Aqua Lung MRS III, Operation And Maintenance

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MRS III MAINTENANCE
Scheduled Service (1-year and 5-year)
9.0 AFTER 1 YEAR, AND EVERY YEAR THEREAFTER....
9.1. PARTS REQUIRED:
1-year overhaul kit ( Part Number MRSKIT1).
9.2. Open the Supply Cylinder valves (VAL1) and then slowly vent all air from the MRS III thru
one of the fill hoses (HOS1).
9.2.1. WARNING — AIM THE HOSES AWAY FROM YOURSELF AND FROM ANY
OTHER PERSONNEL. HIGH PRESSURE AIR COMING INTO CONTACT WITH
THE SKIN IS DANGEROUS. ALSO, ESCAPING AIR CAN CAUSE A LOUD NOISE.
9.3. Replace all seals in the SEA fill adapter (PRS21). See figure 14. This consists of three
O-rings, two (PRS21-3) and one (PRS21-6), and two back-up rings (PRS21-2).
9.3.1. The first O-ring (PRS21-6) is the one that makes the seal to the SEA. This is a normal
wear item and can be replaced anytime. The tools required are an O-ring pick and the
PRS21-8-3 (figure 15).
9.4. To replace the other parts will require
a set of external snap-ring pliers, an O-ring
pick, the PRS21-8 , and some non-toxic O-ring
lubricant (Christo-lube).
9.5. To start, remove the visible O-ring
(PRS21-6). Then using the snap-ring pliers
remove the snap-ring (PRS21-5) and set it aside.
Grasp the hex knob (PRS21-1) in one hand and
hold the body (PRS21-4) in the other. Pull apart
with a slight rotating motion of the hex knob.
Use the O-ring pick to remove the O-rings and
back-up rings.
9.5.1. NOTE THE ORDER THAT THE PARTS
ARE ON THE SHAFT: STARTING
FROM THE HEX KNOB — BACK-UP
RING (PRS21-2); O-RING (PRS21-3);
O-RING(PRS21-3); BACK-UP RING
(PRS21-2); SNAP-RING (PRS21-5);
O-RING (PRS21-6). See figure 14.
9.6. Clean the parts with a soft clean cloth to remove
all of the old lubricant. Inspect parts for
damage. If any is found replace the assembly.
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NOTE: PRS21-8 (103384) comes as a
complete set; not available separately.
PRS21-4
PRS21-2
PRS21-3
PRS21-1
PRS21-2
PRS21-3 PRS21-5
PRS21-6
PRS21-8-3
PRS21-8-1
PRS21-8-2
figure 15
figure 14