How are Turbocharger Assembly issues diagnosed?
Turbocharger diagnosis is a matter of pressure testing, visual inspection, and oil or coolant consumption data. Many times, a turbocharger may be failing, but several other components must be ruled out because there are no additional symptoms besides oil consumption. In the event that a turbocharger is making noise, the turbocharger will be removed and inspected with a dial indicator for the amount of play in the shaft. The impeller and compressor wheels will be inspected for degradation or damage from debris, and the turbocharger piping will be pressure tested. In the most difficult cases of diagnosis, the compressor side of the turbocharger assembly may be pressure tested, but this provides very limited data, and magnaflow testing is often a better option to identify if there are any cracks in the turbocharger housing. Finally, the presence of oil in the turbocharger downpipe is a giveaway that the turbocharger has lost its oil seal, and wear patterns on the impeller, compressor wheel, inside the turbo housing, and around the wastegate are all signs of a failed turbocharger. In the most difficult cases, the engine may be compression tested, the PCV valve replaced, and the oil changed and monitored for consumption over a short period of time. In many cases where the turbocharger is suspected of failure, the turbocharger or turbocharger piping is the culprit.
How is a Turbocharger Assembly replaced?
Before removal of the turbocharger or turbocharger assembly can commence, the engine cooling system and oil pan must be completely drained. Afterwards, the cooling and oil lines for the turbocharger can be removed, and the turbocharger assembly, which often includes the exhaust manifold, can be separated from the cylinder head, mounting brackets, downpipe, intake air tube, and finally removed from the vehicle. In some applications, the engine mounts may need to be removed to rock the engine and transmission assembly to a position which allows space for removal. In the most extreme cases, the engine may need to be removed. Installation is the reverse of removal, but the turbocharger must be run for a short time, the engine oil filter changed once more, and all fittings for cooling and oil lines must be retorqued with fresh seals. The exhaust manifold gasket must be replaced, as well as the flange gaskets mounting the turbocharger to the exhaust.