Lesson 1Common heavy-equipment diesel configurations (inline, V, turbocharged)This lesson reviews typical diesel engine setups in heavy equipment used across Eritrea. It compares inline and V-type engines, turbocharged versus naturally aspirated options, and how these choices impact installation space, maintenance ease, and overall performance in rugged terrains.
Inline versus V engine architectureTurbocharged vs naturally aspirated dieselsWet and dry liner block constructionOverhead cam vs cam-in-block layoutsPower density and torque curve traitsService access and packaging concernsLesson 2Fuel system components: tanks, filters, lift pumps, injection pumps, injectorsThis lesson discusses diesel fuel storage and delivery systems from tank to injector in heavy equipment. It explains how each part works, fuel flow routes, pressure levels, filtration methods, common wear problems, contamination risks, diagnostic methods, and safe servicing steps suitable for Eritrean workshops.
Tank design and venting in heavy equipmentLift pumps and low-pressure fuel circuitsFilter types, ratings, and water separationHigh-pressure injection pumps and controlInjector types, spray patterns, and wearFuel contamination causes and diagnosisLesson 3Lubrication system: oil types, filters, oil galleries, pressure systems, contamination signsThis lesson explores the lubrication system from oil sump to engine bearings in heavy machinery. It covers oil types and additives, filter designs, oil passages, pressure management, sources of contamination, oil sampling techniques, wear detection, and recommended service schedules for equipment operating in Eritrea's dusty environments.
Engine oil grades and service ratingsOil pump types and pressure regulationMain galleries, jets, and lube pathsFilter media, bypass valves, and serviceContamination sources and oil samplingLow oil pressure and noise diagnosisLesson 4Air intake and turbocharging: filters, intercoolers, turbocharger diagnosticsThis lesson details air intake routes, filtration systems, and turbocharging in heavy diesel engines prevalent in Eritrea. It includes filter varieties, air cooling methods, turbo parts, boost regulation, failure indicators, and detailed diagnostic procedures for turbochargers to ensure reliable performance.
Air filter types, ratings, and restrictionTurbocharger components and terminologyWastegates, VGTs, and boost controlIntercoolers and charge-air leak testingTurbo failure symptoms and root causesBoost pressure and airflow diagnosticsLesson 5Common failure modes and symptoms mapping (smoke colors, odors, loss of power, overheating)This lesson connects typical diesel engine failures to visible symptoms in heavy equipment. It addresses smoke types, unusual smells, sounds, power reduction, and overheating issues, teaching organized inspection methods to identify causes before major disassembly or advanced testing in field conditions.
Black, blue, and white smoke diagnosisFuel, oil, and coolant odor indicatorsLoss of power under load troubleshootingOverheating and coolant loss patternsAbnormal engine noises and vibrationBasic fault isolation flowchartsLesson 6Engine sensors and controls: MAP/MAP-equivalents, coolant temp, oil pressure, crank/cam positionThis lesson investigates primary engine sensors and control systems in contemporary diesel engines for heavy machinery. It describes MAP sensors, temperature monitors, pressure detectors, speed sensors, basic wiring, ECM functions, common failures, and safe testing methods to read sensor information accurately.
MAP and boost pressure sensor operationCoolant temperature and fan control inputsOil pressure sensing and protection logicCrank and cam position sensor principlesECM strategies for fueling and timingBasic sensor testing with multimetersLesson 7Cooling system: radiators, coolant types, thermostats, water pumps, hosesThis lesson explains the design and function of engine cooling systems in heavy equipment. It includes coolant properties, radiator structures, thermostat operations, pump mechanisms, hose materials, and caps, along with cavitation prevention, electrolysis detection, leak testing, overheating analysis, and routine maintenance practices.
Coolant types, additives, and mixing rulesRadiator construction, flow, and cleaningThermostats, bypass circuits, and testingWater pump design, drive, and failuresHoses, clamps, and pressure cap checksOverheating diagnosis and leak detectionLesson 8Diesel engine thermodynamic principles and four-stroke cycleThis lesson introduces diesel engine thermodynamics and the four-stroke operating cycle. It relates compression ignition, air-fuel blending, and heat management to torque production, fuel efficiency, emissions control, and performance variations under different loads, altitudes, and temperatures typical in Eritrea.
Compression ignition and diesel propertiesIntake, compression, power, exhaust strokesCombustion phasing and pressure curvesAir–fuel ratio, mixture formation, and smokeHeat transfer, efficiency, and power outputEffects of load, altitude, and temperatureLesson 9Exhaust and aftertreatment basics: mufflers, particulate filters, DOC, sensors (if present)This lesson introduces exhaust gas flow and aftertreatment technologies in modern diesel engines for heavy machinery. It explains muffler functions, diesel oxidation catalysts, particulate filters, sensor roles, regeneration processes, backpressure problems, inspection areas, and safe management of heated parts.
Exhaust routing and backpressure effectsMuffler types and noise control methodsDOC function and light-off conditionsDPF loading, regeneration, and ashExhaust temperature and pressure sensorsAftertreatment fault symptoms overview
