S 032-218

 (9)  
Disconnect the raceway drain fitting from the drain line just below the raceway.

 (a) Install a cap or plug into the raceway drain fitting.
 F. Forward Midspar Leak Check S1 - Inboard (Figs. 203 and 204)
 S 942-219
 (1)  
Put an empty container below the strut forward drain outlet
 (NSTA 154).

 S 792-220

 (2)  
With a funnel and hose, apply water over the top surface of the midspar, through access door 462EL/472EL at NSTA 217 as follows:

 (a)  Apply 254 to 258 fluid ounces (7510 to 7630 ml) of water in 3.5 to 4.5 minutes.
 NOTE: This is approximately 64 fluid ounces (1/2 gallon or
____ 1900 ml) per minute for 4 minutes.
 (b)  Make sure you completely wet the midspar upper surface and all the system penetrations into the midspar forward cavity.
 S 792-221
 (3)  Look for leaks as follows:
 (a)  
Make sure you see no water leaks at the midspar lower surface.

 (b)  
Make sure there is no water leakage from the left and right dry bay condensate drain tubes.

 (c)  
Make sure there is no water leakage near the midspar forward drain fitting.

 S 792-222
 (4)  After three minutes, make sure that a minimum of 236 fluid ounces (6980 ml) of water has collected in the container.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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747-400 MAINTENANCE MANUAL
 S 792-223
 (5)  Look for leaks from the raceway drain as follows:
 (a)  
Put a small empty container below the raceway drain fitting.

 (b)  
Remove the cap or plug from the raceway drain fitting, and let the water drain into the container.

 (c)  
Measure the water that leaked from the raceway drain into the container.

 (d)  
A maximum of 4 ounces (120 ml) of water is permitted.

 NOTE: It is permitted for 2 ounces (60 ml) of water to leak
____ into the fully enclosed cavity of the strut system raceway for each gallon (128 ounces) of applied water. If 2 gallons (256 ounces or 720 ml) was applied, 4 ounces (60 ml) of water leakage is permitted.
 (e)  
Connect the raceway drain fitting to the drain line just below the raceway.

 (f)  
Make sure there is no puddling of water in the strut area.

 NOTE: Puddling is defined as more than 0.5 fluid ounce (15 ml)
____ of water in a continuous pool.
 S 362-224
 (6)  If you found water leaks during the test, do these steps:
 (a)  
If the leak is from a tube, do the procedure to repair the tube (AMM 20-11-05/801).

 (b)  
If the leak is from a seal, do the procedure to seal the applicable area of the leak (AMM 51-31-01/201).

 (c)  
After you repair the leak, do the applicable leak test again.

 S 362-225
 (7)  If you did not collect the correct amount of water and cannot find leaks, do these steps:
 (a)  
Do the task to clear the applicable strut drain.

 (b)  
If you cannot remove the blockage with air, use a thin wire to clear the applicable drain tube.

 (c)  
Continue to remove the blockage in the tube and do the leak test again until you collect the correct amount of water.

 G.  If you will not do more leak checks at this time, put the airplane back to its usual condition.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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747-400 MAINTENANCE MANUAL
 S 162-226
 CAUTION:_______ MAKE SURE YOU KEEP THE STRUT AREA CLEAN.  TOOLS, LOOSE AND
 UNWANTED MATERIALS IN THE STRUT COMPARTMENTS CAN BLOCK THE
 REMOVAL OF THE FLUIDS THROUGH THE STRUT DRAINS.  IF YOU DO NOT
 REMOVE THE UNWANTED MATERIALS, YOU CAN CAUSE DAMAGE TO THE
　
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