Apeks FSR Series User manual

TECHNICAL MAINTENANCE MANUAL
FSR/FST FIRST STAGE

2
CONTENTS
Copyright Notice..........................................................................................................3
General Guidelines......................................................................................................3
General Conventions ..................................................................................................3
DISASSEMBLY PROCEDURES...................................................................................4
REASSEMBLY PROCEDURES....................................................................................7
ADJUSTING THE FIRST STAGE .................................................................................9
FINAL ASSEMBLY .....................................................................................................10
FINAL TESTING..........................................................................................................10
Table 1: Troubleshooting Guide ............................................................................... 11
Table 2: List of Tools and Service Kits .................................................................... 12
Table 3: Torque Specications ................................................................................. 13
Table 4: Test Bench Specications ......................................................................... 13
Table 5: Recommended Cleaners and Lubricants .................................................13
Procedure A: Cleaning and Lubricating.................................................................. 14
Maintenance Notes....................................................................................................15
XTX200 TUNGSTEN, XTX200 and ATX200, Exploded View ..................................16
XTX100 and ATX100, Exploded View ....................................................................... 17

3
Copyright Notice
This manual is copyrighted, all rights reserved. It may not, in whole or in
part, be copied, photocopied, reproduced, translated or reduced to any
electronic medium or machine-readable form without prior consent in
writing from Aqua Lung International. It may not be distributed through
the internet or computer bulletin board systems without prior consent in
writing from Aqua Lung International.
©2008 Aqua Lung International
Apeks FSR/FST First Stage Technical Maintenance Manual
Introduction
This manual provides factory prescribed procedures for the correct
service and repair of the Aqua Lung or Apeks regulator products
described in this manual. It is not intended to be used as an instructional
manual for untrained personnel.
The procedures outlined within this manual are to be performed only by
personnel who have received Factory Authorized training through an
Apeks Service & Repair Seminar. If you do not completely understand all
of the procedures outlined in this manual, contact Aqua Lung® to speak
directly with a Technical Advisor before proceeding any further.
Warnings, Cautions, & Notes
Pay special attention to information provided in warnings, cautions and
notes that are accompanied by one of these symbols:
WARNINGS indicate a procedure or
situation that may result in serious
injury or death if instructions are not
followed correctly.
CAUTIONS indicate any situation or
technique that will result in potential
damage to the product, or render the
product unsafe if instructions are not
followed correctly.
NOTES are used to emphasize important
points, tips and reminders.
Scheduled Service
If the regulator is subjected to less than 50 dives per year, it is permis-
sible to overhaul it every other year with an inspection procedure being
performed on the “off” years. For example:
Year #1 : Inspection
Year #2 : Overhaul
Year #3 : Inspection
Year #4 : Overhaul, and so on.
Both Inspections and Overhauls need to be documented in the Annual
Service & Inspection Record in the back of the Owner's Manual to keep
the Limited Lifetime Warranty in effect. If a regulator is subjected to more
than 50 dives per year, it should receive the complete overhaul.
An Ofcial Inspection consists of:
1. A pressurized immersion test of the entire unit to check
for air leakage.
2. Checking for stable medium pressure that is within
the acceptable range.
3. Checking for opening effort that is within the
acceptable range.
4. Checking for smooth operation of the control knob and
venturi switch.
5. A visual inspection of the lter for debris or discoloration.
6. A visual inspection of the exhaust valve to see that it is in
good shape and that it’s resting against a clean surface.
7. A visual inspection of the mouthpiece looking for tears
or holes.
8. Pulling back hose protectors and checking that the hoses
are secure in the hose crimps.
If a regulator fails item #1,2,3 or 4, the entire regulator should be
overhauled. If a regulator fails 4,5,6 or 7, it will be up to the technician’s
discretion whether or not a full overhaul is required.
General Guidelines
1. In order to correctly perform the procedures outlined in this
manual, it is important to follow each step exactly in the order
given. Read over the entire manual to become familiar with all
procedures before attempting to disassemble the product in this
manual, and to learn which specialty tools and replacement parts
will be required. Keep the manual open beside you for reference
while performing each procedure. Do not rely on memory.
2. All service and repair should be carried out in a work area
specically set up and equipped for the task. Adequate lighting,
cleanliness, and easy access to all required tools are essential for
an efcient repair facility.
3. As the regulator is disassembled, reusable components should
be segregated and not allowed to intermix with nonreusable parts
or parts from other units. Delicate parts, including inlet ttings and
crowns which contain critical sealing surfaces, must be protected
and isolated from other parts to prevent damage during the clean-
ing procedure.
4. Use only genuine Apeks parts provided in the overhaul parts kit
for this product. DO NOT attempt to substitute an Apeks part with
another manufacturer’s, regardless of any similarity in shape
or size.
5. Do not attempt to reuse mandatory replacement parts under any
circumstances, regardless of the amount of use the product has
received since it was manufactured or last serviced.
6. When reassembling, it is important to follow every torque
specication prescribed in this manual, using a calibrated torque
wrench. Most parts are made of either marine brass or plastic, and
can be permanently damaged by undue stress.
7. In order to make the regulator compatible with nitrox up to 40%
O2 (EAN40), the regulator must be properly cleaned, lubricated
and assembled using genuine Aqua Lung® or Apeks replacement
parts. In addition, assembly must be carried out in a clean
environment using powderless, latex gloves or equivalent. For more
detailed information, be sure to read Procedure A: Cleaning and
Lubrication at the back of this manual.
General Conventions
Unless otherwise instructed, the following terminology and techniques
are assumed:
1. When instructed to remove, unscrew, or loosen a threaded
part, turn the part counterclockwise.
2. When instructed to install, screw in, or tighten a threaded
part, turn the part clockwise.
3. When instructed to remove an o-ring, use the pinch method
(see illustration below) if possible, or use a brass or plastic o-ring
removal tool. Avoid using hardened steel picks, as they may dam-
age the o-ring sealing surface. All o-rings that are removed are
discarded and replaced with brand new o-rings.
4. The following acronyms are used throughout the manual: MP is
Medium Pressure; HP is High Pressure; LP is Low Pressure.
5. Numbers in parentheses reference the key numbers on the
exploded parts schematics. For example, in the statement,
“...remove the o-ring (7) from the crown (8)...”, the number 7 is
the key number to the crown o-ring.
Pinch Method
Press upwards on sides of o-ring to
create a protrusion. Grab o-ring or
insert o-ring tool at protrusion.

4
CAUTION: Use only a plastic or brass o-ring
removal tool (pn 944022) when removing o-rings
to prevent damage to the sealing surface. Even
a small scratch across an o-ring sealing surface
could result in leakage. Once an o-ring sealing
surface has been damaged, the part must be
replaced with new. DO NOT use a dental pick or
any other steel instrument.
NOTE: Before performing any disassembly, refer
to the exploded parts drawing, which references all
mandatory replacement parts. These parts should
be replaced with new, and must not be reused
under any circumstances – regardless of the age of
the regulator or how much use it has received since
it was last serviced.
DISASSEMBLY PROCEDURE
1. Use an 11/16 open end wrench to remove the MP hose from
the rst stage body (12). Using the o-ring removal tool (pn
944022), remove the o-ring from the male end of the hose.
5. Using the pin spanner (AT30), remove the end cap (1). With
your nger, push out the hydrostatic diaphragm (2).
6.
Tip the body over and
remove the hydrostatic
transmitter (4).
4. Install vice mounting tool (pn
100395) into the open HP port.
2. Pull back the hose
protectors and inspect the
hose crimps. If the crimp
is damaged or the hose is
pulling out of the crimp, the
hose must be replaced.
3. Using a 5mm hex key,
remove a single HP
blanking plug (27).
7. Using a 6mm hex key, remove the spring adjuster (5). Lift out
the main spring (8).
8. Secure the vice mounting
tool into a bench vise.
Using the pin spanner
(AT30), remove the
diaphragm clamp (7).
Removal of Diaphragm Clamp (TX & ATX series)

FSR/FST First Stage Technical Maintenance Manual 5
8. Secure the vice mounting tool into a bench vise. Lift of the
molded ring (6). Using the 34mm thin wrench (pn AT47)
remove the diaphragm clamp (7).
10. To remove the diaphragm (10), insert LP air nozzle into the
MP port. While holding your thumb over the diaphragm, inject
a small blast of air into the MP port to pop out the diaphragm.
Lift out the valve lifter (11).
NOTE: The thickness of the wrench must not exceed
11mm or it will not t between the thread and the ang.
11. Turn the rst stage over and using a 6mm hex key, remove
the HP balance plug (19). Separate the HP valve (15) and
spring (16) from the HP plug.
13.
Place the rst stage body onto the padded surface with the
MP side facing up (diaphragm side). Using a small wooden
dowel, insert the dowel into the center hole at a slight angle.
Press on the inside edge of the crown (14). To keep the
crown from tilting, press evenly around the perimeter of the
crown. Remove the o-ring (13) from the crown.
Removal of Diaphragm Clamp (XTX, Black Pearl &
Tungsten Series)
9. Lift out the spring carrier (9).
12. Remove the o-rings (13 & 18) from the outside of the HP
plug (19). Using a brass or plastic o-ring tool, carefully
remove the o-ring (17) from the inside of the HP plug.
CAUTION: Before proceeding, make sure you are
working over a padded surface; otherwise, damage to
the crown could occur.
14. Remove the o-ring (13)
from the crown (14).
NOTE: If the crown tilts and gets stuck inside the body, turn
the body over and straighten the crown before proceeding.
Removal of Crown (FSR Models Only)
NOTE: FST models do not have a removeable crown. The
crown is machined inside the body.

6
15. Install body in bench vise, remove the yoke clamp screw (25).
Peel the protective cap (23) off the yoke clamp (20).
16. Using a 3/4” box end wrench, remove the yoke clamp
connector (21) and lift off the yoke clamp (20). Remove the
body from the vise and unthread the vise mounting tool.
17. Insert a dowel through the
open end of the yoke clamp
connector (21) and push
out the lter guard (22).
18. Install body in bench vise. After removing the protective cap
(32) from top of DIN handwheel (34), use a 6mm hex key to
loosen and remove the handwheel connector (33). Lift the
handwheel (34) off the body.
19. Remove the o-ring (13) and lter (35) from the backside of
the handwheel connector (33). Remove the face o-ring (24).
20. Using a 5mm hex key, remove the remaining blanking plugs
(27,31) from the body (12). Remove all o-rings (13,28) from
the blanking plugs.
NOTE: Up until September 2002, Apeks used a white
disc lter known as the Porvair lter in it’s yoke model
rst stages. While Porvair was an excellent lter for
air, it was determined to not be acceptable for use
with enriched air nitrox (EAN). Since Apeks preferred
all of it’s models to be EAN40 compatible new, out of
the box, the Porvair lter was discontinued. Apek’s
standard conical lter (pn AP1472 as used with the DIN
connection) was substituted. Please note that where
the Porvair lter was loaded into the front of the yoke
connector, the conical lter gets loaded from the back of
the connector. To enhance the cosmetics of a regulator
inlet with a conical lter installed, a new lter guard
(AP1406/1) was designed to install into the front of the
connector. DO NOT mistake the lter guard as a lter. It
is to be used only in conjunction with the conical lter.
Before starting reassembly, perform parts clean-
ing and lubrication in accordance with Procedure
A: Cleaning and Lubricating (p. 16).
THIS ENDS DISASSEMBLY
Removal of Yoke Connection
NOTE: For removal of DIN connection, go directly to step 18
Removal of DIN Connection
Removal Porvair lter

FSR/FST First Stage Technical Maintenance Manual 7
1. Install o-ring (13) onto the crown (14). Slide the crown onto the
seat installation tool (pn 109437) with the sealing edge against
the plastic handle of the tool. Insert the crown into the body
and press it into place. Pull the tool out and use the blunt end
to make sure the crown is properly seated.
2. Turn the body (12) over
so the MP side is facing
upward. Drop the valve lifter
(11) through the center hole.
5. Thread the diaphragm clamp (7) onto the body (12) until hand
tight. Using a 6mm hex key, thread the adjustment screw
(5) into the diaphragm clamp until the last two threads of the
adjustment screw are still visible.
REASSEMBLY PROCEDURE
3. Press a new diaphragm
(10) into the body. Run your
nger around the edge of
the diaphragm to make sure
it is properly seated.
4. Place the spring carrier (9), at side down in the center of the
diaphragm (10). Set the main spring (8) on the spring carrier.
6. Thread a vise mounting tool
into the HP port and secure
into a bench vise. Using
the pin spanner, tighten the
diaphragm clamp (7) until it
stops (metal meets metal).
Installation of Diaphragm Clamp (TX & ATX Series)
Installation of Diaphragm Clamp (XTX, Black Pearl &
Tungsten Series)
7. Thread a vise mounting tool into the HP port and secure into a
bench vise. Using a 34mm thin wrench (pn AT47), tighten the
diaphragm clamp (7) until it stops (metal to metal). Slide on
the molded ring (6).
NOTE: The thickness of the wrench must not exceed
11mm or it will not t between the thread and the ang.
8. Install o-ring (17) into the end of the HP balance plug (19).
Install o-rings (13 & 18) onto the outside of the HP plug.

8
9. Press the spring (16) onto the end of the HP balance plug (19).
Pass the stem of the HP seat (15) through the spring and into
the HP plug.
10. Insert the HP plug assembly into the body (12). Using a in/lb
torque wrench and a 6mm hex key adapter, torque the HP
plug to 70 in/lbs (8 Nm).
11.
Press the lter shield (22)
with the raised tabs fac-
ing outward into the yoke
clamp connector (21).
13. Hold the rst stage with
the inlet opening facing
downward. Pass the yoke
connector (21) through the
yoke (20) and into the body
(12). Tighten by hand.
14. Using a vise mounting
tool, install the rst stage
into a bench vise. With a
ft/lb torque wrench and a
3/4” box wrench, torque
the yoke clamp connector
(21) to 14.7 ft/lbs (20 Nm).
Installation of Yoke Connection
15. Attach the dust cap (23) to the yoke clamp (20) by stretch-
ing it over the ange at the top of the yoke clamp. Thread the
yoke clamp screw (25) into the yoke clamp. Remove the rst
stage from the bench vise, remove vise mounting tool.
CAUTION: You must hold the yoke clamp assembly
vertically while being installed. Failure to do this can
cause the o-ring to not seat properly which in turn
will create a HP leak.
NOTE: For installation of DIN connection, go directly to step 16
12.
Insert the small end of the conical lter (35) into the threaded
end of the yoke clamp connector (21). Install a unlubricated
o-ring (13) into the end of the connector.
16. Install a unlubricated o-ring
(24) into the face of the
handwheel connector (33).
Installation of DIN Connection
NOTE: After completing the yoke installation, go directly to
ADJUSTING THE FIRST STAGE on page 9.

FSR/FST First Stage Technical Maintenance Manual 9
17. Insert the small end of the conical lter (35) into the threaded
end of the handwheel connector (33). Insert an unlubricated
o-ring (13) into the handwheel connector around the lter.
ATX 200/100/50
ATX 40/20
2. Install o-rings (13 & 28) onto
the blanking plugs (27 & 31).
Using a 5mm hex key, install
the blanking plugs into the ap-
propriate ports in the body (12).
1. Attach the rst stage (with
no blanking plugs installed)
to a fully charged (3000
psi/206 bar) cylinder. Slowly
open the cylinder valve and
blow through the rst stage
to remove any particles or
contaminants.
WARNING: Compressed air can be highly explosive
and is dangerous if misused. Ensure cylinder valve
is opened slowly. Use eye and ear Personal Protec-
tive Equipment when performing any tests involving
compressed air.
18. Hold the rst stage with
the inlet opening fac-
ing downward. Pass the
handwheel connector (33)
through the threaded end
of the handwheel (34) and
into the body (12). Tighten
by hand.
CAUTION: You must hold the DIN connector assem-
bly vertically while being installed. Failure to do this
can cause the o-ring to not seat properly which in
turn will create a HP leak.
19. Using a vise mounting tool,
install the rst stage into
a bench vise. With a ft/lb
torque wrench and a 6mm
hex key adapter, torque the
handwheel connector (33)
to 14.7 ft/lbs (20 Nm). Re-
move the rst stage from
the bench vise, remove the
vise mouting tool.
ADJUSTING THE FIRST STAGE
NOTE: First stage models in the ATX and TX range have a
1/2” main MP port for the second stage. First stage models in the
XTX range have a 3/8” main MP port for the second stage.
WARNING: If the pressure gauge rapidly exceeds 145 psi/10
bar, there is a HP leak. Quickly close the cylinder valve and
purge the second stage, or reopen the relief valve of the test
gauge and close the cylinder. Failure to do so may cause a
rupture to the MP hose and/or MP gauge, which in turn can lead
to personal injury. Refer to Table 1: Troubleshooting Guide, p.
11 for the causes of high or unstable MP.
CAUTION: Before pressurizing the rst stage, it is important
to have a properly adjusted second stage attached to the rst
stage. This will provide a safety relief valve if the MP exceeds
145 psi/10 bar. Failure to relieve increasing MP may result in
damage to the test gauge or the MP hose.
3. Install MP gauge (pn 111610) to a MP hose and thread the
hose into the open MP port. Open the relief valve. If your test
gauge does not have an overpressure relief valve, then it is
vital that a properly adjusted second stage is attached to the
rst stage to act as an overpressure valve in the event of a
HP leak. Attach the rst stage to a calibrated test bench or a
cylinder lled to 3000 psi/206 bar.
4. With the relief valve open on the gauge, slowly open cylinder
valve and pressurize the rst stage. If the MP rapidly exceeds
145 psi (10 bar), close the cylinder immediately and purge the
line; this means there is an HP leak..
5. If no leaks are detected, ad-
just using a 6mm hex key.
To increase the MP, turn the
adjustment screw in 1/8 turn
increments clockwise. Using
the relief valve on the gauge,
cycle the first stage several
times after each adjustment.
To decrease the MP, turn in the
adjustment screw in 1/8 turn
increments counter-clockwise. Using the relief valve on the gauge,
cycle the rst stage several times after each adjustment. Set the MP
to 130-145 psi (9-10 bar).
6. Let the rst stage stand for several minutes. Check that the
MP remains stable. If the MP rises more than 5 psi (0.3 bar), it
indicates a leak. If the MP is stable, close the valve, purge the
line, and pressurize once again to perform the nal check.
WARNING: Be certain not to install a MP hose into the HP port
via an adapter. Doing so may cause the hose to rupture when
pressurized, and could result in serious personal injury.

10
1. With the rst stage still pressurized, insert the hydrostatic
transmitter (4) into the dry chamber. Press the hydrostatic
diaphragm (2) into the end cap (1).
2. Thread the end cap (1) onto the dry chamber until hand tight.
Using the pin spanner (pn AT30), tighten the end cap until
snug. Recheck the MP to conrm it has not changed.
3.
Close the cylinder valve and depressurize the regulator. Re-
move the test gauge and reinstall the blanking plug.
FINAL ASSEMBLY
NOTE: Do not confuse bubbles from trapped air with a true leak. If
there is an air leak, bubbles will come out in a constant stream.
3. Assuming there are no leaks, close the cylinder valve and
depressurize the regulator. Remove the rst stage from the
cylinder valve and secure the dust cap in place.
THIS CONCLUDES THE SERVICE PROCEDURES
FOR THE FSR/FST FIRST STAGE.
External Leak Test
1. After disconnecting the MP test gauge from the rst stage,
connect the rst stage to a scuba cylinder lled to approxi-
mately 3000 psi (206 bar). Slowly open the cylinder valve to
pressurize the regulator and submerge the entire system in a
test tank of clean water.
2.
Observe any bubbles arising from the submerged regulator
over a one minute period. The recommended time is neces-
sary due to slower bubble formation that occurs in smaller
leaks. Bubbles indicate a leak, this would require the system
to be disassembled at the source to check sealing surfaces,
assembly sequence and component positioning in order to cor-
rect the problem(s). If any bubbles are visible, refer to Table
1: Troubleshooting Guide, p. 11.
FINAL TESTING PROCEDURES

11
Table 1: Troubleshooting Guide
SYMPTOM POSSIBLE CAUSE TREATMENT
.High Pressure Creep
(also causes second-stage leaks)
1. HP valve (15) worn or damaged. 1. Replace HP valve
2. Valve seat o-ring (13) damaged or worn 2. Replace valve seat (crown)
3.
Removeable HP valve seat (crown) (14)
worn or damaged 3. Replace o-ring
4. HP plug (19) internal wall damaged 4. Replace HP plug
5. HP o-ring (17) damaged or worn 5. Replace o-ring
6. HP plug o-ring (13) damaged or worn. 6. Replace o-ring
7. HP valve seat in body (12) worn or
damaged.(FST only) 7. Replace body
External Air Leakage
Or
Hydrostatic diaphragm distended or
burst
1. Blanking plug o-rings (13,28,29) worn or
damaged 1. Replace o-rings
2. Diaphragm (10) worn or damaged 2.
Replace diaphragm
3. Hydrostatic diaphragm (2) worn or dam-
aged 3. Replace hydrostatic diaphragm
4. Diaphragm seating surface damaged 4. Replace body
5. Diaphragm clamp loose 5. Tighten diaphragm clamp
6. Connector o-ring (13) worn or damaged 6. Replace o-ring
7. HP plug o-ring (18) worn or damaged 4. Replace o-ring
Restricted Air Flow or High Inhalation
Resistance Through Entire System
1. Cylinder valve not completely opened 1. Open valve; check ll pressure
2. Cylinder valve needs service. 2. Switch to different cylinder
3. Filter (35) is clogged 3. Replace lter
4. Very low medium pressure. 4. Adjust MP to between 130-145 psi
(9-10 bar)
NOTE: This is a partial list of possible problems and recommended treatments.
For more information, refer to the second-stage troubleshooting guide, or con-
tact Apeks Technical Service Department for assistance with problems
not described here.
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.

12
PART # DESCRIPTION APPLICATION
111610 Medium Pressure Testing
944022 Removal/Installation of O-rings
109437 Seat Removal/Replacement
AT30 Removal/Installation of Diaphragm Clamp & End Cap
AT47 Removal/Installation of Diaphragm Clamp (Blk Pearl, Tung-
sten, XTX models)
100395 Mounting First Stage into Vise
N/A Disassembly/Assembly
N/A Disassembly/Assembly
N/A Apply torque to parts listed in Table 3:
Torque Specications, p. 13
N/A Apply torque to parts listed in Table 3:
Torque Specications, p. 13
N/A Apply torque to parts listed in Table 3:
Torque Specications, p. 13
N/A Apply torque to parts listed in Table 3:
Torque Specications, p. 13
Apply torque to parts listed in Table 3:
Torque Specications, p. 13
N/A Magnier with Illumination Sealing surface inspection
N/A Ultrasonic Cleaner Brass and stainless steel parts cleaning
AP0241/AA Universal First Stage Repair Kit
Table 2: List of Tools and Service Kits
Vise Mounting Tool
Pin Spanner
MP Test Gauge
9/16, 5/8, 11/16, 3/4 Open End Wrench
Hex Key (5mm, 6mm)
3/4” Box Wrench
O-ring Tool Set
Seat Extraction/Installation Tool
9/16, 5/8, 11/16 Crowfoot
34mm Thin Wrench
5mm, 6mm Hex Key Adapter
Torque Wrench (30 - 120 in/lbs)
Torque Wrench (10 - 150 ft/lbs)

13
Table 3: Torque Specications
PART # DESCRIPTION / KEY ITEM # TORQUE
AP1407
AP1407/S
AP1471
AP1471/S
Yoke Connector (21)
DIN Handwheel Connector (33)
14.7 ft/lbs
20 Nm
AP5309
AP5309B HP Balance Plug (18) 70 in/lbs / 8 Nm
AP1408,
AP1413
MP Blanking Plug (31) or hose,
HP Blanking Plug (27) or Hose
40 in/lbs
4.5 Nm
Table 4: Test Bench Specications
TEST CONDITION SPECIFICATION
Leak Test Inlet 2500 - 3000 psig (206 bar) No leaks allowed
MP Inlet 2500 - 3000 psig (206 bar) 130 - 145 psi (9 - 10 bar)
Medium Pres-
sure Creep Inlet 2500 - 3000 psig (206 bar) 5 psi (0.25 bar) max for 15 seconds
after cycling (purging) regulator
Table 5: Recommended Cleaners and Lubricants
LUBRICANT/CLEANER APPLICATION SOURCE
Christo-Lube MCG 111 All o-rings
Aqua Lung, PN 820466, or
Lubrication Technologies
310 Morton Street
Jackson, OH 45640
[phone]
Oakite #31 Acid bath for reusable stainless steel and
brass parts.
Oakite Products, Inc.
50 Valley Road
Berkeley Heights, NJ 07922
White distilled vinegar Acid bath for reusable stainless steel
and brass parts. “Household” grade
Liquid dishwashing detergent
(diluted with warm water)
Degreaser for brass and stainless steel
parts; general cleaning solution for plastic
and rubber.
“Household” grade
CAUTION: Silicone rubber requires no lubrication or preservative treatment.
DO NOT apply grease or spray to silicone rubber parts. Doing so may cause
a chemical breakdown and premature deterioration of the material.
CAUTION: Do not use muriatic acid for the cleaning of any parts. Even if
strongly diluted, muriatic acid can harm chrome plating and may leave a
residue that is harmful to o-ring seals and other parts.

14
Aqua Lung and Apeks First Stages and Nitrox
When it comes to issues of nitrox safety and compatibility, the concerns lie primarily with the rst stage as it is subjected to high inlet
pressures. High inlet pressures lead to adiabatic compression or heating of the gas. The Aqua Lung or Apeks regulator product
described in this manual, when properly cleaned and assembled, is authorized for use with enriched air nitrox (EAN) that does not
exceed 40% (EAN 40). It is authorized because it has undergone adiabatic compression testing and the authorized service kit
components and lubricants are compatible in elevated oxygen environments. During cleaning, a mild detergent must be used to remove
condensed hydrocarbons (compressor oils) from the inside passageways of the rst stage. For the rst stage to remain EAN40
compatible, only use hyper ltered compressed gas (hydrocarbons < 0.1 mg/m3). Ordinary compressed breathing air (Grade E) usually
does not meet this criterion. Once ordinary breathing air is used, the rst stage is no longer EAN40 compatible until it is cleaned and
serviced again.
Although regulator second stage components are not exposed to high pressure EAN, Aqua Lung recommends that the same cleaning
procedures be followed for the complete regulator. This prevents the possibility of cross contamination and guarantees the cleanliness
of the entire regulator.
Cleaning Brass and Stainless Steel Parts
1. Preclean in warm, soapy water* using a nylon bristle tooth brush.
2. Thoroughly clean parts in an ultrasonic cleaner lled with soapy water. If there are stubborn deposits, household white distilled
vinegar (acetic acid) in an ultrasonic cleaner will work well. DO NOT place plastic, rubber, silicone or anodized aluminum parts
in vinegar.
3. Remove parts from the ultrasonic cleaner and rinse with fresh water. If tap water is extremely “hard,” place the parts in a bath
of distilled water to prevent any mineral residue. Agitate lightly, and allow to soak for 5-10 minutes. Remove and blow dry
with low pressure (25 psi) ltered air, and inspect closely to ensure proper cleaning and like-new condition.
Cleaning Anodized Aluminum, Plastic & Rubber Parts
Anodized aluminum parts and parts made of plastic or rubber, such as box bottoms, box tops, dust caps, etc., may be soaked and
cleaned in a solution of warm water mixed with mild dish soap. Use only a soft nylon toothbrush to scrub away any deposits. Rinse in
fresh water and thoroughly blow dry, using low pressure ltered air.
CAUTION: Do not place plastic and rubber parts in acid solutions.
Doing so may alter the physical properties of the component,
causing it to prematurely degrade and/or break.
Cleaning Hoses
1. Hose ttings: Ultrasonically clean with soapy water*; vinegar OK on tough corrosion
2. Run soapy water through hose if needed
3. Thoroughly rinse with fresh water
4. Blow out hose before installing
Lubrication and Dressing
Wear powderless, latex gloves when handling and lubricating o-rings. Keeping internal parts free from skin oils and other contaminates
is important when running enriched air nitrox through a rst stage. All o-rings should be lubricated with Christo-Lube®MCG-111. Dress
the o-rings with a very light lm of grease, and remove any visible excess by running the o-ring between thumb and forenger. Avoid
applying excessive amounts of Christo-Lube® grease, as this will attract particulate matter that may cause damage to the o-ring.
*Soapy water is dened as “household” grade liquid dishwashing detergent diluted in warm water.
Procedure A: Cleaning and Lubricating

15
Maintenance Notes

16
.......AP5720PVDS Body, FSR, Tungsten, ATX
13 .......AP1409 O-ring
14 .......AP1419 HP Valve
15 .......AP1415 Spring
16 .......AP1299 O-ring
17 .......AP1300 O-ring
18 .......AP5309 HP Balance Plug, ATX
.......AP5309B HP Balance Plug, XTX, Tungsten
19 .......AP1403/S Yoke Clamp, Satin, ATX
.......AP1403 Yoke Clamp, XTX
.......AP1403PVDS Yoke Clamp, PVD, Tungsten
20 .......AP1407/S Yoke Clamp Connector, Satin, ATX
.......AP1407 Yoke Clamp Connector, XTX, Tungsten
21 .......AP1406/1 Filter Guard
22 .......AP1404 Protective Cap
23 .......AP1166 O-ring
24 .......AP1402 Yoke Clamp Screw
25 .......AP5723 Decal, Body, XTX 200, ATX 200
.......AP5739 Decal, Body, ATX, Tungsten
.......AP6239 Decal, Body, XTX, Tungsten
26 .......AP1413 7/16” Blanking Plug
27 .......AP1445 O-ring
28 .......AP1410 O-ring, ATX
29 .......AP1487 1/2" Blanking Plug, ATX
30 .......AP1408 3/8" Blanking Plug
31a .......AP1470/S Handwheel, 300 Bar, Satin, ATX
31b .......AP6201 Handwheel, 300 Bar, XTX, Tungsten
32 .......AP1471/S Handwheel Connector, Satin, ATX
.......AP1471 Handwheel Connector, XTX, Tungsten
33 .......AP6202 Protective Cap, DIN
34 .......AP1472 Conical Filter
35 .......AP5721 Removeable HP Valve Seat (Crown)
Key # .Part # Description
Part numbers in BOLD ITALICS indicate standard overhaul replacement part.
XTX 200 Tungsten • XTX 200 • ATX 200 Tungsten • ATX 200
(FSR Style)
.......AP0363 XTX200, First Stage only, w/Yoke
.......AP03631 XTX200, First Stage only, w/DIN
.......AA0210 ATX200, First Stage only, w/Yoke
.......AA0210-1 ATX200, First Stage only, w/DIN
.......AP0241/AA Service Kit, Diaphragm First Stage
.......AP0211/S DIN Connector, Satin, ATX
.......AP0620 DIN Connector, Comolded, XTX
.......AP0620PVDS DIN Connector, Tungsten
1 .......AP1484/S Environmental End Cap, Satin, ATX
.......AP1484 Environmental End Cap, XTX
.......AP1484PVDS Environmental End Cap, PVD, Tungsten
2 .......AP1482 Hydrostatic Diaphram, ATX
.......AP14821 Hydrostatic Diaphram, XTX, ATX Tungsten
.......AP1482T Hydrostatic Diaphragm, XTX, Tungsten
3 .......AP5724 Decal, ATX
4 .......AP1483 Hydrostatic Transmitter
5 .......AP1474 Spring Adjuster
6 .......AP5725 Molded Logo Ring, XTX
7a .......AP1473 Diaphragm Clamp, Satin, ATX
7b .......AP14731 Diaphragm Clamp, XTX
8 .......AP1475 Spring
9 .......AP1476 Spring Carrier
10 .......AP1478 Diaphragm
11 .......AP5722 Valve Lifter
12 .......AP5101 Body, FSR, 3/8" MP Port, XTX
.......AP5101PVDS Body, FSR, Tungsten, XTX
Key # .Part # Description
27
11
18
17
13
16
15
14
35
13
26
30
12
1
29
34
13
34
13
28
19
22
23
21
20
23
23
32
31a
33
13
25
24
23
5
6
8
9
10
31b
4
7a
NOTE: In September 2002, the ATX
200 rst stage transitioned from a
hi-gloss black chrome nish to a
satin chrome nish. Specically,
the parts affected are key item #1,
12, 20 and 21. These parts will no
longer be available in black chrome.
Should you need to replace one of
these, you will need to order the
part in satin.
7b
14.7 ft/lbs
20 Nm
70 in/lbs
8 Nm
40 in/lbs
4.5 Nm
40 in/lbs
4.5 Nm

FSR/FST First Stage Technical Maintenance Manual 17
17
22
19
28
30
20
27
25
Part numbers in BOLD ITALICS indicate standard overhaul replacement part.
XTX 100 • ATX 100
(FST Style)
.......AP0362 XTX100, First Stage only, w/Yoke
.......AP0535 ATX, First Stage only, w/Yoke
.......AP0241/AA Service Kit, Diaphragm First Stage
.......AP0211/S DIN Connector
1 .......AP1484/S Environmental End CAP
2 .......AP14821 Hydrostatic Diaphragm, XTX
.......AP1482 Hydrostatic Diaphragm, ATX
3 .......AP1477 Environmental Decal, ATX
4 .......AP1483 Hydrostatic Transmitter
5 .......AP1474 Spring Adjuster
6 .......AP5725 Molded Logo Ring, XTX
7a .......AP14731 Diaphragm Clamp, XTX
7b .......AP1473 Diaphragm Clamp, ATX
8 .......AP1475 Spring
9 .......AP1476 Spring Carrier
10 .......AP1478 Diaphragm
11 .......AP1479 Valve Lifter
12 .......AP5102 Body, FST, 3/8” MP Port, XTX
.......AP5300/S Body, FST, 1/2” MP Port, ATX
13 .......AP1409 O-ring
14 .......AP1419 HP Valve
15 .......AP1415 Spring
16 .......AP1299 O-ring
17 .......AP1300 O-ring
18 .......AP5309 HP Balance Plug
19 .......AP1403/S Yoke Clamp
20 .......AP1407/S Yoke Clamp Connector
21 .......AP1406/1 Filter Guard
22 .......AP1404 Protective CAP
23 .......AP1166 O-ring
24 .......AP1402 Yoke Clamp Screw, Comolded
25 .......AP5014 Decal
26 .......AP1413 7/16" UNF Blanking Plug
27 .......AP1445 O-ring
28 .......AP1410 O-ring, ATX
29 .......AP1487 1/2" UNF Blanking Plug, ATX
30 .......AP1408 3/8" UNF Blanking Plug
31 .......AP1470/S Handwheel 300 bar
32 .......AP1471/S Handwheel Connector
33 .......AP6202 Protective DIN CAP
34 .......AP1472 Conical Filter
Key # .Part # Description Key # .Part # Description
14
89
10
11
26
12 13
29
15
21
24
23
7a
7b
34
13
23
33
23
32
31
34
13
16 13
18
6
5
4
3
2
1
14.7 ft/lbs
20 Nm
70 in/lbs
8 Nm
40 in/lbs
4.5 Nm
40 in/lbs
4.5 Nm

Aqua Lung America
2340 Cousteau Court, Vista CA 92081
760-597-5000
www.aqualung.com
TECHNICAL MAINTENANCE MANUAL
FSR/FST FIRST STAGE REGULATOR
Authorized Technician
Rev. 07/2008
©2008 Apeks Marine Equipment Ltd.