RRB ALP Mechanic Motor Vehicle Syllabus

The RRB ALP CBT 2 Part B - Mechanic Motor Vehicle trade syllabus covers the core technical knowledge tested in the 75-question, 60-minute trade-specific section of the RRB ALP 2027 examination. Part B is qualifying in nature only: candidates must score a minimum of 35% (26.25 marks out of 75) to clear Part B. The marks scored in Part B are NOT added to the final merit list. Merit is determined entirely by CBT 2 Part A scores. The syllabus for Part B is based on the NCVT (National Council for Vocational Training) ITI curriculum for the Mechanic Motor Vehicle trade at the ITI certificate level.

Quick Facts: ALP Mechanic Motor Vehicle Trade

Important Note on Part B

CBT 2 Part B is qualifying only. A candidate who scores below 35% in Part B is eliminated regardless of their Part A score. However, a candidate who clears the 35% threshold in Part B is ranked exclusively on their CBT 2 Part A score. This makes Part B preparation essential for elimination prevention, while Part A preparation determines the final rank. Candidates should ensure they are thoroughly familiar with the Mechanic Motor Vehicle trade theory and practical knowledge at the ITI level before the examination.

Detailed Mechanic Motor Vehicle Trade Syllabus (Part B)

The Mechanic Motor Vehicle trade syllabus for RRB ALP CBT 2 Part B is drawn from the NCVT ITI curriculum and tests trade theory, applied knowledge, and practical understanding across the following topic areas:

1. Internal Combustion Engines

•        Engine Classification: 2-stroke and 4-stroke; petrol and diesel; naturally aspirated and turbocharged; DOHC and SOHC; water-cooled and air-cooled; inline, V, W, opposed, radial

•        4-Stroke Petrol Engine: construction; working cycle (suction, compression, power, exhaust); valve timing diagram; valve timing events; firing order (4-cylinder: 1-3-4-2 or 1-2-4-3)

•        4-Stroke Diesel Engine: construction; working cycle; compression ratio (14:1 to 22:1); injection; differences from petrol engine

•        2-Stroke Engine: construction; working; crankcase compression; ports (inlet, transfer, exhaust); applications; disadvantages

•        Engine Components: cylinder block; cylinder head; piston; piston rings; gudgeon pin; connecting rod; crankshaft; flywheel; camshaft; valve train (OHV, OHC, DOHC); engine bearings

•        Engine Performance: IMEP; BMEP; BHP; BSFC; volumetric efficiency; mechanical efficiency; thermal efficiency; power curves; torque curve

•        Engine Cooling System: necessity; thermostat; water pump; radiator; coolant (ethylene glycol mixture); expansion tank; pressure cap; fan (mechanical and electric); cooling system testing and maintenance

•        Engine Lubrication System: necessity; wet and dry sump; oil pump types; oil pressure relief valve; oil filter (full-flow and bypass); oil cooler; SAE viscosity grades; multigrade oils; oil change intervals; oil pressure testing

•        Valve Timing and Adjustment: valve clearance (hot and cold); feeler gauge; adjustment sequence; OHV and OHC adjustment procedures; valve bounce; valve float

•        Engine Diagnostics: compression test; cylinder leakage test; vacuum test; oil pressure test; engine noise diagnosis (top end noise, bottom end noise, valve noise)

2. Fuel Systems

•        Petrol Fuel System: fuel tank; fuel pump (mechanical and electric); fuel filter; carburettor (float circuit; main metering; idle; power; accelerator pump; choke); multi-point fuel injection (MPFI) -- injectors; fuel rail; fuel pressure regulator; ECU; sensors (MAF, MAP, TPS, O2)

•        Diesel Fuel System: fuel tank; lift pump; primary filter; secondary filter (water separator); injection pump (inline, rotary DPA, VE); injectors (hole-type; pintle-type; pencil type); bleeding procedure; common rail direct injection (CRDI) -- rail; high-pressure pump; solenoid injectors; pressure regulator; ECU control

•        Alternative Fuels: CNG (cylinder; regulator; sequential injection; mixer; ECU); LPG (storage; vaporiser; mixer; safety cut-off); biodiesel; ethanol blends (E10, E20); hydrogen -- safety provisions

•        Emission Control: EGR; catalytic converter (three-way catalyst for petrol); diesel oxidation catalyst (DOC); diesel particulate filter (DPF); SCR with AdBlue; EVAP system; OBD-II fault codes; Bharat Stage VI (BS6) requirements

3. Power Transmission

•        Clutch: single plate; diaphragm spring; multi-plate; cone; centrifugal; hydraulic; clutch pedal free play; clutch cable/hydraulic adjustment; clutch faults (slip, drag, judder, noise)

•        Gearbox: sliding mesh; constant mesh; synchromesh; epicyclic (automatic -- torque converter, planetary gear set); CVT; AMT; DCT; gear ratios; gear selection; gearbox faults (jumping out, hard shifting, noise, oil leaks)

•        Propeller Shaft: universal joints (Hooke, CV); slip joint; propeller shaft balancing; vibration diagnosis

•        Final Drive and Differential: hypoid bevel gears; ring and pinion; differential action; limited-slip differential; final drive ratio; axle types (semi-floating, three-quarter floating, fully floating); pinion bearing preload setting

•        Four-Wheel Drive (4WD): transfer case; high and low range; free-wheeling hub; electronic 4WD; AWD systems

4. Chassis, Suspension and Steering

•        Frame and Body: chassis types (ladder, backbone, monocoque/unibody); body-on-frame vs unibody; structural repair basics

•        Front Suspension: independent (MacPherson strut, double wishbone, multi-link); rigid axle; springs (coil, torsion bar); shock absorbers (telescopic damper -- monotube, twin-tube); anti-roll bar

•        Rear Suspension: live axle with leaf springs; independent (trailing arm, multi-link, semi-trailing arm); subframe

•        Wheel Alignment: camber; caster; king-pin inclination; toe-in and toe-out; Ackermann principle; alignment procedure; four-wheel alignment; effects of misalignment on tyre wear and handling

•        Steering Systems: manual (rack and pinion, recirculating ball); hydraulic power steering (PAS) -- pump, hoses, steering gear; electric power steering (EPS); play in steering; hard steering; pull to one side -- diagnosis

•        Tyres and Wheels: tyre construction (radial, bias-ply); tyre size designation (e.g., 205/55 R16 91V); inflation pressure; tyre wear patterns (under-inflation, over-inflation, camber wear, toe wear); rotation; balancing; rim types

5. Braking Systems

•        Hydraulic Brake System: master cylinder (single and tandem); brake fluid (DOT 3, DOT 4, DOT 5.1 -- properties, boiling point, hygroscopicity); wheel cylinders; calipers (sliding, fixed); lines and hoses; bleeding procedure

•        Drum Brakes: construction; leading and trailing shoes; self-energising; duo-servo; wheel cylinder; brake shoe adjustment; brake drum inspection

•        Disc Brakes: construction; floating and fixed calipers; ventilated and cross-drilled discs; brake pads (friction material; wear indicator); rotor minimum thickness; brake judder causes

•        Vacuum Servo (Brake Booster): working principle; vacuum source (engine manifold or pump); one-way valve; testing

•        ABS: wheel speed sensors; HCU; ECU; pressure modulation cycle (pressure build, hold, reduce); EBD; BA; ESP/ESC (stability control); system testing; wheel speed sensor diagnosis

•        Parking Brake: types (drum-in-hat, rear calliper EPB); adjustment; inspection; MOT equivalent standards

•        Air Brakes (Heavy Vehicles): compressor; air dryer; reservoir; brake valve (foot valve); quick release valve; relay valve; spring brake (emergency); slack adjuster; brake chamber -- system testing

6. Automotive Electrical and Electronics

•        Battery: construction; CCA; Ah rating; state of charge; hydrometer; open circuit voltage; load test; charging (constant current, constant voltage, opportunity charging); AGM and EFB batteries for start-stop systems

•        Starting System: starter motor (reduction gear, planetary gear); engagement (Bendix, pre-engaged); starter relay; neutral safety switch; starter circuit testing

•        Charging System: alternator (stator, rotor, diode pack, voltage regulator); charging voltage (13.8-14.7 V); belt tension; alternator output test; charging circuit diagnosis

•        Ignition System: conventional (contact point); electronic (Hall effect, optical); distributorless (DIS, COP); spark plug (heat range, gap, electrode wear, fouling diagnosis); ignition timing; knock sensor; misfire diagnosis

•        Lighting System: headlight types (halogen, HID, LED, matrix LED); DRL; indicator; horn; wiper motor and intermittent wiper; heated rear screen; Park Distance Control (PDC)

•        Engine Management System (EMS): ECU; sensors (CKP, CMP, MAF, MAP, O2 (lambda), IAT, ECT, TPS, knock); actuators (injectors, IACV, EVAP solenoid, EGR solenoid); OBD-II connector; scan tool; DTC reading and clearing; live data monitoring

•        CAN Bus: principle; high and low speed CAN; bus topology; message identifier; arbitration; gateway ECU; diagnosis with oscilloscope and scan tool

•        ADAS Basics: adaptive cruise control; lane keeping assist; AEB; parking sensors; 360-degree camera system; radar and camera calibration requirements after repair

7. Vehicle Inspection, Servicing and Safety

•        Scheduled Maintenance: service intervals; items checked and replaced (oil, filters, spark plugs, coolant, brake fluid, belts, tyres); job card preparation

•        Pre-Delivery Inspection (PDI): checklist for new vehicle; fluid levels; tyre pressure; lights; wipers; customer handover

•        Fitness Certificate and PUC: statutory requirements; smoke test (diesel -- smoke meter); CO and HC test (petrol -- CO-HC analyser); road worthiness inspection

•        Workshop Safety: hydraulic jack and axle stand use; ramp safety; exhaust extraction; chemical safety (brake cleaner, WD40, battery acid); fire safety; PPE

•        Environmental Regulations: used oil disposal; coolant disposal; end-of-life tyre management; battery disposal; CFC refrigerant regulations for automotive AC

Weightage Analysis and Preparation Strategy

The 75 Part B questions are drawn proportionally from across all major topic areas of the Mechanic Motor Vehicle trade curriculum. Questions test both theoretical knowledge (principles, formulae, definitions, standards, safety rules) and applied understanding (fault diagnosis, calculations, material selection, tool usage, quality checks). The following approach maximises Part B preparation efficiency:

•        Revise systematically from NCVT ITI Mechanic Motor Vehicle trade theory textbooks for Semester 1 and Semester 2

•        Focus on definitions, formulae, standards (BIS/IS codes), safety regulations, and technical specifications -- these are directly testable as MCQs

•        Practise numerical calculations relevant to the trade (e.g., circuit calculations for Electrician, speed/feed calculations for Fitter/Turner/Machinist)

•        Study common faults, their causes, symptoms, and remedies for all major equipment in the trade

•        Revise tools, instruments, and equipment used in the trade: their names, specifications, uses, and maintenance

•        Solve previous years' RRB ALP Part B question banks for your specific trade

•        Allocate 60 minutes of daily trade-specific study alongside Part A preparation throughout the preparation period

Frequently Asked Questions

Q1. Is CBT 2 Part B merit-based or qualifying?

CBT 2 Part B is qualifying only. A minimum score of 35% is required to pass Part B. The marks scored in Part B are not added to the merit list. Only Part A marks determine the final ranking.

Q2. What happens if a candidate fails Part B?

Candidates who score below 35% in Part B are disqualified regardless of their Part A performance. They will not be considered for Document Verification or further selection stages.

Q3. How should I divide study time between Part A and Part B?

Since Part A determines the final merit and Part B is qualifying, prioritise Part A in your preparation. However, allocate at least 30 to 40% of study time to Part B to ensure you comfortably clear the 35% qualifying threshold. Aiming for 50 to 55 marks (about 70%) in Part B provides a safe buffer.

Q4. Is the Part B syllabus the same as the ITI exam syllabus?

Yes. The RRB ALP Part B syllabus is directly based on the NCVT ITI curriculum for the relevant trade. Candidates who have completed their ITI in the relevant trade and revised their course material systematically are well positioned for Part B.