Automotive Workshop Tools, Equipment, and Materials
What this domain tests
Workshop tools and materials questions test identification, correct use, care and calibration of hand tools, measuring instruments, lifting equipment and consumables.
Core rules
- Micrometer least count is usually 0.01 mm; vernier caliper 0.02 mm; dial gauge 0.01 mm. Always check zero before measuring.
- A torque wrench is a setting tool, not a breaker bar; it must be calibrated and returned to its lowest setting after use.
- Sockets are six-point for high torque, twelve-point for accessibility; impact sockets are black and must not be used on hand ratchets.
- Feeler gauges measure valve clearances and gaps; plastigauge measures bearing oil clearance; a dial bore gauge measures cylinder wear.
- Lifting equipment - trolley jack, axle stands, engine crane, chains - must be rated for the load and inspected before use.
- Consumables include thread-locking compound, copper grease, gasket sealant, brake cleaner and correct-grade coolant.
Worked example
A micrometer shows 5.5 mm on the sleeve and 28 divisions on the thimble. Reading = 5.5 + (28 × 0.01) = 5.78 mm. If the zero check shows the thimble at 0.02 mm when closed, subtract that error: 5.78 − 0.02 = 5.76 mm. The reasoning is to read the main scale first, add the thimble fraction, then apply the zero error.
Traps that cost marks
Reading the thimble in the wrong direction, ignoring zero error, using an adjustable wrench on hex fasteners, using a chrome socket with an impact gun, and relying on a torque wrench that has been dropped.