Checking and Adjusting Basic Charging Pressure

Checking and adjusting basic charging pressure







1. Remove the bypass pipe with valve, 1 bolt on the Turbocharger intake pipe and 1 hose clip on the Turbocharger delivery pipe.


NOTE: There is an O-ring at the bypass pipe mounting on the compressor inlet.


2. Remove the exhaust Manifold heat shield. The heat shield is attached with a nut and two clips on the underside.
3. Remove the clips from the operating arm with special tools 83 94 538 circlip tool.
4. Clamp the pushrod with pliers 83 94 066 Pliers or a similar tool and loosen the locknut with a 83 94 520 Locknut wrench or the equivalent.







5. Hold the operating arm and undo the pushrod from the operating arm. Secure the Control arm, Otherwise There is risk of it "jumping over".
6. Move the operating arm on the boost pressure Control valve to the "Closed" position and adjust the end piece so that the pushrod can easily be fitted on the operating arm pin.
7. Detach the pushrod from the operating arm pin. Turn the end piece clockwise about 2 turns so that a prestress of 2 mm is obtained. Attach the pushrod to the operating arm pin. Fit the circlip.
8. Detach the hose marked "W" from the diaphragm.







9. Connect the pressure/vacuum pump 30 14 883 Pressure/vacuum pump to the diaphragm and pressure gauge 83 93 514 Boost pressure gauge.
10. Carefully pump up pressure so that the Control rod moves to regulate the Charge pressure.
11. When the Control rod has lust started moving read the pressure on the pressure gauge scale. The pressure should be at least 0.4 bar for low pressure Turbo and 0.45 bar for full Turbo.
12. When the pressure is too low the rod is further shortened until 0.4 respectively 0.45 bar is obtained.







13. Remove the Control rod and coat the pin on the operating arm sparingly with Molykote 1000 (part No.30 20 271) or the equivalent.
14. Fit the Control rod and clip, grip the Control rod to prevent it from moving and lock the nut.
15. Disconnect the pressure gauge and pump.
16. Reconnect the hose to the diaphragm.







17. Fit the heat shield, coat its stud with Molykote 1000 (part no.30 20 271) or the equivalent, and screw on the nut.
18. Lubricate the O-ring with non-acidic vaseline and fit the bypass pipe.
Tightening torque: 8 Nm (6 lb ft)