Lesson 1Air intake path: air filter, intake manifold, and causes of restrictionThis part reviews the diesel air intake route from filter to ports, covering filter materials, casings, pipes, manifolds, and swirl aids, along with typical blockage sources, measurement techniques, and upkeep plans for dusty environments.
Air filter media types and efficiency ratingsFilter housings, pre‑cleaners and snorkelsIntake duct routing, resonators and leaksManifold design, runners, swirl and tumbleSources of restriction, dust and ice buildupMeasuring restriction and service intervalsLesson 2High-pressure injection: common rail vs. pump‑line‑nozzle and mechanical injection pump fundamentalsThis part outlines diesel high-pressure fuel production and regulation, contrasting common rail with pump-line-nozzle systems, and explaining mechanical inline and rotary pumps, timing, pressure management, and usual wear or breakdown patterns.
Common rail layout, pressure control and sensorsPump‑line‑nozzle architecture and timing effectsInline mechanical pump elements and cam profileRotary/distributor pump operation and advancePressure waves, line length and injection shapingTypical high‑pressure leakage and test methodsLesson 3Intercooler function, pressure loss, fouling and cleaning considerationsThis part explains intercooler roles and workings, comparing air-to-air and air-to-liquid types, tackling pressure drops, dirt buildup, leaks, cleaning approaches, and charge-air temperature effects on power and emissions.
Charge‑air cooling benefits and heat transferAir‑to‑air versus air‑to‑liquid intercoolersPressure drop, flow balance and sizingOil fouling, soot deposits and leak pathsCleaning methods, flushing and drying stepsTesting for leaks and performance lossLesson 4Ancillary components: EGR overview, PCV/ventilation basics, sensors relevant to diesel (MAP/MAF, coolant temp, oil pressure)This part examines essential supporting diesel parts, including EGR and crankcase ventilation, plus key sensors like MAP, MAF, coolant temperature, and oil pressure, and their interactions with the engine control unit.
EGR purpose, flow control and cooler issuesPCV and crankcase ventilation arrangementsMAP sensor role, mounting and failure modesMAF sensor types, contamination and testingCoolant temperature and oil pressure sensingSensor data use in diesel ECU strategiesLesson 5Cooling system: radiator, water pump, thermostat, coolant types and causes of overheatingThis part addresses diesel cooling system design and function, including radiator, pump, thermostat, coolant properties, flow routes, and frequent overheating reasons, with checks, tests, and preventive care routines.
Coolant flow path and heat transfer basicsRadiator, fan, shroud and airflow managementWater pump design, drive types and failuresThermostat operation, testing and replacementCoolant types, mixing rules and corrosion controlDiagnosing overheating and hot‑spot conditionsLesson 6Injectors: nozzle types, spray patterns, wear symptoms, and leakage effectsThis part concentrates on diesel injector build and operation, including nozzle varieties, spray forms, opening pressure, wear and carbon buildup signs, leakage impacts on emissions and power, and simple test and maintenance steps.
Pintle, hole‑type and multi‑hole nozzlesSpray pattern, atomization and penetrationInjector opening pressure and pop testingNozzle coking, erosion and seat wearInternal leakage, dribble and misfire effectsBasic cleaning, replacement and codingLesson 7Turbocharger components and operation: turbine, compressor, wastegate/variable geometry basicsThis part details turbocharger structure and function, covering turbine and compressor airflow, bearing setups, wastegate and variable geometry controls, boost caps, and failure signs tied to lubrication or excessive speed.
Turbine housing, wheel design and energy useCompressor maps, surge and choke regionsJournal and ball bearings, seals and coolingWastegate actuators, control lines and tuningVariable geometry vanes, actuators and sootTurbo failure modes, inspection and protectionLesson 8Fuel delivery system: fuel tank, lift pump, primary and secondary filters, and water separatorsThis part outlines the low-pressure fuel supply route, from tank and pickup to lift pump, filters, and water separators, stressing contamination prevention, air entry, blockage diagnosis, and standard service tasks.
Fuel tank design, pickups and return routingLift pump types, priming and failure signsPrimary and secondary filter functionsWater separator design and draining practiceAir leaks, suction restriction and cavitationService intervals and contamination controlLesson 9Lubrication system: oil types, oil pump, galleries, bearings and oil filter functionThis part elaborates on diesel lubrication system layout, oil types and additives, pump varieties, oil passages, bearings, and filtering, showing how oil pressure is produced, checked, and sustained to avoid wear and heat issues.
Engine oil grades, base stocks and additivesOil pump types, drives and pressure regulationMain galleries, branch feeds and priority circuitsBearing lubrication, clearances and coolingOil filter types, bypass valves and serviceLow oil pressure diagnosis and common causes
