Oil sight glasses by PK Machine clearly reveal changes in machinery lubricant quality to help analyze oil condition.


Machined to precise specifications with optical grade clear acrylic and friction bonded, these 1 ounce water finders have a brass drain valve ¼” NPT.

Each oil sight glass is manufactured from solid material for strength, durability and quality fitting.

They are easy to install directly to the drain port located at the bottom of a reservoir. There are several sizes and valve options.

  • Optical Grade Acrylic
  • Machined USA materials
  • Brass Drain Valve ¼” NPT
  • 145- Brass Drain Cock
  • 1300 Aircraft grade Curtis Valve with ¼” spiral lock
  • 1600 Aircraft grade Curtis Valve with ¼” push lock
  • Temperature:
  • Maximum operating temperature 200 degrees F

  • Pressure:
  • 300 psi (tested to over 350 psi)

  • Chemical Compatibility:
  • Gear oil, mineral oil and synthetic oil
  • Chemical and Corrosion resistant

  • Dimensions:
  • Volume: 1 ounce
  • Overall Length: 2 3/8”
  • Outside Diameter: 1¾”
  • Applications:
  • Pumps
  • Gear Boxes
  • Turbines
  • Storage Tanks
  • Motors
  • Any oil lubricated sump or reservoir
  • The chart below describes the different size and valve options.
    If you are interested in buying a higher quantity, please see our distribution options or contact us directly 530-878-4855.

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