Agric Equipment Mechanic flashcards
Agric Equipment Mechanic · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- ROPS
- Rollover protective structure that resists crushing in a rollover; it only protects the operator when used together with a fastened seat belt.
- PTO master shield
- Guard covering the tractor PTO stub shaft; it must be in place to prevent entanglement and works with the driveline and implement shields.
- Hydraulic injection injury
- Pressurized fluid forced through skin creates a surgical emergency; immediate medical treatment is required even if the wound looks minor.
- Compression ignition
- Diesel ignition by heat of compression rather than a spark; requires high compression ratio to raise air temperature above fuel ignition point.
- Common rail system
- Fuel system where a high-pressure pump charges a shared rail; the ECU controls injector timing and duration independently of rail pressure generation.
- Black exhaust smoke
- Dark smoke from incomplete combustion, typically caused by over-fueling, restricted intake air, or excessive load on the engine.
- Gear ratio
- Ratio of driven gear teeth to driving gear teeth; overall train ratio is the product of each individual stage ratio.
- Powershift transmission
- Transmission using hydraulically applied wet clutches to shift under load without interrupting power; a single gear loss points to that clutch pack.
- Differential
- Gear set allowing drive wheels to rotate at different speeds during turns; a locked differential causes tire scrub and driveline windup.
- Hydraulic horsepower
- Power delivered by hydraulic flow, calculated as pressure in psi times flow in gallons per minute, divided by 1714.
- Relief valve
- Valve that limits maximum system pressure by bypassing flow; opening early causes weak operation across all hydraulic circuits.
- Pump cavitation
- Formation and collapse of vapor bubbles from restricted inlet flow or air leaks, producing noise, aeration, and pump damage.
- Voltage drop test
- Measuring voltage lost across a circuit under load; excessive drop locates high-resistance connections, cables, or grounds.
- Series battery connection
- Wiring batteries positive to negative adds their voltages while amp-hour capacity stays the same as a single battery.
- CAN bus termination
- End-of-bus resistors, typically 120 ohms each, provide about 60 ohms across the data lines measured with power off on a healthy bus.
- Hydrostatic steering
- Steering using an orbitrol valve and hydraulic pressure; loss of assist with the engine off points to charge pressure problems.
- Brake fade to floor
- Pedal sinking under steady pressure indicates internal master cylinder bypass or a fluid leak, not normal pad wear.
- Caster angle
- Steering axis tilt that provides straight-line stability; too little causes wander and too much increases steering effort.
- Tire load-inflation table
- Chart giving maximum load per tire at each inflation pressure; running below the rating for the axle load causes heat and failure.
- Track tension
- Sag measured at a specified point per manufacturer; too loose causes derailment and too tight accelerates wear.
- Wheel nut torque pattern
- Tightening lug nuts in a star sequence with a calibrated wrench, then retorquing after initial operation to ensure even clamp load.
- Superheat
- Evaporator outlet temperature minus evaporator saturation temperature; too low risks liquid refrigerant reaching and damaging the compressor.
- Subcooling
- Condenser saturation temperature minus condenser outlet temperature; low subcooling typically indicates an undercharged refrigerant system.
- Refrigerant recovery
- Removing and storing refrigerant instead of venting it; the system must be evacuated before charging to remove moisture and air.
- RTK accuracy
- Real-time kinematic GPS correction giving roughly one-inch pass-to-pass accuracy, used for controlled traffic and high-precision operations.
- Section control
- Automatic switching of boom or seeding sections based on GPS position to reduce overlap and skips in the field.
- ISOBUS
- Standard allowing displays and implements from different manufacturers to communicate; faults often trace to bus termination or address conflicts.
- Five-step diagnosis
- Structured troubleshooting: verify complaint, gather information, inspect, test, then repair and confirm, avoiding unnecessary parts replacement.
- Torque-to-yield bolt
- Fastener tightened past its elastic limit for clamp load; it is single-use and must not be reused during repair.
- Fluid analysis trend
- Tracking wear metals and contamination across successive oil or hydraulic samples; a single sample is far less informative than a trend.
- Pressure versus flow test
- Separate hydraulic checks; a system can show correct pressure yet deliver inadequate flow under load, so both must be verified.
- Valve lash
- Clearance between rocker and valve stem set to spec hot or cold; incorrect lash alters effective compression and valve timing.