TM 9-4120-371-14
(5) Adjustment of door trip mechanism.
Loosen nut on spring adjusting screw.
If door tripped before marker reached green color band, turn screw in to increase spring pressure.
If door tripped with marker past green color band, turn screw out to decrease spring pressure.
Reset (open) door and retest and adjust until door trips at green color band range indicator.
Tighten nut on spring adjusting screw when adjustment is finished.
(6) Close round access cover.
d. Test/Calibration of spring balance assembly (test tool)
(1) Use an accurate scale, postage meter, or similar weighing machine.
(2) Hold the tubular (handle) of the tool and press the tip against the scale.
(3) When 1.30 LBS (1 LB-5 OZ) is indicated on the scale meter, the marker should be on the green color
band range.
(4) If adjustment is necessary
Using an allen wrench, loosen the compression bushing setscrew.
Slide compression bushing in to increase pressure and out to decrease pressure.
When 1.30 LBS (1 LB5 OZ) pressure is indicated, tighten setscrew.
e. See figure 535 for identification of blast damper parts and disassembly/reassembly information.