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C. 3-3/4-inch Dia. Bellows w/Kickoff* Spring (Cont.)
(see Figure 4-2)
5. Position range spring assembly over retainer posts and replace retainer nuts.
6. Insert the tubing between the range springs and tighten inboard lock nut.
7. Zero the pointer by adjusting the spud on the push rod. Be sure that the
kickoff spring is not engaged during this operation.
8. Position the kickoff spring to prevent interference with the coil springs and
tighten the kickoff spring lock nut. If clearance is needed for the wrench
during this operation, note the position of the spud (measure with a scale
or count threads to the end of the push rod) and move the spud for the
required clearance. After the lock nut is tightened, return the spud to the
original position.
Figure 4-2. Kickoff Spring Assembly
NOTE: The lock nut requires a modified 7/16", 12-point box wrench for tight-
ening (Figure 4-3).
Figure 4-3. Wrench Modification
9. Check the back-clearance between the kickoff spring and the slot. Use a
wire feeler gage or comparable measuring device. The clearance will vary
between each individual slot but must be at least 0.005-inch for any one
slot to prevent interference with instrument zero. Add or remove washers
as required to obtain the proper clearance. Tighten the lock nut securely.
10. Install the jam nut and lock the spud to the push rod. Hold with pliers. If the
spud was moved in step 9, return the spud to the proper position before
tightening the jam nut.
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