(b) Pump. Remove top plate and fill with special vacuum-pump oil until it is slightly above oil level as
indicates in window on side of pump. In operation, the oil should be even with or slightly above the oil level. If
insufficient oil is used, a good seal around the vanes will not be maintained. If too much oil is used, oil may back through
the pump trap into the vacuum line. Whenever oil in pump is changed, pump must run for some time or a closed system
before lowest pressure is obtained. Check to make sure that electric wiring is tight, check mounting bolts for tightness,
and check drive belt periodically to make certain that it is not too tight or too loose. Belt should be just tight enough to
prevent slippage when pump is operating.
2-16. STORAGE CABINETS.
a. Component Part. The storage cabinets (Units No. 9 thru 14, 24, and 26) contain much of the glassware, metal
equipment, porcelain ware, tubing, stoppers, etc., which are component parts of the testing apparatus or which are used
in testing procedures.
b. Operation. For detailed directions on assembling specific types of testing apparatus, and for information on
testing procedures, refer to test methods in the appropriate test references.
2-17. CHEMICAL STORAGE CABINET.
The chemical storage cabinet (Unit No. 15) contains many of the chemicals and some miscellaneous equipment
necessary for the testing of petroleum products.
2-18. BALANCE TABLE CABINET.
a. Component Parts. The balance table cabinet (fig. 2-19) contains the analytical balances, complete U with
weights; torsion balance, complete with weights; and foam test apparatus, consisting of cylinder, glass tube with diffusion
stone, flowmeter, constant temperature bath with heating elements, thermoregulator and control box.
(1) Balances. Remove balances and cases from within cabinet; remove component parts from drawer, and
assemble on top of cabinet. Adjust balances and level.
(2) Foam Test Apparatus. Remove component parts of foam test apparatus from cabinet, and assemble on
top of cabinet. For complete directions on assembling apparatus and for detailed procedure for testing foaming
characteristics of crankcase oils, refer to testing methods in appropriate testing references.
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