Compressor/Pump: Service and Repair

R AND R PRESSURE OIL PUMP





Note
As a spare part, the pressure oil pump is available only in the version for hydropneumatic suspension. part No.117 230 OD 64. Pump is marked with the letters HPF-E on front bearing cap adjacent to production code number and with a blue dot (arrow).

Attention!
Pressure oil pumps MB and Teves operate on self-lubrication, that is, the delivered oil serves simultaneously as lubricant.

In the event of a defect on level control system which leads to complete loss of hydraulic oil, and when vehicle cannot be repaired immediately, make sure that pressure oil pump Teves is not drawing any air. If required, remove driver of pump drive.

On engines 615, 616, 617 and 117 do not remove driver with pressure oil pump MB in the event of a defect on level control system, since otherwise the running engine will damage the intermediate gear shaft and the camshaft of the pump.

Removal





1 Disconnect expanding hose of pressure line (B1) and hose of suction line (A) on pressure oil pump. Close connection of suction line by means of plug.





2 Loosen four hex. socket screws for fastening pump to cylinder crankcase or cylinder head, pull out pump and remove.

Attention!
Never release the two hex. socket screws for fastening cover to pump housing, since otherwise pump may start leaking.

Distinguishing mark of screws: The hex. socket screws for cover are provided with continuous threads visible between cover and housing.

Engine 103





3 Unscrew wing nut or vent cap (35g) from pump housing and remove closing cap.

4 Unscrew hex. nut, remove plastic sleeve from stud.





5 Remove compression spring and filter element from fluid reservoir and suck off oil by means of a syringe.





6 Loosen high-pressure expanding hose (29) and return flow hose (28).





7 Loosen suction line (A) from fluid reservoir and pressure line (B1) to level controller. Pinch suction line with a hose clamp so that the fluid reservoir will not run dry.

8 Slacken single-belt drive.





9 Unscrew hex. screws (41) for fastening pulley and remove pulley from drive shaft.





10 Unscrew hex. screws (36).





11 Remove power steering pump.

116, 117 Engines





12 On engines 116, 117, remove ignition distributor, additionally loosen tensioning roller on engines with air-conditioning or automatic climate control and push in downward direction. To remove suction line (A), loosen holder on cylinder crankcase.





Note: On vehicles with diesel engine 615, 616 and 617, the location of the pressure oil pump on cylinder head, as well as the suction and pressure line connection on pressure oil pump have been changed since February 1979 by displacing the fluid reservoir from the left to the right engine compartment.

The HP expanding hose with steel line to pressure oil pump installed from February to end of May 1979 is no longer available as a spare part.

In the event of repairs, these vehicles should therefore be converted to the third version.

Installation

13 Check driver and coupling members for pump drive.





14 Mount new gasket (1d), introduce pump, making sure that driver components are correctly meshing. Tighten hex. socket screws uniformly to 11 Nm.





15 Connect suction line (A) and pressure line (B1).

103 Engine:

Note: Make sure that a power steering pump is installed, the pressure relief valve of which opens at 82 bar. The opening pressure of the pressure relief valve is stamped into type rating plate of pump. In addition, the type rating plate has a blue background.





16 Fasten power steering pump to carrier. Tightening torque of hex. screws (36) 25 Nm.





17 Fasten pulley to input shaft. lighten hex. head screws to 25 Nm.





18 Connect high-pressure expanding hose (29) to power steering pump. Tighten coupling screw of hose by means of open box wrench insert or open box wrench (072) to 25 Nm.





19 Connect pipe elbow (28) including return flow hose to power steering pump. Tightening torque of coupling nut 35-40 Nm.

20 Connect suction line (A).

21 Connect pressure oil line (B1).

22 Use new sealing rings. Tightening torque of hollow screw 25-30 Nm.

Note: Pay attention to perfect hose installation of all hoses.

23 Mount V-belt and tension.





24 Insert filter element or steadying plate into fluid reservoir, mount compression spring with locking spring or plastic sleeve and hex. nut.

25 Fill specified oil into fluid reservoir. Top-up oil with engine running.

26 Turn steering several times completely to the left and right to vent the system.

Check oil level and power steering system for leaks. Procedures


Note: With cold oil, the oil level should be 6-8 mm below mark.

28 Install ignition distributor on engines 116, 117. On engines with air-conditioning or automatic climate control, tension V-belt of refrigerant compressor.

29 Set firing point.

30 Tighten holder of suction line (A) on cylinder crankcase.