Remove/install heater unit

AR83.70-P-5302J

Remove/install heater unit

23.07.2019

Model

168.006/009/031/032/033 1# , 168.007/008/131/132/133 1# as of 3/1/01

Retrofitted stationary heater Thermo Top C

3

Coolant outlet line, heater

10

Coupling, control lines

21

Exhaust muffler

4

Coolant feed line, heater

12

Combustion air intake line

A6

Stationary heater unit

6

Heater unit mount

14

Exhaust line

A6m1

Coolant recirculation pump

7

Fuel feed line

16

Exhaust gas line mount

Y23

Fuel metering pump

9

Coupling, power supply

20

Red spacer

 

Remove/install

 Danger

Risk of explosion caused by fuel vapors igniting, risk of poisoning caused by inhaling combustible gases and risk of injury caused by burns during and after operation of heater unit

Do not operate stationary heater, auxiliary heater or engine with heater booster in closed rooms or when refueling. Allow heater unit to cool down after operation and wear protective gloves.

AS83.70-Z-0002-01A

Notes on repairing the stationary heater

AH83.70-P-0001-03D

1

Remove center underfloor covering

AR61.20-P-1105GC

 Warning

Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.

AS20.00-Z-0001-01A

2

Release pressure in coolant circuit

 To do so, turn cap of coolant expansion reservoir to detent position 1.

3

Clamp off coolant feed line, coolant outlet line (4 and 3) and fuel feed line (7)

 Clamp

*000589543700

 Clamp

*000589403700

4

Release exhaust gas line mount (16) on exhaust muffler (21) and detach exhaust gas line (14)

5

Disconnect fuel feed line (7) from fuel metering pump (Y23)

 Collect escaping fuel.

 Clamp

*000589403700

6

Unfasten heater mount (6)

 First loosen nut from stud bolt, then push heater in direction of travel until rubber mounts are exposed.

7

Disconnect coolant lines (4, 3) from heater and coolant circulation pump (A6m1)

 Mark coolant lines for installation. Collect escaping coolant in a clean vessel and, after installation, pour back into coolant expansion reservoir.
Bowden cable pliers for spring bracket clamps

8

Disconnect combustion air intake line (12)

9

Guide heater (A6) out downward and, when doing so, detach couplings (9, 10) of the electrical connection lines

 Tilt heater.

 

Disassemble/assemble

10

Disconnect exhaust gas line (14) from heater (A6)

11

Disconnect fuel line (7) from heater (A6)

12

Disconnect heater holder (11) with fuel metering pump (Y23) and remove stud bolt

 Check stud bolt; replace with new one if necessary.

 Bolt, bracket to heater

*BA83.70-P-1009-01A

13

Install in the reverse order

14

Bleed coolant circuit after installation of heater

AR83.70-P-5302-01E



Check

15

Check fuse assignment of heater (A6) on right in engine compartment



Fuse assignment of fuse and relay box in right engine compartment

GF54.15-P-1256-02B

16

Check cooling system for leaktightness

AR20.00-P-1010GF

17

Commission stationary heater



Start up stationary heater

AZ83.70-P-0008-04A

 The heater (A6) switches off automatically before reaching its operating temperature and cannot be restarted again;

a fault interlock exists:



Override malfunction interlock

AR83.70-P-5302-07A

 Stationary heater

Number

Designation

MODEL 129, 163, 168 with Thermo Top C heater

BA83.70-P-1009-01A

Bolt, bracket to heater

Nm

10