While the repair of turbochargers may be of the same design principle, VNT/VTG turbochargers deserve special attention. It is known that many original manufacturers do not supply spare parts for VNT/VTG types. The assertion that a repair is not possible, or even practically impossible, is wrong.
GARRET (Garret-Advancing Motion) stopped supplying spare parts in 2004. However, spare parts were supplied until 2004.
The problem was not the repair process itself, which is basically the same for the same spare parts for bypass-controlled turbochargers. The problem was the calibration (MinFlow calibration) for VNT/VTG turbochargers.
An exact calibration of VNT/VTG turbochargers is only possible with a FlowBench.
Since 2012, original spare parts for individual VTG types from Garret and BorgWarner have also been supplied.
Various providers offer a lot of regenerated turbochargers at unbeatable prices. With the basic setting methods, deviations from the original manufacturers up to 20% are not uncommon.
Many new parts from small and unknown manufacturers are not calibrated at all. The result is a lack of engine power or boost pressure with other related problem (poor power delivery, short life, engine damage etc.)
The use of a FlowBench is essential for the correct VTG setting. This calibration effort is a sign of quality for every turbocharger repair company. A maintenance engineer who does this effort will hopefully not pay less attention on other aspects of quality assurance during the repair process!
It should be clear that this repair work is not ,,cheap’’ to have, even with regenerated turbochargers, a reasonable quality that does not have to shy away from a comparison with a new part!
