How to Performing an Engine Overhaul on a Cessna Citation CJ3+

Disconnect and remove the inlet duct, exhaust tailpipe, and associated clamps to access engine mounting points. Example: Loosen V-band clamps on inlet duct using 7/16 wrench working from bottom clamp counterclockwise, support inlet duct weight to prevent dropping when clamp releases, remove exhaust tailpipe by loosening spring-loaded clamps at turbine outlet - compress springs with pliers while backing out adjustment nuts, inspect duct interiors for foreign object damage or unusual wear patterns that might indicate engine problems, clean duct mounting flanges and inspect for cracks or distortion that could affect sealing, store ducts in protected area to prevent damage during overhaul period, photograph clamp positions and routing for proper reassembly reference, and verify all hardware is accounted for including springs, bolts, and sealing rings.

Systematically disconnect fuel lines, electrical harnesses, and pneumatic connections while documenting routing for reassembly. Example: Disconnect fuel supply line at engine-mounted fuel control unit using proper fuel line wrench to prevent fitting damage, drain residual fuel into approved container following environmental regulations, remove electrical connectors from starter/generator, fuel control, and ignition system - use connector removal tools to prevent pin damage, disconnect pneumatic lines for anti-ice and customer bleed air at quick-disconnect fittings, cap all open lines and fittings immediately to prevent contamination entry, photograph each connection before removal showing wire routing and connector orientation, label each harness and line with removal sequence numbers for installation reference, and store all hardware in organized containers labeled by system and location.

Remove the four main engine mounting bolts connecting engine to wing pylon while supporting engine weight with hoist. Example: Position engine hoist with proper lifting fixture attached to engine lift points specified in maintenance manual, adjust hoist to just take engine weight without lifting - engine should feel supported but still contact mounts, remove safety wire from engine mount bolts using safety wire pliers, apply penetrating oil to mount bolt threads if corrosion is visible, remove lower mount bolts first using 3/4 inch socket with torque multiplier if necessary, remove upper mount bolts while carefully controlling engine position with hoist, inspect mount bolts for stretch, thread damage, or corrosion requiring replacement, examine engine mounts and bushings for wear, cracking, or separation, clean mount bolt holes and apply anti-seize compound during reassembly, and lift engine slowly ensuring all connections are clear before moving away from aircraft.

Conduct comprehensive external inspection and internal borescope examination to assess engine condition and determine overhaul scope. Example: Examine engine exterior for oil leaks, heat distress, impact damage, or unusual wear patterns, inspect compressor inlet for foreign object damage to blades or case, use borescope through igniter ports to examine combustion chambers for cracking, warping, or hot spots, inspect turbine section through exhaust for blade damage, tip rub, or excessive carbon buildup, check oil system for contamination by examining oil filter and magnetic drain plugs, document all findings with photographs showing specific damage locations and severity, compare findings against manufacturer service limits and overhaul requirements, assess whether engine requires hot section inspection only or complete overhaul, review engine logbooks for recurring problems or previous repairs that might affect overhaul approach, and prepare preliminary parts list based on visual inspection findings.

Split engine case into halves using proper fixtures to prevent distortion while removing internal components systematically. Example: Remove accessory gearbox by unbolting mounting flange and lifting away with small hoist, drain all oil from engine case and oil tank into approved containers, position engine in case splitting fixture ensuring proper support at specified lifting points, remove case bolts in reverse order of assembly sequence specified in maintenance manual, use case splitting fixture to apply even pressure while separating case halves - avoid prying or hammering, lift upper case half slowly checking for binding or forgotten connections, photograph internal arrangement before disturbing any components, remove rotor assemblies using proper lifting fixtures - compressor rotor requires different fixture than turbine rotor, inspect case interiors for cracking, fretting, or unusual wear patterns, and store case halves in protective covers to prevent damage during overhaul period.

Remove turbine blades from rotor disk using specialized pullers and perform detailed inspection for serviceability. Example: Remove turbine rotor from case and secure in blade removal fixture, use turbine blade puller to extract blades individually - apply steady pressure to avoid shock loading, inspect each blade for cracks using magnetic particle testing on steel blades or dye penetrant on nickel alloy blades, measure blade chord lengths and tip dimensions comparing to service limits in maintenance manual, examine blade roots for fretting, corrosion, or stress cracking particularly at fir tree contact areas, check blade leading and trailing edges for impact damage, erosion, or thermal distress, inspect cooling holes (if applicable) for blockage or damage using small diameter wire, document blade serial numbers and positions for balanced reassembly if blades are serviceable, segregate blades by condition - serviceable, repairable, or scrap, and store serviceable blades in protective containers to prevent damage during overhaul.

Extract main shaft bearings and examine races, balls, and cages for wear patterns and damage requiring replacement. Example: Remove bearing retaining nuts using proper spanner wrenches - note torque required for removal as indicator of bearing preload, use bearing puller to extract bearings from shafts avoiding damage to bearing races or shaft journals, clean bearings in approved solvent and dry with compressed air - never spin bearings with air pressure, examine ball bearings for pitting, spalling, or discoloration indicating overheating, inspect bearing races for fretting, wear patterns, or cracking using magnifying equipment, measure bearing internal clearances using precision gauges comparing to manufacturer specifications, check bearing cages for cracking, wear, or distortion that could cause bearing failure, lubricate serviceable bearings with preservation oil and store in protective containers, document bearing part numbers, positions, and condition for replacement planning, and inspect shaft journals for scoring, out-of-round, or other damage requiring machine work.

Install new bearings, seals, and refurbished components using proper heating and torque techniques in contamination-controlled environment. Example: Set up clean room tent around assembly area with HEPA filtration running continuously, heat new bearing races to 200°F using bearing heater for proper interference fit installation, install bearings on shafts ensuring proper orientation and seating against shoulders, apply specified sealants to case mating surfaces using thin, even coating, position rotor assemblies in lower case half using proper lifting fixtures and alignment tools, install new seals and gaskets without stretching or distorting sealing surfaces, mate case halves slowly ensuring proper component alignment before applying clamping pressure, torque case bolts to specification using calibrated digital torque wrench in proper sequence, verify rotor turning torque meets specification after case assembly, check all clearances including tip clearances and bearing preloads using precision measuring instruments, and perform assembly leak test using shop air to verify case integrity.