(b)
All the main rotor disk, hub, and spacer snaps
(c)
Conical-seats
(d)
Fuel fittings
TASK 70-20-00-392-006-N00
5. Sealing Compounds
_________________
A. General
CAUTION: DO NOT USE A SEALING COMPOUND AS AN ALTERNATIVE TO CORRECT PART
_______ FINISH, GOOD ASSEMBLY PROCEDURES, OR CORRECT DIMENSIONS. FAILURE OF THE EQUIPMENT CAN OCCUR.
(1)
You can use sealing compounds to give more protection against small leaks on some surfaces (parts with threads, metal-to-metal parts, and mating parts with gaskets).
(2)
Make sure you fully clean the mating surfaces.
(a) Remove all the unwanted materials (oil, grease, or gasket materials).
(3)
Apply the sealing compound in a very thin layer to the two mating surfaces.
(4)
Install the parts.
(5)
Remove the unwanted sealing compound from the area.
B. Consumable Materials
(1)
A00611 Medium grade sealing compound is approved on threaded fittings.
(2)
D00613 Light grade sealing compound is approved on metal mating faces.
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(3)
A00482 Silicone rubber sealant, RTV-159.
(4)
A00610 Silicone rubber sealant, DC-4 is approved on fittings with threads (does not apply to silicone rubber parts or electrical connectors). Use this material on gasket surfaces to reduce bond to mating surfaces, or to prevent small leakage. Also you can use it on metal mating surfaces.
(5)
A00617 Aviation Form-A-Gasket No. 3 sealing compound is approved on fittings with threads and metal mating surfaces.
(6)
A00619 Parker Sealube sealing compound is approved on fittings with threads and metal mating surfaces.
(7)
A00618 Aviation Form-A-Gasket No. 2 sealing compound is approved on threaded-permanent plugs and inserts.
(8)
G00965 Gredag No. 55 graphite gasket lubricant and Lubriplate No. 130A extreme pressure grease (P04-005) is approved on gasket surfaces to reduce bond, or to prevent small leakage.
C.
Limits on the sealing compounds.
S 912-016-N00
(1) Unless it is specified, do not use sealing compounds at these locations:
(a)
All the connections in the engine fuel system
(b)
All the assemblies that have splines
(c)
All the oil seal rings that are metal
(d)
All the carrier grooves for the oil ring
(e)
All the parts that rub together when the engine operates.
TASK 70-20-00-642-007-N00
6. Gasket Lubricant
________________
A. Consumable Materials
(1)
G00965 Lubricant - Gasket, Gredag No. 55 Graphite
B.
Access
(1)
Location Zone
412 Engine No. 1
422 Engine No. 2
432 Engine No. 3
442 Engine No. 4
C.
Do these steps when you apply Gredag lubricant:
S 642-014-N00
(1) If it is necessary, put a layer of lubricant on the gasket surfaces.
(a) If you do this, the gasket will not bond to the surfaces of the mating parts.
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ALL ú ú N01 Page 206 ú Oct 10/96
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
TASK 70-20-00-402-009-N00
7. Stainless Steel Bolts With Decreased Pitch Diameters
____________________________________________________
A. General
(1)
The engine manufacturer puts bolts that have threads with decreased pitch diameters in the hot sections of the engine.
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