NOTE: The use of lubricant on packings is helpful in preventing twisting, tearing, and cutting of the elastomer during installation. The lubricant shall be applied as a thin, even coat. Recommended lubricants are listed in Table 501, however, packings should be lubricated with lubricant specified in applicable manual.
(2)
If part is threaded, or has sharp edges, keyways, or splines, it may be necessary to install packing on a sleeve. Insert threaded or sharp portions of part into a suitable sleeve and roll packing off sleeve and into the packing groove of part as shown in View B.
(3)
As shown in View C, slowly and carefully slide shaft into bore of body, using a twisting motion, back and forth, so packing will slide past any grooves or cross holes without shearing or clipping.
Assembly
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Typical Installation of Packings
Figure 501
Assembly
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B. Heat-set Seal Installation
Determine the application or Class of the heat set seals prior to attempting installation:
NOTE: Elastomer seals, such as packings, used in sliding applications subject to critical leakage or low hysteresis requirements can be heat set to improve fit and function. Seals to be heat set are classified as follows: Class I, Part No. S8990-X and Class II, Part No. 663700-X.
Class II seals may be heat set in the functional unit but Class I seals shall be heat set in a fixture prior to installation unless specifically authorized otherwise. The fixture used shall duplicate the dimensions of the using hardware. Heat set seals normally incorporate the use of bridge seals. The bridge seal shall be installed over the elastomer seal prior to heat-setting operation.
CAUTION: WHEN A FIXTURE IS USED, CARE SHALL BE EXERCISED IN REMOVING THE HEAT SET SEAL TO PREVENT ROLLING OR OTHERWISE DEFORMING THE SET SHAPE OF THE ELASTOMER. CARE SHALL BE EXERCISED IN INSTALLING HEAT SET SEALS IN THE FUNCTIONAL HARDWARE, IN THE PROPER ATTITUDE.
(1)
Install seals to be heat set into functional hardware or in a fixture specified in applicable manual for unit in work.
(2)
Heat set Class I seal at 515 to 535F (268 to 279C) and Class II seals at 340 to 360F (171 to 182C) for two hours.
(3)
Allow alloy assembly to cool at room temperature prior to removing seals.
C. Forming Lip Seals
If lip seal is not formed, install the seal on pilot specified in applicable manual to form the seal lip in the correct direction.
Assembly
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3. Conical Seal
NOTE: Conical seals are used at specific locations during engine production to preclude leakage. However, conical seals may be used at any flared tubing fitting of appropriate size in fuel and oil systems as a repair to correct leakage at the option of the user.
A. Conical Seal Selection and Lubrication
CAUTION: INPROPER INSTALLATION OF CONICAL SEALS DESCRIBED IN THE FOLLOWING STEPS IS ESSENTIAL TO AVOID FLOW RESTRICTION OR SUBSEQUENT LEAKAGE. CONICAL SEALS ARE TO BE USED ONLY ONCE AND SHALL BE REPLACED AT EACH DISASSEMBLY OF PLUMBING. ENSURE THAT PREVIOUSLY INSTALLED CONICAL SEAL IS REMOVED FROM PLUMBING FITTING BEFORE INSTALLING NEW CONICAL SEAL.
Unless otherwise specified, flared tubing fittings when used with conical seals shall be tightened to torque values specified in Table 502. When conical seals are used, install conical seals and tighten fittings as described in the following steps.
(1)
Select proper conical seal part number for tube assembly being installed. (Refer to Table 502.)
(2)
Lubricate conical seal and threads of plumbing fitting with clean engine oil.
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