The relief valve protects the oil pump and lube oil system from what condition?

• A. Excessive Pressure
• B. Low Pressure
• C. Contamination
• D. Overheating

Answer: (A)

The main idea here is that the relief valve acts as a safety valve to keep the oil system from experiencing too high pressure. When the system pressure reaches its set limit, the relief valve opens and allows excess oil to bypass back to the pump inlet or sump. This prevents damage to the oil pump, bearings, seals, and passages from pressure spikes, maintaining a safe, steady lubrication supply.

Low pressure is controlled by different protections such as alarms or other pump/fuel-flow controls, while contamination and overheating are addressed by filtration and cooling systems, not by the relief valve.