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Heavy Duty Diesel Engines Level II

HDD 151

Heavy Duty Diesel Engines Level II

HDD 151

Course Description

Prerequisite: HDD 112 with a grade of "C" (2.0) or better. Corequisites: HDD 156 and HDD 204. Practices the service and repair of heavy duty diesel engines. Practices NATEF tasks related to heavy duty diesel engines. (15-50)

Outcomes and Objectives

Complete NATEF tasks related to Cylinder Head and Valve Train as listed below.

Objectives:

  • Inspect cylinder head for cracks/damage; check mating surfaces for warpage; check condition of passages; inspect core/expansion and gallery plugs; determine needed action.
  • Disassemble head and inspect valves, guides, seats, springs, retainers, rotators, locks, and seals; determine needed action. Listen for engine noises; determine needed action.
  • Measure valve head height relative to deck and valve face-to-seat contact; determine needed action.
  • Inspect injector sleeves and seals; measure injector tip or nozzle protrusion; determine needed action.
  • Inspect valve train components; determine needed action.
  • Reassemble cylinder head.
  • Inspect, measure, and replace/reinstall overhead camshaft; measure/adjust end play and backlash.
  • Inspect electronic wiring harness and brackets for wear, bending, cracks, and looseness; determine needed action.
  • Adjust valve bridges (crossheads); adjust valve clearances and injector settings.

Complete NATEF tasks related to Engine Block as listed below.

Objectives:

  • Perform crankcase pressure test; determine needed action.
  • Install and align flywheel housing; inspect flywheel housing(s) to transmission housing/engine mating surface(s) and measure flywheel housing face and bore runout; determine needed action.

Complete NATEF tasks related to Cooling System as listed below.

Objectives:

  • Test coolant temperature and check operation of temperature and level sensors, gauge, and/or sending unit; determine needed action.
  • Inspect and reinstall/replace pulleys, tensioners and drive belts; adjust drive belts and check alignment.
  • Inspect thermostat(s), by-passes, housing(s), and seals; replace as needed.
  • Recover coolant, flush, and refill with recommended coolant/additive package; bleed cooling system.
  • Inspect water pump and hoses; replace as needed.

Complete NATEF tasks related to Air Induction and Exhaust Systems as listed below.

Objectives:

  • Perform air intake system restriction and leakage tests; determine needed action.
  • Perform intake manifold pressure (boost) test; determine needed action.
  • Check exhaust back pressure; determine needed action.
  • Inspect turbocharger(s), wastegate, and piping systems; determine needed action.
  • Inspect turbocharger(s) (variable ratio/geometry VGT), pneumatic, hydraulic, electronic controls, and actuators.
  • Check air induction system: piping, hoses, clamps, and mounting; service or replace air filter as needed.
  • Inspect, clean, and test charge air cooler assemblies; replace as needed.
  • Inspect exhaust manifold, piping, mufflers, and mounting hardware; repair or replace as needed.

Complete NATEF tasks related to Engine Brakes as listed below.

Objectives:

  • Inspect and adjust engine compression/exhaust brakes; determine needed action.
  • Inspect, test, and adjust engine compression/exhaust brake control circuits, switches, and solenoids; determine needed action..
  • Inspect engine compression/exhaust brake housing, valves, seals, lines, and fittings; determine needed action.