COOLING GP 4626165 - Caterpillar

Use and Care of the 8T0452 Manometer
The 8T0452 Manometer can be used to measure the pressure of clean air and gases only. No liquid pressure media can be introduced into the manometer. To obtain accurate measurements, you must suspend the manometer in a vertical position. The manometer can not be used to measure pressures over 345 kPa (50 psi) or a vacuum greater than -67 kPa (-20 inHg). If the manometer is filled with water, it must be protected from freezing when temperatures are 0° C (32° F) or lower.The 8T0452 Manometer is equipped with a flexible steel metric scale and a sliding ZERO adjustment. The manometer can be filled with either mercury or distilled water. A bottle of Fluorescein green color concentrated wetting agent is included with the unit. The manometer cannot be used with .826 specific gravity red gauge oil. Mercury or distilled water are the only permissible measuring media.Filling
Use 0.946 L (1 quart) of distilled water, then add 22.2 mL (.75 oz) from a bottle of Dwyer A-126 Fluorescein green color concentrate. Remove a tubing connector from the manometer and pour the fluid in to mid-point level.Shake the manometer to remove any air bubbles. Slide the scale so the zero mark is in alignment with the meniscus of the two columns of fluid.For readings in centimeters of mercury, fill with 13.6 SP. Gr. triple distilled mercury. When the manometer is used with mercury, some discoloration of the vinyl tubing will normally occur.Reading
Connect the manometer to the source of pressure, vacuum or differential pressure. When pressure is imposed, add the number of centimeters that one column travels UP, to the amount the other column travels DOWN. This is the pressure reading. If a reading is desired in other units of measure, use the conversion chart.If one column should happen to travel further than the other column, due to minor variations in tube I.D. or to the pressure imposed, accuracy of the pressure reading thus obtained is not impaired.The U-tube manometer is a primary measuring device indicating pressure by the difference in the height of two columns of fluid. The fact that one column travels further than the other does not affect the accuracy of the reading.Both sides of the manometer must be at the same level and should read ZERO before pressure is measured. Pressure safety traps in the top of both manometer columns prevent the loss of fluid due to pressure surges, or pressures exceeding the pressure range of the instrument.If the fluid in one side of the manometer is higher than the fluid in the other side, the pressure safety trap is probably air locked. Applying slight air pressure on one of the manometer input ports will usually release the air lock. If it does not, slide a small wire or other similar instrument into the input fitting. Gently push down on the metal trap to release the air lock. Remove the wire or instrument that was used to push down on the trap.Cleaning
Cleaning