Hitachi excavator accessory 4255055 tightening oil cylinder grease nozzle; Check valve

4255055 is a dedicated grease valve/grease fitting on the track adjuster cylinder in the Hitachi excavator track chassis system, which integrates a check valve structure internally. Main function: 1. Oil injection port: Inject butter into the high-pressure tensioning cylinder through a grease gun, push the piston rod to extend, and adjust the tension of the track. 2. Unidirectional check: prevents grease and pressure from flowing back into the oil cylinder, maintaining the set track tension. 3. Dustproof seal: effectively blocks soil, water, and impurities from entering the interior of the oil cylinder when closed. When the following situations occur, it is necessary to check or replace the grease nozzle: 1. Unable to inject oil or establish pressure during grease injection. 2. Leakage of oil and pressure from the grease nozzle, and inability to maintain track tension. 3. Blockage of the grease nozzle, ball valve jamming or thread damage. 4. Loose or too tight track, which cannot be stabilized after adjustment