Remove/install coolant thermostat

AR20.10-P-2460OLB

Remove/install coolant thermostat

4.12.13

ENGINE

651 in MODEL 117, 156, 176, 246

1

Electrical connection

2

Thermostat housing

3

Screw/bolts

R48

Coolant thermostat heating element

Y133

Coolant pump switchover valve

 

Remove/install

1.1

Remove soundproofing

ENGINE 651 in MODEL 117, 176, 246

AR94.30-P-5300NKB

1.2

Remove engine compartment paneling

ENGINE 651 in MODEL 156

AR61.20-P-1105NKB

2

Drain coolant at radiator

AR20.00-P-1142NKB

3

Unclip coolant pump switchover valve (Y133) out of the bracket and push to one side

4

Disconnect electrical connection on coolant thermostat heating element (R48)

 The coolant thermostat heating element (R48) must not be removed from the thermostat housing.

5

Disconnect coolant hoses from thermostat housing (2)

 Installation: Check clamps for damage; replace if necessary.

 Hose clamp pliers

*003589033700

6

Remove screw/bolts (3) and remove thermostat housing (2)

 Installation: Replace sealing ring.

 Bolt, thermostat to cylinder head/coolant pump

*BA20.10-P-1001-01X

7

Install in the reverse order

8

Check cooling system for leaktightness

AR20.00-P-1010NKB

 Coolant pump, coolant thermostat

Number

Designation

ENGINE 651

BA20.10-P-1001-01X

Bolt, thermostat to cylinder head/coolant pump

M6

Nm

9