Engine Mechanical:
Engine block, cylinder head, pistons, crankshaft, camshafts, timing components, lubrication system, cooling system, fuel injection systems (Bosch LE-Jetronic, Motronic), exhaust systems
Engine Electrical:
Ignition system, starter motor, alternator, engine control unit (ECU), sensors, wiring diagrams
Transmission:
Manual transmission (Getrag 240, 260) and automatic transmission (ZF 4HP22) overhaul, diagnostics, fluid specifications, shift linkage
Drivetrain:
Clutch system, driveshafts, differential, axle shafts, wheel bearings
Suspension:
Front struts, control arms, ball joints, bushings, rear semi-trailing arms, shock absorbers, springs, sway bars
Steering:
Steering rack, power steering pump, steering column, tie rods, steering linkage
Brakes:
Front disc brakes (ventilated), rear drum or disc brakes, brake fluid specifications, bleeding procedures, ABS system (where applicable), parking brake
Electrical System:
Battery, charging system, lighting system (headlights, taillights, interior lights), fuse boxes, relays, horn, wipers, washers, power windows, central locking
Body And Chassis:
Body panel removal and installation, door mechanisms, hood, trunk lid, bumpers, interior trim, sound deadening
HVAC:
Heating, ventilation, and air conditioning (HVAC) system operation, components, refrigerant types, service procedures
Exhaust System:
Catalytic converter, muffler, exhaust manifolds, oxygen sensors (if applicable to variant).
Fuel System Components:
Fuel pump, fuel filter, fuel pressure regulator, injectors, fuel tank, fuel lines.
Cooling System Components:
Radiator, expansion tank, thermostat, water pump, hoses, fan (mechanical or electric).
Maintenance:
Routine checks, fluid changes (oil, coolant, brake fluid, transmission fluid), filter replacements (oil, air, fuel), spark plug replacement, belt inspection and replacement
Diagnostics:
Troubleshooting guides for common drivability issues, electrical faults, component testing procedures, diagnostic trouble codes (DTCs) for early Motronic systems
Repair:
Step-by-step instructions for component removal, overhaul, and reinstallation for all major vehicle systems
Rebuilding:
Detailed instructions for engine and transmission rebuilds, including torque specifications, clearances, and assembly sequences
Troubleshooting:
Systematic approach to identifying and resolving problems with detailed symptom-to-cause tables
Wiring Diagrams:
Comprehensive electrical schematics for all major vehicle systems, enabling efficient fault tracing
Wheel Alignment:
Specifications for camber, caster, and toe angles for both front and rear suspensions.
Lighting System Repair:
Headlight aiming, bulb replacement, repair of wiring for taillights, brake lights, turn signals.
HVAC Service:
Refrigerant system evacuation and recharge (with appropriate tools and training), component replacement (compressor, dryer, expansion valve).
Depth:
Comprehensive (covering everything from basic maintenance to complete engine and transmission overhauls)
Diagnostic Tools:
Covers use of basic hand tools, specialized BMW tools (e.g., valve spring compressors, timing tools), and diagnostic procedures for Bosch Motronic systems.
Torque Specifications:
Precise torque values for all fasteners, critical for engine and chassis assembly.
Oil Change Interval:
Typically every 10,000-15,000 km (6,000-9,000 miles) or annually, depending on driving conditions.
Coolant Flush:
Every 2 years or 40,000 km (25,000 miles)
Spark Plugs:
Inspection every 20,000 km (12,000 miles), replacement typically every 40,000-60,000 km (25,000-37,000 miles) depending on type.
Engine Oil:
API SG, ACEA A2/B2 or equivalent. Viscosity: 10W-40 or 15W-50 often recommended for M20 engines, 5W-30 or 10W-40 for M10. Consult manual for precise recommendations based on climate.
Coolant:
BMW-approved ethylene glycol based coolant (e.g., BMW Antifreeze/Coolant concentrate). Mixture typically 50/50 with distilled water.
Brake Fluid:
DOT 4 or DOT 4 PLUS
Transmission Fluid Manual:
GL-4 or GL-5 rated gear oil. Viscosity typically 75W-90 or 80W-90.
Transmission Fluid Automatic:
ZF TE-ML 04D or similar approved ATF (Automatic Transmission Fluid)
Cooling System:
Radiator leaks, thermostat failures, water pump seal leaks, heater core leaks. M20 engines can be prone to overheating if cooling system is neglected.
Fuel System:
Fuel pump failures, fuel accumulator issues, injector problems, porous fuel lines (especially older rubber ones).
Suspension:
Worn control arm bushings, ball joints, trailing arm bushings (cracked), strut mount failures.
Electrical:
Corroded grounds, faulty OBC (On-Board Computer) displays, intermittent electrical issues due to aged wiring harnesses and connectors, failure of the Motronic control unit.
Interior:
Cracked dashboard, sagging headliner, deteriorating door seals, seized window regulators.
Rust:
Common areas include wheel arches, rocker panels, battery tray, rear strut towers, and around windows.