Sun Dec 27, 2009 10:51 pm
This procedure assumes that you know how to rebuild a 2 stage Aqualung, and that you possess the minimum amount of tools to do so. I make no claims, warranties, or promises that you will not damage your equipment or kill yourself, so following these procedures implies that you do so at your own risk.
Required materials:
-Original DA "Aqualung" parts breakdown (available in download section).
-Custom springs, second stage, quantity of 2.
-Micrometer.
-Magnahelic or manometer.
-Compressed air tank, containing about 500 PSI of air.
-A first stage nozzle with NO creep.
Procedure:
Once your regulator is as disassembled as you prefer, remove the hinge pin securing the two second stage screws (index #23). Remove both hinge screws (index# 22) and inspect for wear in hinge pin holes. Replace if at all worn. Remove horseshoe (index# 21) and both springs (index #20). Set aside springs in a bag, and label them to prevent mixing them in with your new springs.
Install new custom springs. You will notice that they have a lower spring rate then the stock ones. This is a good thing. Install both springs (#20), position horseshoe lever in place over springs (#21), and screw both screws in all the way (#22). If the screws are bottomed out and they are not aligned, then use your screwdriver to align them. Now, turn each screw out 1.5 turns.
Take your hinge pin (#23) and compare it to a known straight edge. Both ends of the pin must be straight where they penetrate the screws of the second stage. If this is not the case, then make it so using needle nose pliers.
Install your hinge pin (#23) through the second stage screws (#22), but do NOT bend the pin yet. Using the micrometer, take a measurement of the distance between the horseshoe lever (at the screw) on both sides. The distance between the horseshoe lever and the body should be about .080 inches ON BOTH SIDES. If this is not the case, then adjust each screw alternately a half turn at a time until this is so. Once the screws are set correctly, then you can bend the hinge pin (#23) to secure it to the screws. Ensure that once the hinge pin is bent that both sides of the lever are still at .080 inches. If you bent the hinge pin (#23) too far, then bend it back a little bit to ensure that the distance between the horseshoe lever and body are as close to .080 inches as possible.
Assemble the rest of the regulator if you have not already done so. The regulator should be fully assembled, with the top can and diaphragm removed.
Place the regulator on the tank as specified in the required materials. Charge the regulator. Adjust the first stage until the second stages begins to barely hiss air, then back it off 1/8-1/4 of a turn. Turn the air off, and purge the regulator. Charge the regulator again and operate it several times. It should not leak from the second stage. Wiggle the horseshoe lever from side to side (without actuating it), it should hiss when you do this, but just barely.
Finish assembling your regulator to a ready to dive state. Ensure that your diaphragm ears are bent at such an angle to most efficiently contact the horseshoe lever. This is more important on these regulators than it is on the aquamaster as the lever sits much lower in the can.
Place your fully assembled regulator on the tank as specified in the required materials. Charge the regulator. Place the mouthpiece in your mouth, and snake the inlet tube of your magnahelic in your mouth without the magnahelic mouthpiece installed. Using your lips as a seal, draw a breathe on your DA series regulator with the supply pressure at about 500 PSI and the magnehelic tube in your mouth. The regulator should begin to crack at .8" of water as indicated on the magnahelic. If this is not the case, then increase or decrease intermediate pressure as required to achieve this state.
Enjoy your regulator, because now it does not breath like an iron lung. You will hear a clicking sound on inhalation. That is the sound of the diaphragm traveling downward and contacting the horseshoe lever, as it sits lower in the can than an aquamaster. This is normal.
The impossible missions are the only ones which succeed. -JYC