Engine Mechanical:
Detailed overhaul, repair, and troubleshooting for all R129 engine variants.
Engine Management:
Ignition system, fuel injection (KE-Jetronic, LH-Jetronic, ME-Motronic depending on year/engine), emissions control, diagnostics.
Transmission:
Automatic transmission service, repair, and diagnostics (e.g., 4-speed 722.3/722.4, 5-speed 722.5/722.6).
Drivetrain:
Driveshaft, differential, rear axle components, and related systems.
Suspension:
Front and rear suspension systems, shock absorbers, springs, control arms, bushings, and power steering.
Brakes:
Hydraulic system, ABS (Anti-lock Braking System), brake calipers, rotors, pads, lines, and parking brake.
Steering:
Power steering system, steering gearbox, linkages, and column.
Electrical System:
Complete wiring diagrams, battery, charging system (alternator, starter), lighting, fuses, relays, and grounding.
Body Exterior:
Panel removal/installation, bodywork repair, convertible top mechanism and hydraulics, doors, hood, trunk, bumpers.
Body Interior:
Dashboard, seats, upholstery, trim panels, climate control system components, and interior electronics.
HVAC:
Air conditioning system, heating system, climate control unit, blower motor, evaporator, condenser, refrigerant.
Convertible Top System:
Hydraulic operation, motors, cylinders, seals, and control modules for the retractable hardtop.
Safety Systems:
Airbag system, seatbelt pre-tensioners, and related sensors and control units.
Routine Maintenance:
Oil changes, filter replacements, fluid checks and top-offs, spark plug replacement, belt inspection/replacement.
Diagnostic Procedures:
Troubleshooting guides, symptom-based diagnostics, fault code interpretation (where applicable).
Engine Repair:
Top-end rebuilds, bottom-end rebuilds, head gasket replacement, piston and ring replacement, valve adjustments.
Transmission Repair:
Torque converter replacement, clutch pack service, valve body repair, transmission fluid and filter changes.
Brake Repair:
Brake fluid flush and bleed, caliper rebuild, rotor and pad replacement, ABS component testing.
Suspension And Steering Repair:
Component replacement (ball joints, tie rods, control arms), alignment procedures, power steering pump and rack service.
Electrical Repair:
Component testing and replacement (alternator, starter, sensors), wiring harness repair, module diagnostics.
Bodywork And Trim Repair:
Dent removal, panel replacement, convertible top hydraulic system repair, interior trim panel installation.
HVAC Repair:
Refrigerant system service, blower motor replacement, climate control unit repair.
Depth:
Comprehensive, covering everything from basic maintenance to complete engine and transmission overhauls, and advanced diagnostics.
Detail Level:
Step-by-step instructions, detailed photos, and exploded diagrams.
Oil Change Interval:
Typically every 7,500-10,000 miles (12,000-16,000 km) or annually, depending on driving conditions and oil type used. The manual will specify exact intervals based on model year and engine.
Major Service Interval:
Major services often recommended around 30,000 miles (48,000 km), including spark plugs, transmission service, brake fluid flush.
Engine Oil:
API SJ or higher, SAE 0W-40 or 5W-40 synthetic recommended. (Specific MB 229.3 or 229.5 spec might apply to later models, check manual).
Transmission Fluid:
Specific ATF (Automatic Transmission Fluid) is critical. For 722.3/722.4, likely Dexron II/III. For 722.5/722.6, MB 236.10 or 236.14 (or equivalent) is essential. Manual will specify.
Coolant:
Mercedes-Benz Approved Antifreeze/Coolant (e.g., G05 or similar silicate-free formulation), mixed 50/50 with distilled water.
Brake Fluid:
DOT 4 Plus (or DOT 4) low-viscosity brake fluid.
Wiring Harness Degradation:
Cracking and failure of insulation on older wiring harnesses, particularly around the engine bay, due to heat and age. Requires inspection and potential replacement.
Convertible Top Hydraulics:
Leaking hydraulic cylinders, lines, and pump failure can lead to slow or non-functional top operation. Regular fluid checks and seal replacement are key.
Mass Air Flow Sensor Maf:
Failure of the MAF sensor can cause rough idling, poor acceleration, and fuel mixture issues, especially on M104 engines.
Interior Wood Trim:
Cracking or delamination of the burled walnut trim can occur due to age and UV exposure.
Window Regulator Motors:
Failure of power window regulators and motors, especially common in the earlier R129 models.
Distributor Cap And Rotor:
Wear and tear can lead to misfires and ignition problems on engines using distributor-based ignition systems.