The minimum lubrication oil pump  is a resistance-type lubrication system. The system pumps an air and oil mixture through a nylon tube to the spindle.
Minimum Lubrication - Oil Pump - CALM - Identification
The drip sight glass lets you see the quantity of oil that goes to the spindle.
note: The first drip sight glass was installed on Haas machines with the Grease-Gun Axis Lubrication System made after April 2010.
- The strainer basket filters the oil.
The level switch tells you if the oil level is low. This causes Alarm 121 Low Lube or Low Pressure.
note: Oil reservoirs made before November 2013 have a low-level switch.note: Oil reservoirs made after November 2013 have a level sensor.
- The oil pump pushes oil through the system.
Minimum Lubrication - Oil Pump - Spindle Lubrication System - Spindle Lubrication
A nylon tube supplies the spindle with an air/oil mixture through a non-restrictor fitting.
A mixture of air and oil from the oil reservoir lubricates the spindle.
- Every 30 minutes, when the spindle is in motion, the oil pump inside the oil reservoir  sends the air and oil mixture through a nylon tube  to the spindle.
- This system uses SHC 625. The oil reservoir stores the oil.