Single Acting Telescopic Dump Cylinder

WARNING: Before working on a single acting telescopic dump cylinder mounted on a truck or trailer unit, use supports or holding devices that will absolutely prevent the body from accidentally lowering. Place control valve in the “LOWER” position to assure that all pressure has been relieved from the cylinder.

Single Acting Telescopic Dump Cylinder Recommendations

  • A single acting telescopic dump cylinder is not to be used as a stabilizer on a dump body or dump trailer. The cylinder is strictly a lifting device and is not a structural member of the dumping unit.
  • The single acting telescopic dump cylinder should float in the pin mountings. It should be installed with 1/8″ to 3/16″ of clearance between the pin and the pin hole if the mounting eye is wider than 5″, or with 1/16″ to 1/8″ clearance if the mounting eye is less than 5″ wide. There should be a clearance of 1/4″ per side on eyes less than 5″ to 1/2″ clearance per side on eyes in excess of 5″ wide. This is to allow the body to sway slightly while dumping, without putting a side load on the cylinder. The cylinder end mounts should be lubricated regularly.
  • Cylinders cannot withstand side pressures from a dump unit leaning. A tractor trailer unit must be in a straight line when dumping, not jackknifed. All dump units must be on firm, level ground and not operated during heavy crosswinds. Failure to do so may cause the unit to upset.
  • Do not overload the dump! unit. The load must be evenly distributed during loading and unloading.
  • Do not jerk or slingshot dump unit in an attempt to free a sticking or frozen load. Pulling forward (or backing up) and hitting the brakes or lowering the body part way and then quickly engaging the valve in the “HOLD” or “RAISE” position will cause a tremendous pressure spike. This pressure spike may bulge or split one of the larger stages of the cylinder.
  • When lowering a load that is sticking, the dump unit must be feathered down slowly to avoid a high pressure build up in the cylinder.
  • Do not operate cylinder at pressures above factory recommended operating pressures (Normally 2,000 P.S.I. unless otherwise approved).
  • The driver should stay at the controls during the entire dumping operation. If the body starts to lean to one side, the driver should immediately lower the body. It is important to feather the control valve into the hold position to avoid a pressure spike in the cylinder.
  • Do not operate cylinder with personnel or equipment alongside. The dump unit must be lowered completely before moving unit.
  • Do not drive with P.T.O. or Hydraulic Pump engaged.
  • Hydraulic hoses should be inspected regularly and replaced if worn out or damaged.
  • Hydraulic oil should be inspected or changed regularly and whenever anew cylinder is installed.
  • A damp to light film of oil on each plunger or stage of a telescopic cylinder indicates good cylinder operation.
  • After many cycles of the cylinder, a small accumulation of oil may be noticed on the plungers or sleeves at the head nuts. This should not be mistaken for packing leakage.
  • Cylinder should be free of entrapped air. It is advisable to bleed air from cylinder weekly for a smooth operation.