Causes Of Turbo Failure And How To Prevent Them

What are Turbochargers?

Turbochargers also commonly known as “Turbo” are induction machines that increase the efficiency of the internal combustion in a vehicle’s engine by forcing more air into the combustion chamber.

Before you fit a replacement turbo, you first need to determine what caused the turbo to fail. The causes for turbo failures fall under the following five categories:

 

Impact Damage

How do foreign objects damage turbos?

Failure of the turbo can be caused by foreign materials/objects entering the turbine/ compressor, damage can be caused by foreign objects that get pulled into the air intake.

 

What are the causes of impact damage?

• • Items get pulled into the air intake because of the poor quality of a damaged air filter.
  • Small particles enter the intake due to damaged hoses.
  • Gasket material entering the intake.
  • During servicing items such as nuts, bolts, washer, etc are left in the intake pipe during servicing.
  • Broken engine components, e.g. injector nozzle, valves, or particles of the damaged piston.
  • Particles from a former turbocharger failure.

 

 

Prevention of turbo failure caused by impact damage.

• • Ensure all air hoses are in good condition and free from blockages.
  • Always replace old gaskets with new gaskets to ensure a perfect seal.
  • Dispose of the old air filter and replace it with a new air filter.
  • Ensure that there are no turbo/ engine particles in the system from the previous failure, before fitting the replacement.

 

 

Oil Contamination

What causes contaminated oil?

• • A damaged or blocked oil filter.
  • High carbon build-up in the engine can quickly contaminate even new oil.
  • During servicing, accidental contamination of new oil can occur.
  • A malfunctioning oil filter bypass valve.
  • Engine wear, leaving particles in the oil.
  • Degraded oil due to excessive temperatures or extended service intervals.

 

Preventing turbo failure caused by contaminated oil.

• • Ensure new oil and a new oil filter are used when fitting a new turbo., as recommended by the vehicle manufacturer.
  • Ensure the correct oil is used for the engine.
  • Ensure the oil inlet pipes are cleaned/replaced, to eliminate any carbon accumulation or sludge that could enter the turbo.

 

 

Oil Leaks

What causes oil leaks at the compressor end?

• • A Blocked air intake filter.
  • Blocked or damaged air intake pipe or hose.
  • A possible air leak on the intake hoses or a leak at the intercooler.

 

What causes oil leaks at the turbine end?

• • A Leak in the exhaust system.
  • A Leak in the EGR system.

 

What causes oil leaks at both the compressor and turbine end?

• • A restriction can occur in the oil drainpipe from the turbo to the engine.
  • Restriction in the engine breather.
  • Damage to the turbo’s rotating parts, and excessive bearing clearance.
  • Incorrect turbocharger fitted.

 

Preventing turbo failure caused by oil leakage.

• • Ensure there are no blockages/restrictions in the air and oil drain systems.
  • Ensure there are no leaks in the exhaust system.

 

Oil Starvation

What causes oil starvation?

• • The oil level in the sump is low.
  • A flow restriction due to a bent in the oil feed pipe.
  • Carbon build-up in the oil feed pipe.
  • Applying silicone to the oil inlet gasket can cause blockage.
  • Incorrect oil inlet gasket restricting oil supply.
  • A blocked or damaged oil filter.
  • Worn or damaged oil pump.
  • Failure to prime the replacement turbo with oil during fitting.

 

Preventing turbo failure caused by oil starvation.

• • Refrain from using silicone on oil gaskets; it can easily become separated and block oil passages.
  • Ensure the oil inlet pipes are cleaned/replaced, to eliminate any carbon accumulation or sludge that could restrict the oil flow to the bearings.
  • It is important to check the oil pressure and oil supply to the turbo.
  • Always use new oil and new oil filters as recommended by the vehicle manufacturer when fitting a new turbo.

 

Overspeeding

What causes overspeeding?

• • A restriction within the air intake filter, damages or split air hose, incorrect amounts of air allowed into the turbo.
  • A ‘chipped’ engine that is not to standard specification.
  • Tampering with the wastegate.
  • Damaged or worn injectors.
  • Signal loss to the SREA (Simple Rotary Electronic Actuator) for the wastegate or VNT control.
  • Incorrect turbocharger fitted.

 

Preventing turbo failure caused by overspeeding

• •  Ensure there are no leaks or restrictions in the air intake.
  •  Ensure the wastegate or VNT linkage is operating freely.
  •  Make certain that the electronic sensors and ECU are operating correctly.

 

Keeping your vehicle in good condition by following a regular vehicle maintenance schedule to avoid expensive repairs. And remember, if you’re uncertain about how to inspect or replace a vehicle part, be sure to contact a reputable mechanic or service centre for assistance.