© ⅯⅯⅩⅢ Kirby Morgan Dive Systems, Inc. All rights reserved. Document # 130318002
117
Kirby Morgan
®
37SS
Chapter 7 - Overpressure Relief / Bleed Valve Overhaul Procedures
Repair parts are available. Normal replacement parts
include the O-ring, soft seat, spring, and hex nut.
The O-ring should be replaced at least annually.
The other parts require replacement only if worn or
damaged. An exploded view of the valve is located
in all KMDSI Helmet and Band Mask Operations
and Maintenance Manuals. The text on the next three
pages refers to the drawing on page 116.
Tools Required.
Torque wrench
1/2
" open-end wrench attachment for torque wrench
1/8
" Allen wrench
Nylon toothbrush
Vinegar, Fresh water
Mild dish soap
Ultrasonic sink, if available
Magnifying glass
New valve body o-ring
7.17.2 Overpressure Relief Valve
Disassembly and Cleaning
1) Turn off the gas supply to the first stage regula
-
tor, then bleed off any remaining pressure. Remove
the first stage regulator from the air/breathing gas
source so it cannot be accidentally turned on, i.e.,
pressurized. Make sure the intermediate pressure in
the regulator hose is also fully drained of pressure.
2) Remove the relief/bleed valve from the regulator
body using the
1/2
" open-end wrench.
3) Remove, cut, and discard the relief/bleed valve
body O-ring.
4) Using the
1/2
" open-end wrench to hold the bleed/
relief body, use the
1/8
" Allen wrench to remove the
Allen head adjustment screw. Then, shake out the
spring and soft seat.
5) Place all parts in the
50/50
solution of vinegar and
water and allow to soak for 15 to 30 minutes. If using
an ultrasonic sink, reduce time to 15 minutes.
B
WARNING
Do not use cleaning solvents (i.e. min-
eral spirits, bleach, etc.) when clean-
ing the relief/bleed valve. The use of
cleaning solvents may lead to failure
of the relief/bleed valve.
6) Using the nylon toothbrush, brush all components
to remove corrosion and mineral deposits. Then, rinse
with fresh water and blow or air dry.
7) Using the magnifying glass, carefully inspect all
components for excessive corrosion and/or damage.
Replace the spring and/or adjustment nut, if either
part is excessively corroded or shows signs of wear
and/or damage.
Inspect the soft seat for nicks, cuts, and wear and
replace if any damage is found. Replace the entire
assembly if any damage to the valve body is present.
NOTE: A deep groove in the soft seat is normal.
Replacement is only necessary if the rubber seat is
deteriorated, cut, and/or chipped.
7.17.3 Overpressure Relief Valve
Reassembly
1) After cleaning, inspection and/or parts replace
-
ment, reassemble the valve by installing the soft seat,
spring, and adjustment nut. Screw the adjustment nut
down until it is approximately
1/2
thread from being
flush with the top of the valve body.
2) Lightly lubricate a new body O-ring, then install
on the valve body.
3) Test the relief/bleed valve according to the test
procedure below.
7.17.4 Overpressure Relief Valve Lift Check/
Setting
Tools required:
Adjustable first stage scuba regulator or controlled
adjustable pressure source
Intermediate pressure test gauge
Torque wrench
1/2
" open-end wrench adapter for torque wrench
1/8
" Allen wrench
HP air source (SCUBA tank) with at least 500 p.s.i.g.
(34.4 bar).
Mild dish soap
