Heater Core Case: Service and Repair

Self-made tool







Vehicles with special equipment air conditioning Thickness of sheet metal approx. 0.8 mm

a = 350 mm
b = 70 mm
c = 180 mm
d = 120 mm







NOTE: As from chassis no.201 022 010 239 or 201 024 023 353 the lefthand lower angle bracket has been modified. On these vehicles, items 3/15/16 are no longer required during removal and installation.

Removal







1 Drain coolant.
2 Remove instrument panel
3 Remove cover of air intake
4 Open cable strap on heater box left and unscrew screw on cable connector.







5 Pull plug coupler from blower switch.







6 Pull off vacuum lines on control switches for heating and connections for switch lights.







7 Loosen hose clamp of feed hose on engine and pull off hose.
8 Place container under feed hose







9 Loosen hose clamp of return flow hose and pull off hose.







10 Position compressed air nozzle against return flow hose and blow residual coolant out of heater circuit.







11 Unscrew return flow pipe on heat exchanger and pull off air duct for righthand lateral nozzle on heater box.







12 Unscrew feed pipe on heat exchanger and pull off air duct for lefthand side nozzle.







13 Force-off pipe holder on angle bracket below left.







14 Unscrew nut below left.







15 Loosen hose clamp on feed pipe below air intake and pull off hose.
16 Remove feed pipe toward the rear through front wall.







17 Unscrew nut below right.







18 Unscrew nut at top.







19 Disconnect wire control on slide (1), push back lock (2) and remove actuating control completely from control unit.







20 Disconnect wire control on main air flap, push off clip and pull actuating control out of heater box.
21 Pull heater box at top and below out of screw bolts and remove in upward direction.

Installation







22 Insert heater box.


NOTE: On vehicles with air conditioning as special equipment, insert guide panel between front wall and drain pan, so that the accurate installation position of the drain pan is assured.


23 Pull out guide panel between front wall and drain pan.







24 Clip actuating control to lock (2) and connect wire control to slide (1).







25 Set slide on control Unit to blower stage "4", connect wire control to main air flap, open main air flap up to stop and force holding clamp open.
26 For further installation proceed vice versa.