What was found
ENGINE WAS TORN DOWN, BY AN APPROVED ENGINE SERVICE CENTER, FOR AN AUDIT OF ITS SB AND TBO CONFIGURATION, DUE TO CROSSOVER DUCT/DIFFUSER FAILURE OF ITS SISTER ENGINE ON THE SAME AIRCRAFT. IT WAS FOUND THE MAINTENANCE RECORDS CONCERNING SB STATUS AND TBO STATUS WERE IN ERROR ON THIS ENGINE ALSO AND INSPECTION OF THE CROSSOVER DUCT ASSY IN THIS ENGINE WAS FOUND VERY LOOSE, BUT NOT YET FAILED. FAILURE OF THIS PART WAS IMINENTNENT AND SEALS IN THIS DUCT WERE MOSTLY FAILED, AFFECTING COMPRESSOR AND ENGINE POWER. COMPRESSOR CROSSOVER DUCT/ DIFFUSER POOR CONDITION FOR ENGINE. (K)