Hard Time

File: 082696_d50030_057.txt
Page: 057
Total Pages: 101
C.  Questions on Greases


1.  What grease should be used in ground vehicles/equipment?

    Answer:  The recently upgraded MIL-G-0010924E(ME) or MIL-G-~O924F Grease
             Automotive and Artillery (GAA) should be used as they   possess a
             significantly higher operating temperature capability than the
             previous MIL-G-10924D Amd 2 version.   If at all possible, the
             MIL-C-L0924D Aind 2 GAA should not be used unless there is no
             other option available since its somewhat lower Dropping Point
             may cause oil leakage problems in those applications which
             themselves generate high operating temperatures.   If the pre-
             ferred MIL-G-O010924E (ME) or MIL-G-i0924F grease is una-
             vailable, use of MIL-G-83122 Grease Aircraft, General Purpose,
             Wide Temperature Range (WTR) is strongly recommended.


D.  Questions on Antifreeze/Coolants


1.  Will increasing the ratio of antifreeze (NIL-A-46153) to water improve
the heat transfer qualities of the antifreeze-water mixture?

    Answer:  No.   Decreasing the amount of water will actually lower ~he
             heat transfer properties.   For optimum performance, use
             of a 50:50 mixture of MILrA-46153 and water is recommended.

2.  Can locally obtained water be used in cooling systems of engines?

    Answer:  &o. If at all possible, use either distilled water or potable
             water when preparing antifreeze-water mixtures.  Local water in
             Saudi Arabia is highly saline (i.e., has a high mineral con-
             tent) and will calcify in cooling system~ which in turn will
             si0~nificant1y reduce the cooling capacity.

3.  Can commercial antifreeze be used in lieu of ~IL-A-46i53?

    Answer:  No.   MIL-A-46153 is a "formulation-type" ~pecification whereas
             essentially all commercial antifreeze use "performance-type"
             specifications.   Using MIL-A-46~53 admixed with commercial
             anti freeze will produce incompatibility problems leading to
             increased cooling system maintenance problems or possibly
             failures.


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