(l)
If the IDG is empty (indicating the overtemperature relief valve has opened), replace the IDG (AMM 24-11-01/401).
S 216-012
(2) Examine the color and the condition of the oil -Visual
NOTE:____Some types of IDG oils are colored black. A visual inspection of the oil cannot detect if the oil has been overheated or mixed with other types of fluids.
(a)
Remove a sample of oil from the IDG in a glass bottle.
(b)
Examine the oil for unusual color caused by contamination, sludge, coke, high temperature, or incorrect mixtures of oil. 1) If the IDG oil is contaminated (with Skydrol, water,
chlorine, or other contaminates), clean the oil system as follows: a) Do this task: "Change the Integrated Drive Generator
Oil" (AMM 12-22-07/301).
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b) Start the applicable engine (AMM 71-00-00/201). c) Operate the engine until the IDG oil temperature
reaches 175 degrees F. d) Stop the engine (AMM 71-00-00/201). e) Do this task: "Change the Integrated Drive Generator
Oil" (AMM 12-22-07/301). f) Make sure that the scavenge filter appears clean.
S 416-009
(3)
Close the left thrust reverser half (AMM 78-31-00/201).
S 756-036
(4)
Examine the IDG oil - Hydrometer
(a)
Get an oil sample from the IDG.
(b)
Use a hydrometer to find the specific gravity of the IDG oil sample.
(c)
Check the specific gravity of new IDG oil.
NOTE: The specific gravity of new oil is from 0.89 to 0.99.
____
NOTE: The specific gravity of Mobil Jet II is 1.0035.
____
(d) Compare the specific gravity readings.
1) Do the following if the specific gravity reading is lower than the specific gravity of the new IDG oil. a) Replace the fuel/oil cooler (AMM 79-21-01/401). b) Replace the IDG oil (AMM 12-22-07/301). c) Change the scavenge filter (AMM 24-11-04/401). d) Run the engine until the IDG oil temperature is 175
degrees F. e) Drain the oil. f) Change the scavenge filter (AMM 24-11-04/401). g) Replace the IDG oil (AMM 12-22-07/301).
2) Do the following if the specific gravity is more than the specific gravity of the new IDG oil.
NOTE:____Mobil Jet II has a specific gravity of 1.0035. The specific gravity of turbine oil and water would not exceed 1.000. Do the alcohol test if you suspect water in the oil.
a) FOR IDG USING OIL WHICH ARE CLEAR; Get an IDG oil sample.
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b) Use a new unopened container of methyl alcohol for this test. Methyl alcohol absorbs water from the air. Incorrect test results will occur when methyl alcohol has absorbed water from the air.
c) Put one part of oil and three parts of methyl alcohol into a container.
NOTE:____ The test results will not be affected if the oil and alcohol mixture is mixed by weight or volume.
d) e) f) g) h) i) j) k) l) Shake the alcohol and oil sample for one minute.If the sample turns cloudy the water content in the IDG oil is too high. Flush the IDG and the IDG cooling system with oil (AMM 12-22-07/301).Replace the scavenge filter (AMM 24-11-04/401).Run the engine until the IDG oil temperature reaches 175 degrees F.Drain the oil.Replace the scavenge filter (AMM 24-11-04/401).Service the IDG (AMM 12-22-07/301).FOR IDG USING OILS WHICH ARE COLORED BLACK; Get an IDG oil sample.Use a new unopened container of ethyl alcohol for this test. Ethyl alcohol absorbs water from the air. Incorrect test results will occur when ethyl alcohol has absorbed water from the air.
m) Put one part of oil and three parts of ethyl alcohol into a container.
NOTE:____ The test results will not be affected if the oil and alcohol mixture is mixed by weight or volume.
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