4
Impulse Second Stage Service & Repair Manual
© 1997 U.S. Divers Co., Inc.
pletely depressed with one hand, firmly grasp the adjustment
knob and pull straight out to remove the entire valve module
assembly from the box bottom (see Fig. 2).
CAUTION
: Do not attempt to remove the valve module
assembly from the box bottom without first holding the lever
depressed. Doing so may cause serious damage to the box
bottom, lever, or poppet, which will require their replacement.
10. Remove and discard the O-ring(22a), which will be either on
the inlet end of the valve body, or loose inside the box bottom.
11. Remove the spacer bushing(12) from the inlet opening of the
box bottom, and examine to ensure that it is perfectly round in
its center and shows no signs of damage or deterioration. If
damage or deterioration is found, discard and do not reuse.
12. While holding the valve module secure and horizontal with
the lever facing up, turn the adjustment knob slightly clock-
wise to allow the retaining pin to fall out. Set the pin aside.
NOTE:
If the retaining pin does not easily fall out of the
valve body after the adjustment knob has been turned slight
clockwise, it may be necessary to press it out, using the pin
of the Seat Extraction Tool (P/N 1094-36).
13. Continue to hold the valve module secure, and turn the adjust-
ment knob counter-clockwise until it has disengaged from the
threads of the valve body. Remove and inspect the washer(29)
for any signs of wear or damage, and discard if found.
14. Remove and discard both O-rings(30&31), and set the adjust-
ment knob aside to be cleaned separately in a mild acid bath
(white vinegar), outside of an ultrasonic cleaner.
15. Remove the O-ring(22b) from the valve body and discard.
16. Stand the valve body vertical with the inlet end facing up, so
that the lever hangs down. Gently spread the arms of the lever
evenly apart until the poppet/ LP seat assembly(27) disen-
gages and falls out inside the valve body (see Fig. 3). Relax
the arms of the lever, and lift the valve body straight up to
allow the poppet/ LP seat assembly and spring to fall out.
Remove the spring from the poppet, and set both items aside.
17. While holding one arm of the lever pressed securely against
the side of the valve body, gently pull the other arm out of the
opposite side with thumb and forefinger (see Fig. 4). When it
has disengaged from the valve body, pull the other arm out
and set the lever on a flat surface with the tips facing down.
18. Before performing any further disassembly, closely inspect the
shape of the lever to determine whether it is distorted, cor-
roded, or otherwise damaged. While laying on a flat surface
with the tips facing down, all four tips should rest evenly on
the same plane, without being cocked or bent upward (see Fig.
5). If damage or corrosion is found, discard the lever and do
not attempt to bend it to its original shape or otherwise reuse.
19. Closely examine the poppet spring with a magnifier to ensure
Fig. 2 - Valve Module Removal
Fig. 4 - Removing Lever
Fig. 3 - Disengaging Poppet From Lever
