Aqua Lung ABS SECOND STAGE Technical Maintenance Manual page 12

12
SYMPTOM
Leak or free flow in second stage
Low purge or excessive work of
breathing (full cylinder)
External Air Leakage
Water enters second stage
during inhalation
NOTE:
This is a partial list of possible problems
and recommended treatments. Contact the
Repair Department for assistance with problems
not described here.
Table 1: Troubleshooting Guide
POSSIBLE CAUSE
1. High first stage MP
(should be 135-140 psi).
2. LP seat (8) is worn or damaged.
3. The crown (21) and/or locknut (1) not
correctly adjusted.
4. The crown (21) sealing surface is
damaged.
5. The poppet spring (6) is damaged.
6. The lever (3) is adjusted too high.
1. Low first stage MP
(should be 135-140 psi).
2. The crown (21) and/or locknut (1)
adjusted incorrectly.
3. The lever (3) is adjusted too low.
4. The MP hose (26) is clogged or
obstructed.
5. The lever (3) is bent.
1. MP hose (26) is loose (immersion test).
2. Crown o-ring (20) is damaged.
3. Box bottom (19) is damaged.
1. Demand diaphragm (18) is damaged.
2. The diaphragm (18) is improperly
seated between the box bottom (19)
and the washer (17).
3. The exhaust valve (9) is damaged.
4. The box bottom (19) is damaged. (Check
exhaust valve (9) sealing surface).
5. The mouthpiece (22) is cut or torn.
6. The valve insert o-ring (11) is damaged.
TREATMENT
1. Refer to First Stage Troubleshooting
Guide
2. Replace the seat
3. Reset the crown and/or locknut to
preliminary settings, then repeat
Adjustment Prodecures.
4. Replace crown
5. Replace poppet spring
6. Loosen the locknut
1. Refer to First Stage Troubleshooting
Guide
2. Reset the crown and/or locknut to
preliminary settings, then repeat
Adjustment Prodecures.
3. Tighten the locknut (1)
4. Clean or replace hose
5. Replace lever.
1. Tighten to 40 in/lbs at female second
stage fitting
2. Disassemble and replace o-ring
3. Disassemble and replace box bottom
1. Replace the diaphragm
2. Remove purge cover (15) and
diaphragm retainer (16, then properly
reassemble diaphragm and washer
(17). Check for distortion.
3. Replace the valve
4. Disassemble and replace box bottom
5. Replace the mouthpiece
6. Disassemble and replace o-ring
CAUTION:
Recommended treatments which require
disassembly of the regulator must be performed
during a complete overhaul, according to the
prescribed procedures for scheduled, annual
service. Do not attempt to perform partial service.