TM 10-3930-669-20 7.  LIFT CYLINDER(S) DOES NOT OPERATE (CONT). KNOWN INFO TEST OPTIONS Side shift cylinder operates. Lift cylinder hoses OK. Pressure test. STE/ICE-R #51. POSSIBLE PROBLEMS REASON FOR QUESTION Stack valve faulty. Secondary flow regulator faulty. Mast assembly faulty. Lift cylinder faulty. It     stack     valve     is     faulty,     lift cylinders will not operate. KNOWN INFO TEST OPTIONS Side shift cylinder operates. Lift cylinder hoses OK. Stack valve OK. Pressure test. STE/ICE-R #51. POSSIBLE PROBLEMS REASON FOR QUESTION Secondary flow regulator faulty. Mast assembly faulty. Lift cylinder faulty. If     stack     valve     is     faulty,     lift cylinders will not operate. ¬ ¬ 2-464