<p>As a generalization of service intervals, I would agree with cbmech2 in that not everyone has their BC serviced every year. As a service tech, I
do service my BCD every year but that's just because I've seen too many problems out there. Here are some things that you should check regularly.
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<p>1) First, the biggest problems that I have seen are having to do with poor internal rinsing. The worst case that I have seen personally was to remove about a quarter cup of salt crystals from inside of a BCD bladder . The salt crystals are very large and sharp (looked like very course rock salt with the largest crystals being greater than 3/8 inch in length), tend to accumulate at the bottom of the bladder where there is normally a seem. You pack your BCD for a trip and apply some pressure to this area and start cutting into the bladder wall. If you puncture the bladder near the seam, the BCD bladder is done. You can legitimately patch some BCD's if the puncture is at least 1 inch from a manufacturing seam and not larger than 1/2 in length(Oceanic). They make a BCD patch kit and procedure for their BCD's only, and only there kit should be used. The moral to this is to be sure to thoroughly rinse the inside of the bladder until the drained water is fresh.</p>
<p>2) The inflator and low pressure inflator hose are areas that also require attention. Most of the newer BCD's have more plastic internal parts than metal and are
slightly more tolerant than the older ones with more plated brass parts. The older power inflators with higher metal parts content are especially sensitive to corrosion due to residual salt. If you do NOT rinse the inflator well and you are not diving very regularly, some of the water evaporates with time and the concentration of salt increases and vigorously attacks any plated parts. The result is some level of chrome loss. This loss provides a foothold for the salt to attach the next time and so forth. I've seen power inflators that had to be repeatedly soaked in hot fresh water just to break the salt loose enough to disassemble. The parts cost is often high enough to result in removal from service for economic reasons. Be especially wary of used BCD's that you do not know the history of. They could look great on the outside and be terrible internally. The newer BCD's with less metal are often using a schrader type valve core for regulation of the air flow. This is not the same ones that you get at the auto parts store. The are manufactured from materials that stand up to the operating conditions in a BCD. They fail very quickly, and sometime cause other parts to fail as well (as in corroded to the point that they can't be removed and the part that holds the valve needs to be replaced as well.)</p>
<p>3) Finally there is the lowly and usually ignored LP inflator hose. These need to be rinsed thoroughly, inspected and lubricated. Rinse it by submerging in fresh water, inspect for damage (nicked O-ring) or corrosion (white powder between the sliding sleeve and the core and/or around the detent balls). Lubricate with a light bodied spray silicone. First indicators as to problems around the corner is hard to get on or off, visible chrome loss, stream of air bubbles when diving.</p>
<p>4) Check the dump valves. When you do your air test, fill the BCD via the power inflator part way and pull the oral inflator and hose to actuate the shoulder dump. Be sure that it reseats properly. Pop the back dump and verify that it opens and reseat properly. Next inflate the BCD with the power inflator modulating the inflate button to verify that the BCD fills both slowly and quickly - and most importantly smoothly. Fill the BCD until the back or shoulder valve relieves and then quickly pop that valve to reduce the pressure in the BCD to just below the cracking pressure for that valve. When I service a reg, I usually service the BCD first so that I can check it again for loss of pressure when the reg is serviced, usually 2+ hours later. The BCD should still be hard at the end of the test. Personally I leave mine over night and check them the next day, but a couple hours should suffice.</p>
<p>Lastly, bring you BCD in to get "factory trained" service at least every couple of years. If you keep it really clean and check it as outlined above several times a year or more, you will probably be OK. If something doesn't seem right, get it in to be serviced early so that you won't be disappointed by service lead time issues and your chances of failure due to performance issues will be reduced. If you can afford it or if you dive frequently, get it serviced professionally yearly. I hope that this will be helpful.</p>
