(4)  
You can find the limber holes and the drain tubes through the wing stringers. They let the sump fuel and the water drain to the lowest areas of the wing tanks. You must keep the holes and tubes clear of material. This will prevent the collection of the fuel and the water when you drain the tanks (Fig. 701).

 B.
Standard Tools and Equipment

 (1)  
Brush - wire, hand-held

 (2)  
Brush - wire, rotary, stainless steel

 (3)  
Gloves - applicable for steam cleaning, Lyons Safety, Germantown, Wisconsin, USA

 (4)  
Respirator - Full face-supplied, air type, U.S. Bureau of Mines approved

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MAINTENANCE MANUAL

SEE C SEE A
SEE A SEE C
SEE C
SEE A
SEE E WING RIB
TANK END RIB
SEE B
A
STRINGER
DRAIN TUBEB
Limber Hole and Drain Tube Location
Figure 701 (Sheet 1)

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Limber Hole and Drain Tube Location
Figure 701 (Sheet 2)

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MAINTENANCE MANUAL

 (5)
Rubber pants, boots and jacket with hood

 (6)
Source of cold water (at approximately 50 psi)

 (7)
Source of saturated steam

 (8)  
280248 Steam Nozzle - Trigger T-Jet, Spraying Systems Co., Wheaton, Illinois, USA or equivalent

 NOTE: It is recommended that the teflon bushing supplied with this
____ nozzle be replaced with a locally fabricated brass bushing. The nozzle is made to have a source of saturated steam and a source of cold water attached; each supply to be adjusted by a set of valves to maintain a working spray of approximately 100 psi, with a temperature not to be more than 150°F, 6 inches from the nozzle end.
 (9)
Vacuum

 C.
Consumable Materials

 (1)
Tape - pressure sensitive

 D.
References

 (1)
AMM 28-11-00/201, Fuel Tanks

 (2)
AMM 28-11-00/801, Fuel Tanks

 (3)
AMM 28-11-02/401, Reserve and Main Tank Access Door

 (4)
AMM 28-11-04/401, Fuel Sump Drain Valve Primary Poppet

 (5)
AMM 28-11-07/401, Fuel Sump Drain Valve Secondary Poppet

 (6)
AMM 28-26-00/201, Defueling

 (7)
Structural Repair Manual

 E.
Access

 (1)  
Location Zones
 500 Left Wing
 600 Right Wing

 (2)  
Access Panels
 541AB thru 553KB Fuel Tank Access Door, Left
 641AB thru 653KB Fuel Tank Access Door, Right

 F.
Clean the Fuel Tank

 (1)
Defuel the applicable fuel tank (AMM 28-26-00/201).

 S 657-006
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 S 867-007
 WARNING:_______OBEY ALL OF THE FUEL TANK PURGING AND ENTRY PRECAUTIONS. AN INJURY TO A PERSON AND DAMAGE TO THE AIRPLANE CAN OCCUR.
　
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