SB214020

PUB TYPE: BULLETIN

NUMBER: SB214020

DATE: 10/25/02

MODEL: E6, E7, E7G, E-TECH™, ASET™

TITLE: TURBOCHARGER PRE-LUBRICATION PROCEDURES

 

 

Turbocharger Pre-Lubrication Procedures

(Also applies to Mack Trucks Australia)

Turbochargers operate at very high speeds, temperatures and pressures. Because of this, lubrication of the turbocharger bearings is extremely important, particularly for a turbocharger that has just been installed, and also for a turbocharger that has not been operated for a period of time and the oil has drained from the bearing and shaft surfaces.

When the engine is first started after a new turbocharger has been installed, or after the engine has been sitting without being started for a period of time (approximately 30 days or more), the bearings are basically dry, and damage to the bearings due to lack of lubrication can occur during the first couple minutes of operation. Except in extreme cases, the turbocharger can continue to operate for several thousand miles, but will eventually fail due to the damage caused at the initial start-up.

Additionally, when a turbocharger shaft or bearing fails, the turbocharger oil supply line can become contaminated with debris. Whenever a turbocharger BEARING OR SHAFT FAILURE occurs, it is EXTREMELY IMPORTANT that the oil supply line be removed and thoroughly cleaned.

Cleaning the Turbocharger Oil Supply Line and Pre-Lubricating a New Turbocharger

When replacing a turbocharger due to a bearing or shaft failure, clean the turbocharger oil supply line and pre-lubricate the new turbocharger as follows:

  1. Remove and flush the turbocharger oil supply line with a suitable, clean, non-flammable solvent. Allow solvent to run through the line to flush any debris, then blow the line dry with clean compressed air.

    A turbocharger failure can result in debris contaminating the turbocharger oil supply line. It is EXTREMELY IMPORTANT to remove, flush and thoroughly clean the line prior to installing the replacement turbocharger. Failure to do so can result in debris from the oil line entering the replacement turbocharger, causing damage to the bearings and eventual failure of the replacement turbocharger.

  2. Mount the turbocharger on the exhaust manifold, install the oil drain tube and connect the exhaust pipe. Do not connect the oil supply line or the inlet air duct to the turbocharger.

  3. Pour clean engine oil into the oil inlet port at the top of the turbocharger until overflowing.

  4. Spin the compressor wheel by hand several revolutions and wiggle the shaft back and forth. This will ensure that oil is distributed over all bearing surfaces.

  5. Install the inlet air duct to the turbocharger, but do not connect the oil supply line at this time.

  6. Again, pour clean engine oil into the turbocharger oil inlet port until overflowing.

  7. Install the oil supply line, then start the engine and let it run at an idle. Typically, it should take approximately eight seconds or less for sufficient oil pressure to build. Allow the engine to idle for approximately three minutes before increasing engine speed or driving the vehicle.

Pre-Lubricating a Turbocharger after Sitting Idle for an Extended Period of Time

Before starting the engine on a vehicle that has been sitting for an extended period of time (approximately 30 days or more), pre-lubricate the turbocharger as follows:

  1. Disconnect the oil supply line and the inlet air duct from the turbocharger.

  2. Pour clean engine oil into the oil inlet port located at the top of the turbocharger until overflowing.

  3. Spin the compressor wheel by hand several revolutions and wiggle the shaft back and forth. This will ensure that oil is distributed over all bearing surfaces.

  4. Reconnect the air inlet duct to the turbocharger.

  5. Again, pour clean engine oil into the turbocharger oil inlet port until overflowing.

  6. Reconnect the oil supply line and start the engine. Allow the engine to idle at least three minutes before increasing engine speed or driving the vehicle.