CM850 Electronic Control System – 019-388   Turbocharger Control Valve

A small amount of air could possibly be heard escaping from the turbocharger control valve during the turbocharger actuator test. This is a normal condition for the valve to achieve output regulation pressure.

Do not replace the turbocharger control valve for this condition.

The valve should not leak air with the key ON and the engine OFF. If the valve leaks air with the key ON and the engine OFF, the valve is damaged.

NOTE: Removal of the variable geometry turbocharger may be necessary to access and service the actuator. Use the following procedure in Service Manual, ISBe, ISB, and QSB (Common Rail Fuel System), Bulletin 4021271. Refer to Procedure 010-033 in Section 10.

• Drain the coolant. Use the following procedure in the Service Manual, ISBe, ISB, and QSB (Common Rail Fuel System), Bulletin 4021271. Refer to Procedure 008-018 in Section 8.
• Remove the actuator coolant lines. Use the following procedure in the Service Manual, ISBe, ISB, and QSB (Common Rail Fuel System), Bulletin 4021271. Refer to Procedure 011-030 in Section 11

Disconnect the electrical connections from the actuator.

Remove the four capscrews from the dust cover plate.

Remove the cover and gasket.

Discard the gasket.

Remove the three capscrews that attach the actuator housing to the turbocharger.

Remove the actuator assembly and pivot wear block.

Make sure the keyswitch is in the OFF position.

Bleed the air from the turbocharger control valve supply line.

Remove the air lines to the turbocharger actuator and the OEM air supply.

Disconnect the electrical harness from the turbocharger valve.

Remove the two mounting capscrews.

Discard the sealing washers.

Check the actuator lever on the turbocharger for freedom of movement by moving the lever back and forth by hand. The movement must be smooth, with the lever operating properly.

If the lever is stuck or not moving freely, the variable geometry turbocharger must be replaced.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

It is normal for a small amount of air to be heard escaping from the turbocharger control valve. Do not replace the turbocharger control valve for this condition.

Check the air lines for cracks. Replace the air lines if cracks are found.

Check the air lines for contamination or water.

Use compressed air to clean the air lines.

With the actuator removed from the turbocharger, connect the actuator harness electrical connections.

Use INSITE™ electronic service tool to command the variable geometry actuator open and closed.

Observe the movement of the actuator push rod.

Movement must be free and smooth with no binding. If the actuator does not move freely or binds, it must be replaced.

Follow any related turbocharger fault codes.

Install a new pivot wear block and position the actuator on the turbocharger.

Install the two mounting capscrews.

Install four new capscrews, the dust cover plate, and a new gasket.

Tighten the capscrews.

NOTE: If the actuator is replaced, transfer the turbocharger dataplate information onto the new data tag and adhere the tag to the new actuator.

Connect the electrical connections to the actuator.

CAUTION  Do not use any type of thread sealant or thread tape on air lines. The sealant can cause contamination or malfunction of the turbocharger control valve.

Install the two mounting capscrews.

Install the turbocharger control valve outlet fitting into the valve body Port 2.

Install the turbocharger control valve inlet fitting into the valve body Port 1.

Connect the electrical harness to the turbocharger control valve.

Install the air line from the turbocharger actuator to the turbocharger control valve.

Install the air supply line to the turbocharger control valve.

• Install the turbocharger, if removed.
• Install the coolant lines. Use the following procedure in the Service Manual, ISBe, ISB, and QSB , Bulletin 4021271. Refer to Procedure 011-030 in Section 11.
• Fill the cooling system. Use the following procedure in the Service Manual, ISBe, ISB, and QSB (Common Rail Fuel System), Bulletin 4021271. Refer to Procedure 008-018 in Section 8.
• Clear any fault codes.
• Operate the engine and check for leaks.

• Start and operate the engine. Verify proper operation.
• Check for air leaks.