compartment and fit paintwork protection sheets.
2
. Slacken the three screws which secure the water pump pulley.
3
.
C
AUTION:
When releasing the belt tension, never apply any torque in a clockwise direction to the pulley
centre bolt (left hand thread) as it could subsequently loosen.
Remove the drive belt from the generator and accessory drive. 1. Use a spanner e.g. Churchill JD-230 or Snap On XDHM 1415, on the centre bolt of the belt tensioner idler pulley, to turn the adjuster assembly to the left against spring tension.
Page 1008 of 2490
2.
Whilst holding the tensioner against spring tension, remove the drive belt from the generator pulley.
Release the tensioner slowly and remove the spanner.
Disconnect the belt from the other pulleys, as necessary, to move it clear of the pump pulley.
4.
Remove the pulley from the water pump.
1. remove the pulley securing screws.
2. Remove the pulley from the water pump.
Clean relevant parts and faces.
Installation
1.
Installation is the reverse of the removal procedure. Tighten the pulley securing bolts to 10-14 Nm.
Page 1009 of 2490
W
ater Pump Pulley Vehicles With: Supercharger
26.50.05
Removal
1. Open the engine compartment and fit paintwork protection sheets.
2. Remove the supercharger drive belt. Refer to Operation <<18.50.08>>.
3
. Slacken the three screws which secure the water pump pulley.
4
.
C
AUTION:
When releasing the belt tension, never apply any torque in a clockwise direction to the pulley
centre bolt (left hand thread) as it could subsequently loosen.