Renault Koleos Service Repair Manual: Turbocharging: Precautions for the repair

M9R

I - TURBOCHARGER: GENERAL INSTRUCTIONS

For the turbocharging pressure regulator check.

II - TURBOCHARGER CIRCUIT DIAGRAM

1. Air filter unit
2. Air flowmeter
3. Compressor wheel
4. Intercooler
5. Inlet distributor
6. Exhaust manifold
7. Turbine wheel
8. Bearing system (bearing + wheel shaft)

1. Air filter box air outlet pipe
2. Turbocharger air outlet pipe
3. Intercooler air outlet pipe

III - APPLICATION CONDITIONS OF INSTRUCTIONS

The instructions below must be followed when replacing a turbocharger due to mechanical damage:

• damage to the bearing system,
• broken shaft or turbine wheel,
• compressor wheel rubbing against the turbocharger casing,
• broken or damaged compressor wheel,
• extensive clogging of the turbine wheel casing (hard deposits).

FOR THE AIR CIRCUIT:

• Consequences:
  • swarf or metal objects in the turbocharger inlet and outlet pipes,
  • oil in the air circuit (collected in the intercooler).
• Risks (after replacing the turbocharger):
  • metal objects sucked in by the compressor wheel (destruction of the turbocharger).

FOR THE LUBRICATION CIRCUIT:

• Consequences:
  • swarf found in the engine oil circuit,
  • circulation of swarf within the circuit.
• Risks (after replacing the turbocharger):
  • premature wear on the bearing system (destruction of turbocharger).

INSTRUCTIONS:

• Drain the engine oil .
• Replace the oil filter.
• Replace the seals and fittings,
• Carry out the following only if the compressor wheel is broken or rubbing against the turbocharger casing:
  • Drain the intercooler,
  • Clean the turbocharger air pipes.

IV - AIR CIRCUIT*: INSTRUCTIONS FOLLOWING MECHANICAL DAMAGE TO THE TURBOCHARGER

Remove the intercooler if fitted to the vehicle.

Turn the intercooler over and allow the oil inside to drain out.

Check that there are no metal objects inside the air flowmeter (2) .

Remove:

• the air pipe(between the air filter unit and the turbocharger) (A) ,
• the air pipe (B) (between the turbocharger and the intercooler).

For air pipes comprising several components:

• mark (10) the fitting position of each component,
• separate all the components.

One by one, clean the pipes removed with the parts washer :

• brush as much of the inside of the pipe as possible (only use brushes with plastic bristles),
• wash plenty of cleaning product from the cleaning station through the pipe,
• allow the cleaned pipe to drain by standing it upright,
• ensure the cleaning product has drained out completely (check areas where liquid may be retained, e.g. gaiters, resonators etc.).

Dry the pipes one by one using a compressed air spray gun.

For pipes comprising several components:

• assemble the components, taking note of their correct fitting position (10) .

Refit:

• the air pipe(between the air filter unit and the turbocharger) (A) ,
• the air pipe (B) (between the turbocharger and the intercooler).

Refit the intercooler, if fitted to the vehicle.

V - LUBRICATION CIRCUIT**: INSTRUCTIONS FOLLOWING MECHANICAL DAMAGE TO THE TURBOCHARGER

Drain the engine oil.

Replace the oil filter.

Only fill the engine with a suitable oil type.

VI - GENERAL INSTRUCTIONS TO BE FOLLOWED WHEN REMOVING A TURBOCHARGER

Always replace:

• the oil supply pipe:
  • if the pipe is blocked, even partially (due to scale, carbonised oil etc.),
  • if the pipe is fitted with self-retaining seals.
• the oil return pipe:
  • if the pipe is blocked, even partially (due to scale, carbonised oil etc.),
  • if the pipe is fitted with self-retaining seals.
• all seals that have been removed,
• all fittings that have been removed.

When starting the engine:

• do not accelerate,
• allow the engine to run for 1 minute, the time taken for the oil circuit pressure to increase (until the oil pressure warning light on the instrument panel goes out),
• accelerate several times at no load,
• check the air circuit and the oil circuit for leaks.