On diesel engines, if cooling water discharge is not adequate, which two components should be checked for obstructions and adjusted for correct flow?

• A. Strainer; Pressure reducing valve
• B. Filter; Temperature sensor
• C. Strainer; Relief valve
• D. Strainer; Gauge

Answer: (A)

When a diesel engine’s cooling water discharge is inadequate, focus on components that directly regulate or obstruct flow. The strainer sits in the path to catch debris; if it’s clogged, it creates a bottleneck and limits how much water can pass, lowering the discharge. Cleaning or replacing the strainer removes that blockage and restores flow.

The pressure reducing valve also directly controls how much water is allowed through. If it’s not opening fully, stuck, or not set correctly, it will cap the flow to the cooling circuit regardless of other conditions. Inspecting and adjusting the valve to the correct setpoint restores proper discharge.

Other items listed don’t adjust flow in the discharge path as directly. Filters are similar to strainers but may be located elsewhere, temperature sensors monitor conditions without changing flow, relief valves protect against overpressure, and gauges measure rather than regulate flow.