Subtopic: I.C. engine systems – fuel, cooling, lubrication, ignition, electrical, intake and exhaust
Question Statement:
In an open-center tractor hydraulic system, when all control valves are in neutral (no actuator being operated), the hydraulic fluid pumped by the pump:
Options:
(A) Passes freely through the open center of the valves back to the reservoir at low pressure
(B) Is blocked, causing system pressure to build up to the relief valve setting
(C) Is trapped inside the hydraulic cylinder to maintain lock
(D) Is diverted directly to the engine cooling circuit
Answer Key:
A
Step-by-Step Solution & Explanation
In an open-center circuit, the fixed-displacement pump delivers constant flow that circulates back to the sump at negligible pressure through the open center passage of the valve bank when all spools are centered.