We have recently witnessed a repetitive issue with Hyundai iLoad and H-1 Diesel vans, often resulting in a blown turbo and heavy smoke emission. We uncovered the chain of events starts with the injector sealing copper washers leaking, the image showing a new washer and the damage caused to the leaking one.
This then allows combustion gases to enter the crankcase, the result being a build up of tiny fragments of carbon in the engine oil, blocking the oil pick up gauze and starving the engine and turbo of oil, in many cases the impeller shaft seizes and breaks resulting in oil entering the intercooler and induction.
The costly repair requiring replacement turbo charger, removal of sump and new oil pick up, removal of injectors, recutting seats on the cylinder head and injector and refitting with new washers, (as above left ) often removal and cleaning of the intercooler and in many cases replacement given the common leakage, thats if you can buy one due to high demand. Following this we now recommend changing the washers as part of the service schedule every 40,000 kms ensuring no further costly repairs.