A-1000, Rev. 3.
2
Page 13
of 42
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3.1.5
For tongue-and-groove mountings, examine the sides of the groove. The valve tongue fits tightly into the
groove, any peening-over of the edges of the groove may make it difficult to properly fit the valve tongue into
the groove. If the sides of the groove are peened over, make corrections to meet the AAR’s groove tolerances.
3.1.6
Install the new gasket. Ensure it is fully seated. When a groove gasket is fully seated, 1/16" of free space
should remain above the gasket to permit locating and entry of the valve tongue.
CAUTION:
Do not use a sharp tool to press the new gasket into place or gasket damage may result.
3.1.7
For tongue-and-groove mountings, inspect the tongue of a new, reconditioned or retested valve by running
your fingernail around its inner and outer edges to check for damage. The tongue dimensions have diameter
tolerances of ±0.003", thus any excess material on these diameters will make it difficult to fit the tongue into the
groove. If the tongue is peened over, remove excess material to meet AAR tongue tolerances.
CAUTION:
To prevent tongue damage, do not install a valve having damaged sealing surfaces.
3.1.8
Remove the rubber plug from the cover plate.
3.1.9
Position the valve gently into the mounting. Align the body holes over the studs and lower the valve while
positioning the valve tongue in the cover-plate groove.
CAUTION: Tongue Not in Cover-Plate Groove.
Verify that the valve tongue has fit into the cover-plate
groove. It must be so engaged before continuing with the next step or valve damage may result.
3.1.10 Install the nuts and tighten them in 1/3-torque increments in a diagonally
alternating sequence, as shown in Figure 3-2. Consult gasket manufacturer for
recommended torque requirements.
NOTICE:
This is for installation to the car, so the pattern is on the
outside bolts.
CAUTION: Uneven Gasket Compression.
Do not over-tighten the
nuts on one side of the valve as this may tilt the valve and result in
uneven gasket compression.
TIP:
Use a 1-1/4” wrench to tighten mounting nuts.
Figure 3-2 Tightening Sequence
CAUTION
CAUTION
CAUTION
NOTICE
CAUTION
1
2
3
4
