By Dennis Hocker
(March 2011 Entertainment Presentation)
At the March 3 General Meeting, our own lifetime club member Dennis Hocker presented a great useful and entertaining program on taking care of your diving equipment and how (and when) to do some in-field and home repairs. It was very hands-on, with good questions, comments, and experiences related by Dennis and the audience. Dennis’ 40+ years of diving experience and teaching provides a wealth of knowledge to the club, so it was great to have him share this at a meeting. There were a lot of useful “hints” during the program that I’ll try to capture them throughout this report.
Remember that – unlike many other sports (maybe skydiving excepted!) – our dive equipment is life-safety equipment and it should be treated accordingly. It’s also expensive, so getting a few more years out of it by good preventive maintenance is always worthwhile. Also, knowing how to repair a minor problem in the field can also often save a dive.
Dennis began by discussing the best and easiest thing that you can do to avoid problems and extend the life of your equipment: simply give all your gear a very good soaking in fresh water if you’re not going to dive for the next day or two. The salt crystals that form as the water evaporates are sharp and can damage fabrics, plug openings, and cause corrosion of metals. A simple spray rinse will superficially remove the salt, but to really dilute and remove the salt, you need a very good soak for several hours with some agitation a few times. If you’re going to dive within a few hours or the next morning, a good rinse may be adequate since the dive the next day will dilute any salt (if you do not put your gear where it will dry out – like a drying compartment on a boat). But after a long dive trip or if you’re not going to dive for several days, give the gear a good soak, rinse the bladder of the BC, and remove the dust cap from the 1st-stage (keeping it covered can leave enough moisture to cause corrosion). When rinsing the BC bladder, be sure to back-flush the inflator valve to get the salt from that assembly.
If you have booties with zippers, leave the zipper zipped UP after cleaning. Dennis prefers booties without zippers but they are hard to find. Zippers are usually problematic for beach diving that we do locally – with its large-grains that are just the right size for jamming zippers, regulators, and valves. It’s hard to dive with your booties open! .. see note below about a Velcro strap for emergencies when this happens.
Dennis had a great shown & tell discussion on your “Save-A-Dive Kit”, showing his own basic kit and elaborating on more-extensive spare parts for dive trips that are longer or to regions without dive shops. Basic spare parts can go in a small plastic box (middle-left of photo): paraffin (lubricant), a mouthpiece (with small zip ties), silicon grease (O-rings), a “scuba tool” (with all the key tools that SCUBA hardware typically uses), a collection of different size zip ties, a complete set of O-rings (you can buy a small box set of spares at any dive shop), port-plugs for the Low-Pressure (LP) and High-Pressure (HP) outlets of your first-stage, black 10-mil all-purpose tape (not electrical), a small box of ferrules for hose couplings, spare bulbs for your dive light(s). Other useful small tools are TWO small adjustable wrenches to remove couplings from regs (more below), tool-picks an toothbrush for cleaning, a thin guitar pick for removing O-rings, maybe a few long strips of velcro strap to attach items or field-fix that bootie that won’t zip up, etc.
There are other larger spare-parts that won’t fit in a small box, but can be kept in a separate bag. Spare fin straps are very important, but they need to fit the fins that you are using and have the correct snap attachment to the fin; you can buy a spare set at the dive shop. Dennis noted that when removing your fins DO NOT unsnap the fins; instead pull the strap out and off. Unsnapped fins are prone to having the receiver-snap coming loose from the fin and being lost. Keeping the snap in place avoids all this. Many fin straps now have a big loop to more easily grab and to assist in removing your fin straps; or you can buy spring straps that are really excellent (~$40). Also, use your buddy to assist you in donning /removal of your fins and other equipment – it’s easier, safer, and better for your equipment.
A spare LP and HP hose are important spare parts. If possible, include a full regulator assembly (first- and second-stage) or even a complete octopus assembly. If you use a DIN valve, an adapter to a standard yoke valve should be part of your standard equipment. You should be sure to replace your HP hose if you or your buddy notice small bubbles leaking along the length of the hose; this indicates that the metal braid below the black jacket that structurally maintains the pressure is beginning to fail.
Another important spare is the LP BC inflator hose assembly. Both the hose itself can crack and leak (no BC inflation) or the valve can fail to operate (open or closed). You can carry either a spare inflator valve (upper left in photo) or the full assembly (bottom of photo) that is more easily replaced in the field and backs-up both the hose and valve. Dennis noted that are several different types of LP inflator hose couplings, so you need to have the correct type of inflator valve or assembly for your own BC. He reminded us that if the LP inflator leaks or fail OPEN underwater, you can disconnect the LP hose and orally inflate your BC as needed.
A spare mask strap can go into the small box or – even better – bring a spare mask. This is especially important if you have prescription ground lenses in your mask (see Prescription Dive Mask in San Diego). You can also buy removable diopters that stick to the inside of your lenses and can be transferred if needed. Give all the failure modes, a spare mask is best if you can do it. Dennis noted that it’s important to protect your mask when on a boat or other close-quarters diving; most damage occurs when something is inadvertently set on top of the mask.
Other larger spare items: A spare Submersible Pressure Gauge (SPG) is useful. Dennis called the SPG one of the biggest advances in SCUBA diving (remember the old J-valve!). Again, maybe a full SPG & hose assembly is useful. Having spare batteries for your dive computer or other key electronics is important. Dennis reminded us to check for the low-battery indication on your dive computer the night before your dive. However, having a spare dive computer is a good idea; you can wear it as a back-up device on multi-day dives in case your main computer dies – it can save you 24 hours of waiting for your computer to clear! If you’re not going to use your spare computer for long periods, don’t leave the batteries in the computer. Dennis said that most dive computers these days are pretty reliable (versus the early days). A spare dive light is also useful, and can be used as a backup light if you choose the right one (see SCUBA diving, March/April, 2011).
After this great discussion of a spares kit, Dennis talked about home checks and field repairs. He first talked about tank inspections, using a couple of great demo. The Dept Of Transportation (DOT) requires the 5-year hydro, but dive industry has taken in upon itself ($?) to also require an annual visually inspection. You need these to get a fill, so not much you can do about these. Over the past couple a years a few members had found that their tank had lost pressure and had spoiled some dives for them; they had asked Dennis to speak to that. he said that there could be several reasons (valve not tight, burst disk, O-ring leak, etc), but it could also be a “neck leak”. The weakest part of the tank is the neck, and small perforation leaks can occur without failure. He showed one of his demo-tanks with a neck-leak. By spraying a soap/water combination on the neck and first stage, you can often find if the leak is in the valve, O-ring, or neck. The photo shows bubbles coming from the tank neck itself.
Denis next spoke about rapid free-flow of the second stage. Free flow can often occur in the second stage as we giant-stride into the water or from a change of second-stage adjustment (if your unit has one). For the former, just turn the mouthpiece down and it will usually clear. For the latter, adjust the setting adjustment. Sand could also have gotten into the reg, so hitting it against your hand, swishing in the water, and/or breathing heavily through it will often stop the free flow.
If you’re underwater, and your second stage begins a rapid free-flow, the best approach is to use your alternate air source or that of your buddy. In any event, a rapid free-flow UW will likely require an immediate safe ascent to the surface. If alone, you could breath from the air from a rapid free-flowing reg if you need it to get to the surface … but this can also be dangerous – don’t put your lips fully around the mouthpiece; just put it near your mouth, let the air flow in/out of your mouth, and breath slowly.
Occasionally, slow bubbling of the second stage comes from “creep” in the first stage, where the first stage leaks and pressure slowly builds in the LP hose until it exceed the usual 130-160 psi specification and the second stage reg begins to bubble slowly. Dennis demonstrated this using a full reg assembly that had a first-stage with creep. He put the 2nd stage in a small bucket. When the tank valve was turned on, the 2nd stage began to bubble after a short delay indicating that the LP hose pressure had exceed the 2nd stage setting . You can also detect this problems by simply attaching a LP pressure gauge with a hose-coupling adapter (another good thing for a spare/tool kit) to your LP inflator hose. You can then check the LP pressure and look for creep. You should see less than 5 psi creep in the LP hose. if your first stage shows creep it will require service.
Dennis next talked about adjusting the second stage pressure if you don’t already have an adjustment knob on your reg. This can go out of adjustment, also resulting in free-flow or difficult breathing. You need a couple of adjustable wrenches to remove the LP air hose from the reg (see your tool kit). Then you can adjust the spring setting in the fitting by a screwdriver. You can replace the ferrule in the fitting if needed (or dropped or lost) with one from your spare kit.
Finally, Dennis commented about servicing your equipment. His personal view is that your regs and other equipment don’t require an annual service. In fact, regs especially can be prone to damage or mis-adjustment during service, so if you have your reg serviced be sure to mount it on a tank at the dive shop and check all regs for proper breathing, leakage, creep, etc. If you do a service just before that big dive vacation, be sure to check out the equipment by a dive in the ocean or pool before you leave. The old adage applies: “If it ain’t broke, don’t fix it”. However, you should be properly cleaning, soaking, and maintaining your gear as Dennis described up front.
This was a great presentation for new and experienced divers to learn about their equipment, to share problems and solutions that we’ve experienced, and to ask questions. The demos were entertaining and useful. As a club, we’re very fortunate to have such experienced divers and instructors as Dennis, Jim Steele, Neil Benjamin, and others that are willing to share their knowledge with us.
At the meeting, Dennis offered to have members contact him with any equipment or other dive questions that they may have. You can also see Dennis at club dives, at the Board meetings, and the many other events that we have, so you should take advantage of this.
Many thanks to Dennis for taking time to prepare and present this program, and for contributing so much to the club in so many ways.