B5.9G, B5.9LPG – Troubleshooting and Repair Manual – 010-050   Turbocharger Wastegate Actuator

NOTE: The turbocharger must be removed to perform the following maintenance checks.

NOTE: Prior to removal, note position length of the control rod from the boost capsule housing and orientation of the boost capsule hose connector in relation to the mounting bracket.

Remove the retaining clip from the control lever.

Disconnect the boost capsule actuator rod end from the turbocharger wastegate lever. This can be accomplished by applying regulated air pressure to the boost capsule in a sufficient amount to activate control rod movement.

Disconnect the control rod from the turbocharger wastegate lever pin.

CAUTION  Be careful not to bend the control lever.

NOTE: If the boost capsule diaphragm material is ruptured and will not hold air pressure other than by hand, manually pull the control rod outward in order to overcome boost capsule spring tension for removal of the control rod from the turbocharger wastegate lever pin.

Loosen the boost capsule mounting capscrews, disconnect the air supply hose and remove assembly from the mounting bracket.

Note length of adjusting link prior to removal.

Loosen nut and remove the adjusting link end from the boost capsule actuator.

Visually inspect the wastegate actuator hose for cracks or holes. Replace the hose if damaged.

Visually inspect the wastegate mounting bracket, actuator rod, and lever for damage. A bent wastegate mounting bracket, actuator rod, or lever can cause improper operation.

If the wastegate mounting bracket, actuator rod, or lever is bent, it must be replaced.

Attach a dial indicator as shown, so that its shaft is in line with the wastegate actuator rod. Set the indicator to zero, with no air pressure applied to the wastegate capsule.

Connect clean regulated air pressure and a pressure gauge to the capsule. Apply 200 kPa [29 psi] to make sure the wastegate is functioning properly.

The rod should move approximately 5 mm [0.200 in] without any sticking or air leakage.

NOTE: No air should be heard leaking through a functional wastegate capsule.

NOTE: A small amount of travel when air pressure is first applied is normal; the tolerance is being removed from the system.

Replace the actuator if no movement of the actuator rod and lever is detected.

Install the adjusting link end onto the boost capsule actuator assembly. Adjust the rod to approximately the same length as when removed.

Fit the new boost capsule actuator assembly to the actuator mounting bracket and install the mounting capscrews.

NOTE: The wastegate is set accurately from the factory. Adjustment is not necessary unless the capsule is removed.

Connect clean, regulated air pressure to the boost capsule.

Regulate the air pressure to the wastegate capsule according to the following table.

Measure the actuator travel.

CAUTION  Do not pull, or push, or force alignment of the clevis pin.

Adjust the wastegate, if necessary, to achieve specified travel.

• Pull the wastegate lever to the foremost closed position (lever toward boost capsule).
• Adjust the length of the clevis end of the control rod to where the clevis pin hole aligns to the wastegate lever.
• Install the adjusting link and retaining clip.
• After adjustment is completed, tighten actuator rod jam nuts.

Disconnect regulated air pressure line from the boost capsule.

Connect the turbocharger boost line to the boost capsule, and secure the hose clamp.