Amendments and approval of this document can only be carried out by the relevant people listed on the Approved list of signatures, which is listed in the Apeks Quality Manual. To instigate a change, a Task / Change request form, (Form No.
Apeks or Aqualung to speak directly with cleaning procedure. a Technical Advisor before proceeding any further.
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Remove O ring (6) from valve diaphragm housing (7) using O ring removal tool AT79 Unscrew the 4 mouthpiece screws (5) using the 5/64” allen key. Disassembly of the GX300 Regulator Case is Now Complete...
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GX300 Regulator Maintenance Manual Disassembly Procedures for the Valve Using the protruding arms of the spindle locking washer (22) pull the whole side valve shuttle assembly from the Spindle Assembly side valve spindle (15). Remove Nylock nut (27) using 7mm nut driver or spanner and put to one side.
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GX300 Regulator Maintenance Manual Unscrew nyloc nut (27) and dispose of, then slide the Remove O ring (18) spindle bush (23) and spindle locking washer (22) free from valve shuttle (17). from the side valve shuttle (17). Remove silicone seat (16) from valve shuttle (17).
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GX300 Regulator Maintenance Manual Disassembly Procedures for the Valve Push on the underside of the diaphragm ring (32) to reveal the diaphragm (30). Peel the diaphragm Diaphragm (30) at one edge to reveal the groove which it was seated in and work free all the way around until the diaphragm ring (32) is free.
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GX300 Regulator Maintenance Manual Carefully push on retaining ring (35) to diaphragm Assembly Procedures for the Valve (30). Ensure the eight teeth on the retaining ring Diaphragm Assembly (35) are facing towards the diaphragm (30). They must also fit between the four stop lugs of the diaphragm (30) but not go past or over them.
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GX300 Regulator Maintenance Manual NOTE: Lubricate valve shuttle (17) shaft only. Do not Assembly Procedures for the GX300 lubricate threads or silicone valve seat end. Inlet Valve Place the silicone valve seat (16) on a clean flat surface face down. Press the valve shuttle (17) onto the seal until its fully located into place.
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The ‘7 hole’ setting is the optimum setting for normal a preliminary setting diving operations. For further adjustment see page 11. only Fit O ring (12) onto Assembly of the GX300 Inlet Valve is Now spindle bush (23). Complete Assembly Procedures for the GX300 Regulator Case...
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Assembly of the GX300 Regulator Case Regulator Adjustment is Now Complete is Now Complete See Page 12 for Optional Magnehelic Regulator Adjustment is Now Required...
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10) is the optimum setting for normal diving operations. button to ensure all At this setting the regulator will function correctly within parts are operational a wide range of regulated supply pressures (see GX300 and have free Regulated Supply Pressure Guidelines on page 15). movement.
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5. Fit the 3 new cap head screws (10), tighten each screw using a 5/32” allen key to 5Nm (44 in.lb). Final Installation of the GX300 Regulator is Now Complete Caution: Do not overtighten as this may damage the cover...
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NOTE: When retro fitting the new GX300 regulator to an existing G2000SS helmet it will then be known as the Aqualung G3000SS helmet. A double exhaust kit (water dump), PN 400111, should be fitted to the helmet at the same time.
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Apeks Quick Disconnect Hose -AP0205/Y, into the second port of the G3000SS Helmet d. Apeks Switch Block - AP0281/G, connected to the other end of the QD hose via the bail out port e. One of Apeks First Stage Regulators: i.
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Main surface MP gas supply, using surface gas control panel and standard diver’s umbilical, connected directly into one port of the G3000SS Helmet c. Apeks Quick Disconnect Hose -AP0205/Y, from the first stage regulator to the second port of the G3000SS Helmet d. One of Apeks First Stage Regulators: i.
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GX300 Regulator Maintenance Manual Table 1 - Troubleshooting Guide SYMPTOM POSSIBLE CAUSE TREATMENT Leakage from 1. Excessively high supply pressure. 1. Ensure supply pressure is below the regulator maximum stated within the pressure exhaust ports. guidelines. 2. Supply pressure is above the standard 2.
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GX300 Regulator Maintenance Manual SYMPTON POSSIBLE CAUSE TREATMENT Excessive 1. Low supply pressure. 1. Check equipment upstream. work of 2. Lever (25) set too low. 2. Adjust lever. breathing. 3. Interruption in supply to the 3. Check for leaks. Check the supply hoses are regulator.
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GX300 Regulator Maintenance Manual Table 2 - Recommended Tool List PART NO. DESCRIPTION APPLICATION AT33 3/4” Spanner Side Valve Lock Nut (1) AT51/L Slotted Valve adjustment Tool Valve Seat (13) AT88 Seal Expander O Ring (18+19) AT79 O Ring Tool...
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GX300 Regulator Maintenance Manual Cleaning and Lubrication Procedure Cleaning Brass and Stainless Steel Parts If required, pre-clean in warm, soapy water* using a nylon bristle tooth brush. Thoroughly clean parts in an ultrasonic cleaner filled with a solution of household white distilled vinegar (Acetic Acid) mixed with fresh water (max 50% vinegar).
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GX300 Regulator Maintenance Manual Table 3 - Recommended Lubricants & Cleaners LUBRICANT / CLEANER APPLICATION SOURCE Christo-Lube MCG-111 All O ring seals Lubrication Technologies ® (Lubricant). 310 Morton Street Jackson, OH 45640, USA (800) 477-8704, or Apeks Marine Equipment Ltd...
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GX300 Regulator Maintenance Manual Table 4 - Torque Specifications PART NUMBER DESCRIPTION / KEY NUMBER TORQUE AP2502 Lock Nut 5 Nm (44 in.lb) A2 Stainless Steel Socket Head Cap Screw UNC AP2512 5 Nm (44 in.lb) 12-24 x 0.375 A2 Stainless Steel Socket Countersunk Screw UNC AP2510 0.5 Nm (4 in.lb)
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