The turbocharger (turbo-supercharger) is removed during engine repair, gasket replacement, and when replacing the turbocharger itself.
The turbocharger must not be dismantled or repaired.
The condition of the turbocharger should be checked by the rotor run-down time when the diesel engine is stopped.
To do this, after 3…5 minutes of operation at minimum idle speed, the diesel engine is brought to maximum speed, after which the fuel supply is cut off.
The rotation of the turbocharger rotor after the diesel engine stops should be audible for at least 5 seconds.
A steady, constant-level sound with gradual fading indicates a normal condition of the turbocharger.
One of the reasons for reduced diesel power and increased smoking may be a decrease in boost pressure due to contamination of the compressor flow section, which can be determined by tight rotation of the rotor.
If the rotor rotates tightly, partial dismantling of the turbocharger and flushing of the compressor section is necessary.
Removing the turbocharger
Disconnect the negative battery terminal.
Clean the surface and fittings of the oil supply to the turbocharger.
Apply penetrating fluid to the nuts and bolts of the turbocharger-to-exhaust-manifold connection.
Remove the air filter.
Remove the air supply hose.
Loosen the clamp securing the pipeline to the turbocharger adapter.
Disconnect the pipeline.
Unscrew the clamp nut securing the catalytic converter inlet pipe to the turbine pipe adapter and slide the clamp along the pipe.
Unscrew the mounting nuts and remove the turbine pipe adapter.
Loosen the securing clamp.
Remove the pipeline adapter from the turbocharger to the intercooler.
Unscrew the bolt securing the oil supply hose holder.
Unscrew the banjo bolt securing the hose end fitting.
Disconnect the hose and remove the sealing washers.
Unscrew the two bolts securing the oil drain pipe flange from the turbine bearing.
Disconnect the pipe from the turbocharger housing.
Unscrew one bolt.
Unscrew the three nuts securing the turbocharger to the exhaust manifold.
Remove the turbocharger.
Check the operation of the wastegate actuator.
To do this, move the rod (arrow in the figure); the valve lever should move smoothly, without jamming, and after releasing the rod it should return to its original position.
Check the adjustment of the wastegate actuator.
In the free state, the valve should be pressed tightly against its seat.
If the valve does not fit tightly against the seat, loosen the lock nut.
By turning the adjusting nut, achieve the required valve position.
After adjustment, tighten the lock nut and check the tightness of the valve seating.
If necessary, remove the oil drain pipe end fitting from the turbine bearing from the hole in the cylinder block.
Install new rubber O-rings on the pipe end fitting.
Disconnect the oil drain pipe flange seal from the housing.
Replace the seal. Clean the mating surfaces of the turbocharger, exhaust manifold and inlet pipe.
Install the turbocharger in the reverse order.
Replace the gasket of the turbocharger-to-exhaust-manifold connection.
Replace the gasket between the turbine adapter.
Assemble all parts in the reverse order.
Before installing the turbocharger, apply a thin layer of graphite grease to the turbocharger mounting studs.
The tightening torque for the three fastening nuts and one bolt securing the turbocharger to the exhaust manifold is 24 N·m.
Materials used and recommendations
Use new gaskets and O-rings when performing the work. For cleaning the mating surfaces, use a cloth and a soft scraper, avoiding the ingress of abrasive particles into the turbocharger flow section. Graphite grease may be used for lubricating the mounting studs. Apply penetrating fluid to the threaded connections of the exhaust system in advance to avoid breaking the studs.
After installing the turbocharger, check the engine oil level and the tightness of the oil pipe connections. Before starting the engine, it is recommended to crank the crankshaft with the starter without fuel supply for 10–15 s to ensure pre-lubrication of the turbocharger bearings. The use of sealant when installing the turbocharger is strictly prohibited: sealant particles can enter the oil passages and damage the unit.