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The # XXXXX check valve needs to be loosened , this will allow the cylinder to move in and make the tracks slack enough to remove. You can get the cylinder to move in by driving up on block, until it is in the center, loosening the track.. Tighten the # XXXXX screw so it will keep cylinder closed, drive off block and track should be loose enough to remove. Use the bucket to raise front end and use jack under rear to get track in air.