Cummins/Onan — Turbocharger Replacement
Repair & overhaul · Air/exhaust system
From a Cummins/Onan owner's manual covering: GTA8.3, GTA8.3 CD1, GTAR 3. Check it applies to your exact model before use.
Applies to: Cummins/Onan GTA8.3 engine
Before you start
- To prevent bearing damage new turbochargers must be prelubricated before start-up.
- Use only anti-seize compound compatible with oxygen sensors.
Procedure
- Disconnect exhaust and charge air core piping.
- Drain coolant and disconnect turbocharger coolant lines.
- Remove the capscrews from the oil drain tube.
- Remove the oil supply line.
- Remove the intake manifold pressure supply line from the boost capsule.
- Remove the turbocharger and gasket; clean the sealing surface and inspect for damage.
- Install a new gasket and apply anti-seize compound to the mounting studs.
- Install the turbocharger and a new gasket; torque 32 N.m [24 ft-lb].
- Install the drain tube and gasket; torque 24 N.m [18 ft-lb].
- Install the turbocharger coolant lines; keep coolant return line horizontal when tightening.
- Prelubricate new turbocharger: pour 50 to 60 cc [2 to 3 ounces] of clean engine oil into the supply fitting and rotate the turbine wheel.
- Install the oil supply line; torque 15 N.m [11 ft-lb].
- Install the intake manifold pressure supply line.
- Install the charge air core and exhaust piping.
- Operate the engine and check for leaks.
Specs & values
- Turbocharger mounting 32 N.m [24 ft-lb]
- Drain tube 24 N.m [18 ft-lb]
- Oil supply line 15 N.m [11 ft-lb]
- Prelubricate with 50 to 60 cc [2 to 3 ounces] of clean engine oil
Source: Cummins/Onan owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.