Checking and adjusting basic charging pressure (B235R, B205L/R)
- Remove the bypass pipe with valve.NOTE: There is an O -ring where the bypass pipe is fastened to the turbocharger inlet pipe.
- Remove the exhaust manifold heat shield. The heat shield is attached with a nut and two clips on the underside.
- Remove the control arm circlip using 83 94 538 Circlip tool.
- Grip the push rod using 83 94 066 Pliers or the like. Undo the lock nut using 83 94 520 Wrench, lock nut or the like.
- Hold the control arm and detach the push rod. Secure the arm. Otherwise, the control arm may "jump over".
- Move the control arm on the boost pressure control valve to the "Closed " position and adjust the end piece so that the push rod can easily be fitted on the control arm pin.
- Detach the push rod from the control arm pin. Turn the end piece clockwise about 2 turns so that a prestress of 2 mm is obtained. Attach the push rod to the control arm pin. Fit the circlip.
- Detach the hose from the diaphragm box.
- Connect 30 14 883 Pressure/vacuum pump to the diaphragm box as well as pressure gauge 83 93 514 Boost pressure gauge.
- Carefully pump up pressure until the control rod moves to regulate the boost pressure.
- Just as the control rod starts to move, read off the pressure on the pressure gauge. It should be 0.45 bar (+/-0.03 bar).
- Shorten the rod if the pressure is too low until 0.45 bar is obtained.
- Undo the push rod and apply Molykote 1000, part no. 30 20 971, or equivalent to the pin on the control arm.
- Fit the push rod and clip, grip the push rod with a pair of adjustable pliers and lock the nut.
- Remove the pressure gauge and pump.
- Reconnect the hose to the diaphragm box.
- Fit the heat shield.
- Lubricate the O -ring with acid -free vaseline and fit the bypass pipe.
Tightening torque: 8 Nm (6 lbf ft)