?N63T AND S63T ENGINE: VALVE SEAL REPLACEMENT . This SI provides a new tool and a new procedure for the N63TU valve seals replacement. Please refer to the following applicable SIBs before replacing the valve seals. SI B11 07 11 - Turbocharger Failure: Oil Supply and Return Line Blockage and Proper Repairs SI B11 01 13 - N63 and N63TU Engines: Engine Oil Consumption, Engine Oil Top-ups and Refill Capacity SI B11 03 13 - Engine Oil Consumption (all models) SI B11 04 13 - N63TU Engine: Engine Oil Consumption If the valve seals are leaking, one of the following will help determine if the seals should be replaced. Smoke from the tailpipe when starting or aggressively accelerating and decelerating the engine Excessive engine oil consumption Spark plugs fouled with engine oil.
