Lesson 1Air intake path: air filter, intake manifold, and causes of restrictionThis examines the diesel air path from filter to valves, including filter types, housings, pipes, manifolds, swirl aids, common blockages, checks, and upkeep tips.
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 explains high-pressure fuel making and control in diesels, comparing common rail to pump-line-nozzle, and mechanical inline/rotary pumps, timing, pressure handling, and wear signs.
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 covers intercooler role and workings, air-to-air vs air-to-liquid types, pressure drops, dirt build-up, leaks, cleaning, and charge air temp effects on power and smoke.
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 reviews extra diesel parts like EGR and crankcase venting, key sensors (MAP, MAF, coolant temp, oil pressure), and their links to the engine control module.
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 details diesel cooling setup and action, radiator, pump, thermostat, coolant mixes, paths, overheating reasons, plus checks, tests, and prevention steps.
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 spotlights diesel injector build and role, nozzle kinds, spray shapes, opening pressure, wear/coking signs, leak impacts on fumes/power, and simple tests/services.
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 explains turbo build and action, turbine/compressor airflow, bearings, wastegate/variable geometry controls, boost caps, and failures from oil issues or overspeed.
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 describes low-pressure fuel path from tank to filters/separators, stressing dirt control, air entry, blockages, and regular service routines.
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 details diesel oil system design, oil types/additives, pumps, channels, bearings, filters, and how oil pressure is made, checked, and kept to stop wear/heat.
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
