Series 40E Troubleshooting – Section 11.15 Wastegate Actuator Test

Figure 1. Diagnostic Form

The following procedure will lead you through the Wastegate Actuator Test. For a reproduction of the applicable portion of the diagnostic form, see Figure
“Diagnostic Form”

. ‪

Section 11.15.1
Purpose

This procedure will determine the operation of the actuator in conjunction with the turbocharger operation.‪

Section 11.15.2
Test Procedure

Follow these steps to test the operation of the actuator:‪

1. Remove the actuator boost line from the turbo compressor housing.
2. Connect an air regulator with an 0–60 PSI gage to the actuator boost line. See Figure
   “Wastegate Actuator Test”.
   

   1. Air Hose‪	4. Wastegate Housing‪
   2. Dial Indicator‪	5. Wastegate Actuator Rod‪
   3. Turbine Housing‪	6. Air Pressure Regulator‪

   Figure 2. Wastegate Actuator Test

3. Mark the actuator shaft with the paint pen. Spray leak detector or soap solution around the actuator housing.
4. Spray the leak detector around the actuator housing and slowly apply air pressure to the actuator. The actuator (shaft) movement (indicated by the position of the paint mark, should begin to occur between 28 ± 2 psi.

If a significant amount of actuator shaft movement occurs and no air leaks are detected at the actuator housing, the actuator is okay. If little or no shaft movement occurs or air leaks are present at the actuator housing, the turbocharger must be removed from the engine. Refer to the Series 40E Service Manual
, 6SE0242, for further wastegate diagnosis.‪

Section 11.15.3
Possible Causes

Possible causes for the problem include:‪

• Sticky flapper valve
• Ruptured actuator diaphragm
• Leaky canister
• Leaky hose to actuator

Section 11.15.4
Tools Required

Air pressure regulator, 0–60 psi gage and paint marker (Alternative, a Dial Indicator)‪