Lubricators

The advantages if any of a hydrostatic lubricator is that the oil is atomized with the steam at the lubricator and carried to the valves with the steam. . This is helpful in that the oil is
Distributed with the steam at the valves & cylinders. The disadvantage of a hydrostatic, particularly in mountain railroading, is that when the locomotive is running, gravity is about the only factor moving the oil down line as the lubricator and the valves & cylinders operate at similar pressures. When an engine is using compression to come off a steep grade as talked about previously, the cylinder and valve pressures can be much higher than the boiler pressure rendering the hydrostatic lubricator useless.
A mechanical lubricator has many small oil pumps all building oil pressure for their targeted valve or cylinder. Then at the valve or cylinder or air pump there is what is called a terminal check valve. This check valve can be adjusted to allow the oil pressure to build to a wanted pressure before opening and giving a squirt of oil to the valve or cylinder. At the C&TS I always set them at 350 to 375lbs. This makes for a very positive oil flow. But if the valve & cylinder have cold air in them the oil will tend to puddle in the bottom of everything and not distributed properly. Both can be connected to valves and cylinders but they aren’t always connected to both.
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