Fluid is dripping from nozzles

A small amount of fluid dripping from a Coolubricator™ nozzle immediately after the system has been shut off is normal, especially when the nozzle is oriented downward. If the nozzle continues to drip or drains excessively, check the following:

• Coaxial tubing and capillary
  • Unist systems commonly use coaxial tubing, with a small inner capillary carrying fluid inside a larger hose carrying air.
  • The fluid should remain in the capillary when it is intact and properly sealed to the pump outlet barb.
  • Cuts, tears, abrasions, or a poor seal at the pump barb can allow fluid to drain from the capillary and drip from the nozzle.
• Capillary handling
  • Damage commonly occurs when coaxial tubing is disconnected, reconnected, shortened, or otherwise handled.
  • Take care not to nick or damage the capillary.
  • When reinstalling the capillary onto the pump barb, trim off the section that was previously installed to provide a clean, undamaged section for the new connection.
  • Never use a blade to cut lengthwise along the capillary to remove it from the pump barb. This can damage the brass barb and prevent a proper seal.
  • Avoid using pliers carelessly to pull the capillary from the barb, as this can also damage the fitting.
• Pump outlet check seal
  • If the capillary and pump barb connection are in good condition, a compromised pump outlet check seal may be the cause.
  • Possible causes include:
    • Dirt or debris on the check seal
    • A damaged check seal
    • Damage to the sealing surface
  • These conditions require a complete pump rebuild. Contact Unist Technical Support for assistance.
• Excessive fluid supply pressure
  • The pump can be supplied with 5–10 psi of pressurized fluid.
  • Excessive inlet pressure can force the outlet check seal open and allow fluid to flow through the pump while it is not running.

Helpful tips for working with coaxial tubing can be found in the related video.