Discovery 2. Manual — part 11

GENERAL DATA

04-9

Cooling system - Td5

Type

Pressurised, spill return partial flow, thermostatically controlled

Cooling fans

11 blade axial flow on viscous coupling and 11 blade axial flow electric

Electric cooling fan switching points:

For A/C system:

⇒

On

When vehicle speed is 50 mph (80 km/h) or less and ambient
temperature is 28

°

C (82

°

F) or more

⇒

Off

When vehicle speed increases to 62.5 mph (100 km/h) or ambient
temperature decreases to 25

°

C (77

°

F)

For engine cooling during normal running:

⇒

On

110

°

C (230

°

F)

⇒

Off

105

°

C (221

°

F)

For engine cooling at ignition off (to counteract heat
soak):

⇒

On

If, within 10 seconds of ignition off, engine coolant temperature is 105

°

C (221

°

F) or more

⇒

Off

After 10 minutes or if engine coolant temperature decreases to 100

°

C

(212

°

F)

Coolant pump

Centrifugal impeller, belt driven from crankshaft

Thermostat

Waxstat with pressure relief valve

Thermostat opening temperature:

⇒

Initial opening

82

°

C (179

°

F)

⇒

Fully open

96

°

C (204

°

F)

Expansion tank cap relief valve - system operating
pressure

1.4 bar (20.3 lbf.in

2

)

Fuel cooler thermostat opening temperature

82

°

C (179

°

F)

GENERAL DATA

04-10

Cooling system - V8

Type

Pressurised, spill return, thermostatically controlled water and
antifreeze mixture. Vertical flow radiator with remote header tank and
pump assisted

Cooling fans

9 blade axial flow on viscous coupling and 11 blade axial flow electric

Electric cooling fan switching points:

For A/C system:

⇒

On

When vehicle speed is 50 mph (80 km/h) or less and ambient
temperature is 28

°

C (82

°

F) or more

⇒

Off

When vehicle speed increases to (62.5 mph (100 km/h) or ambient
temperature decreases to 25

°

C (77

°

F)

For engine cooling during normal running:

⇒

On

100

°

C (212

°

F)

⇒

Off

94.5

°

C (202

°

F)

For engine cooling at ignition off (to counteract heat
soak):

⇒

On

If, within 10 seconds of ignition off, intake air temperature is 60

°

C (140

°

F) or more and engine coolant temperature is 110

°

C (230

°

F) or more

⇒

Off

After 10 minutes or if engine coolant temperature decreases to 100

°

C

(212

°

F)

Coolant pump

Centrifugal impeller, belt driven from crankshaft

Coolant pump drive ratio

1.293 : 1

Coolant pump output at 1000 rev/min

10 litres/min (2.64 US galls/min) at 0.7 bar (10 lbf.in

2

)

Thermostat

Waxstat with pressure relief valve

Thermostat operating temperature:

⇒

Initial opening

82

°

C (179

°

F)

⇒

Fully open

96

°

C (204

°

F)

Expansion tank cap relief valve - system operating
pressure

1.4 bar (20 lbf.in

2

)

GENERAL DATA

04-11

Clutch - Td5

Type

Diaphragm spring, hydraulically operated with self-centering,
preloaded release bearing

Drive plate diameter

267 mm (10.5118 in)

Pressure plate diameter

267 mm (10.5118 in)

Clutch plate friction material

Verto F202

Diaphragm finger height when clamped on a 8.5 mm
(0.33 in) thick gauge plate

42.5 to 48.5 mm (1.673 to 1.904 in)

Diaphragm finger clearance (service limit)

1.00 mm (0.040 in)

Clutch plate thickness under 6500 N (1461 lb) axial
load:

⇒

New

8.2 to 8.8 mm (0.33 to 0.34 in)

⇒

Service limit

7.0 mm (0.27 in)

GENERAL DATA

04-12

Clutch - V8

Type

Diaphragm spring, hydraulically operated with self-centering,
preloaded release bearing

Clutch plate friction material

APTEC 385

Drive plate diameter

267 mm (10.5118 in)

Pressure plate diameter

268 mm (10.5512 in)

Clutch plate thickness (clamped state)

⇒

New

8.4-8.9 mm (0.33-0.35 in)

⇒

Service limit

7.1 mm (0.28 in)

Rivet depth:

⇒

New

1.73 mm (0.07 in)

⇒

Service limit

0.25 mm (0.01 in)

Clutch plate runout:

⇒

New

0.5 mm (0.02 in)

⇒

Service limit

0.5 mm (0.02 in)