While turbochargers are designed to last the life of the vehicle, things can and do go wrong. Like the engine itself, a turbocharger can only live a long and prosperous life if it has clean air and clean oil.
3 Biggest turbo killers:
Turbochargers can spin up to 300,000 rpm and work at temperatures of 950C. Bearings inside the turbocharger work under great stress and shaft spins inside the bearing on thin film of oil. Oil must be present at all times from first rev on the engine. Running the turbocharger without oil just for a second can cause major damage to the shaft.
It is essential to ensure that the oil feed pipe to turbo is clear and clean and oil pump is supplying correct pressure of oil.
Causes of oil starvation.
¬ Low engine oil level in sump
¬ Bent, damaged or restricted oil feed pipe
¬ Carbon deposits in the oil feed pipe
¬ Silicone or other liquid sealant blockage inside oil feed pipe and banjo bolt
¬ Incorrect oil inlet gasket restricting oil supply
¬ Blocked, damaged or poor quality oil filter
¬ Worn or damaged oil pump
¬ Failure to prime the replacement turbocharger with oil
¬ Cold start up, and hot shut down of the engine
¬ Do not use silicone or liquid sealants on oil gaskets as it can spread and block oil passages
¬ Clean or replace oil inlet pipes to remove any carbon deposits, sludge or other debris that can restrict oil flow
¬ Check correct oil pressure and oil supply to the turbocharger
¬ Always use new oil and filters before fitting a replacement turbocharger.
How oil becomes contaminated:
¬ An inefficient or poor quality oil filter
¬ High carbon build-up in engines quickly contaminates new oil
¬ Accidental oil contamination during servicing
¬ Badly functioning oil filter bypass valve
¬ Engine wear and tear, leaving metal fragments in oil
¬ Oil that lost its viscosity through extended service intervals
¬ Always use new oil and oil filter before fitting the new turbocharger
¬ Ensure the oil is correct specification for the engine
¬ Clean/replace oil inlet pipe and any carbon deposits, sludge or foreign objects.
Contaminated oil will score the bearings and shaft, leading to rapid wear and ultimately, turbocharger failure.
FOREIGN OBJECT DAMAGE
Some sources of foreign object damage:
¬ Poor or badly maintained air filters allowing particles through
¬ Damaged connecting hoses allowing particles to enter intake
¬ Gasket fragments entering intake
¬ Objects left in the intake pipe during a service procedure
¬ Debris from a previous turbocharger failure not fully removed
¬ Damaged engine parts such as fragments from injector tips, valves and pistons.
¬ Always fit the correct new air filter
¬ Ensure all air hoses are in good condition
¬ Never use old gaskets to avoid gasket breakup
¬ Never use liquid sealants instead of gaskets
¬ Ensure the system is fully cleaned and all previous debris is removed
Any object sucked into the compressor side of turbocharger will damage it causing loss of boost and whining noise of turbocharger.
Even small items, like sand grain can destroy turbocharger.