Maintenance, Lubrication, Fuels and Fluids
What the exam tests
Maintenance, Lubrication, Fuels and Fluids tests scheduled servicing, correct fluids, contamination control and safe maintenance practice. The exam expects you to use the manufacturer's specification, not guesswork.
Core rules
- Follow the maintenance schedule by hours or calendar time, whichever comes first. Record greasing, filter changes, oil sampling and adjustments.
- Use the specified diesel, engine oil, hydraulic oil, coolant and grease. Wrong fluid can damage seals, reduce lubrication or cause overheating.
- Keep containers clean and labelled. Clean around filler caps before opening. Prevent dirt and water from entering hydraulic or fuel systems.
- Before maintenance, isolate the machine, lower attachments, release stored pressure and let hot parts cool. Use lockout/tagout where required.
- Manage waste oil, filters and batteries as controlled waste. Do not pour fluids onto the ground or into drains.
Worked example
A telehandler needs hydraulic oil. The manual specifies an ISO VG 46 hydraulic oil, but only ISO VG 68 is available. The operator must not top up with the wrong grade. A thicker oil can change flow and response, especially in cold conditions, and may overheat the system. The correct action is to obtain the specified oil and record the top-up.
Traps
Do not open a hot radiator cap. Do not use petrol or mixed fuel in a diesel engine. Do not ignore a fuel water separator warning. Do not mix oils to reach a level.
Key points
- Follow the manufacturer's fluid specification.
- Keep dirt and water out of fuel and hydraulics.
- Isolate and cool before maintenance.
- Dispose of waste fluids correctly.