Second Stage Disassembly. Aqua Lung SEA MK

17. Remove and discard the fill adapter port o-ring (22).

9

22. Using the bottle vice (pn 100397), vice insert (pn 100398) or strap wrench (pn 54325A22), hold the cylinder secure. While holding the cylinder secure, unscrew the first stage body (36) from the cylinder using a 1 3/16" crowfoot & flex handle drive.

18. Using your fingers, peel the cap protector (29) off the first stage.

23. Remove and discard the o-ring (37) from the cylinder threads.

19. Insert the pins of an adjustable spanner wrench into corresponding holes in the top of the piston cap (30).

Second Stage Disassembly

1. Using small wire cutters, carefully snip the plastic mouthpiece clamp (55) and remove the mouthpiece (58) from the box bottom (54). Inspect the mouthpiece to ensure it is free of any tears or cuts that may cause leakage of water into the second stage or other discomfort. Discard the mouthpiece or set it aside to be reused, depending on its condition.

20. Unscrew the piston cap from the first stage body. Separate the piston (32) from the cap. Remove the spring (35) from the first stage.

2. Using your fingers, unscrew the front cover assembly (40

& 41) from the box bottom (54).

21. Remove and discard the o-rings (31 & 33) from the piston.

Insert the pin of the seat extraction tool (pn 109437) down the bore of the piston and press out and discard the HP seat (34).

31

33 34

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3. Lift out the Ring Cover Support (42) and diaphragm (43).

Inspect the diaphragm for any tears or pin holes by holding it up to a light and gently stretching around the perimeter. Discard the diaphragm or set it aside to be reused, depending on its condition.

SEA MK Technical Maintenance Manual

7. Remove and discard the exhaust valve (56) by grasping the flap of each valve and pulling straight outward.

4. While depressing the lever (45), unscrew the inlet fitting (52) using a 3/4" wrench. Remove and discard the inlet fitting o-ring (14).

inlet fitting

5. Gently grasp the lever and remove the entire valve assembly (44-51) from the box bottom. It may be necessary to push in on the valve assembly through the inlet hole.

CAUTION: Valve assembly parts are under spring pressure. When removing the locknut (44), be sure to keep the poppet side of the valve assembly against the work surface or place a finger over the poppet to prevent the parts from ejecting from the valve body.

8. Hold the valve assembly, poppet side facing down, firmly against the work surface. Using a 1/4" nutdriver, remove and discard the locknut (44). Separate the locknut (44), washer (46), lever (45), poppet (50), and spring (49) from the valve body (47).

Using the threaded end of the poppet, press the poppet bearing

(48) out of the valve body from the outside to the inside.

50

49

47

45

46

44

6. The exhaust cover (57) is held in place by four tabs: One side has two short tabs (usually on top), and the other side has two longer tabs (usually on bottom). The two longer tabs come all the way through until flush with the box bottom; the shorter tabs are recessed. The exhaust cover is removed by popping out the short tabs. To do this, use your index and middle fingers to press downward on the center rib, toward the long tabs, while simultaneously pulling out on the exhaust cover.

9. Using the tip of the o-ring removal tool, or any type of pointed tip type tool, pierce the center of the low pressure seat (51) and remove it from the poppet. DO NOT discard the seat, as it will be used later to aid in reassembly.

THIS ENDS DISASSEMBLy

Before starting reassembly, perform parts cleaning and lubrication in accordance with

Procedure A: Cleaning and Lubricating

(p. 25).