The Engineman 3, NAVEDTRA 10539, introduced the two primary types of jacking gear, the ring gear, and the pinion assembly, and described their use. The only maintenance required for jacking gear is periodic inspection for wear and minor lubrication of the moving parts of the pinion assembly.

FUEL AND OIL PURIFIERS

Specific directions for operating a purifier are given in the manufacturers instructions provided with the unit. The following information is general and applies to both the fuel and the oil purifiers.

For maximum efficiency, purifiers should be operated at their maximum designed speed and rated capacity. An exception to operating a purifier at its designed rated capacity is when the unit is used as a separator with 9000 series detergent oil. Some engines using the 9000 series oils are exposed to large quantities of water. When the oil becomes contaminated with water, it has a tendency to emulsify. The tendency to emulsify is most pronounced when the oil is new and gradually decreases during the first 50 to 75 hours of engine operation. During this period, the purifier capacity should be reduced to approximately 80 percent of its rated capacity.

Most oils used in Navy installations can be heated to 180F without damage to the oils. Prolonged heating at higher temperatures is not recommended because such oils tend to oxidize at high temperatures. Oxidation results in rapid deterioration. In general, oil should be heated enough to produce a viscosity of approximately 90 seconds Saybolt universal (90 SSU), but the temperature should not exceed 180F. The following temperatures are recommended for purifying oils in the 9000 series:

Military Symbol Temperature (F)

9110 140

9170 160

9250 175

9500 180

Pressure should not be increased above normal to force a high viscosity oil through the purifier. Instead, the viscosity should be decreased by heating the oil. Pressure in excess of that normally used to force oil through the purifier will result in less efficient purification. On the other hand, a reduction in the pressure that forces the oil into the purifier will increase the length of time the oil is under the influence of centrifugal force and, therefore, will tend to improve results.