This spring insert sits in the engine assembly, where it applies a controlled preload to a valve or plunger mechanism. It maintains consistent contact force between the moving parts, which is necessary for correct timing and sealing within the system. If the insert loses its spring rate or collapses, the affected valve may not close fully, leading to a loss of compression or erratic engine operation. The original AGCO-manufactured part is formed to the same free length and load-deflection curve as the factory component, so it restores the original spring force without requiring shimming or adjustment. On installation, verify that the insert seats fully in its bore and that the retaining cap or keeper is secured to the specified torque.