Why are all rented BC dump valves broken?

[Thanshin]

I've just bought my first BC, which means I've used rented BCs until now. I've never had or seen a rented BC with any working dump valve. They either do nothing or just allow a useless trickle of air.

Thus, now I have a worry. If people regularly break dump valves, they must be somehow easy to break. I wouldn't like breaking mine.

Therefore, I ask those of you who manage lots of BCs, instructors, DMs etc. How do people break dump valves?

 

[g1138]

Reckless customers and crew? Bad maintenance?

All the rental BC's in my area: LDS's, universities, and all personal BC's have fine working dump valves.
It's the regulators that need constant work. But that's only because certain new divers get's them gunked up in the sand and treats them roughly.

Your gear should last just fine if you treat it with care, and properly rinse it after every salt water and pool water use.
If you're doing a hose rinse make sure to rinse into the dump valve to wash the salt off the spring that's housed in there. Also don't yank too hard on your dump valve, and don't let you buddies do so either during the buddy check.

 

[farsidefan1]

You should quit using the shop with all the broken BCD's. It isn't actually that common a problem. I have never had that issue. And I have not heard of it being an issue with other divers, at least not with any regularity. However congrats on your purchase. Other than fins and mask getting your own bcd is one of the best ideas. You can get used to where the dump valves are so you grab them without having to think about it. Make it automatic as possible. Also you can get your trim adjusted by knowing how high or low to attach the air tank. Happy diving (Regulator next.

 

[Scuba_Noob]

Never had an issue with broken (or even badly functioning) dump valves on rental BCDs. Maybe it's just the shops you frequent. My thinking is that if a shop feels that it's all right to rent out gear with broken parts, I'd consider a new shop.

 

[Thanshin]

It isn't actually that common a problem. I have never had that issue. And I have not heard of it being an issue with other divers, at least not with any regularity.

I have used five diving shops, Spain, Thailand and Mexico. The first time I saw a working valve was in a youtube video a couple of weeks ago (most people use the inflator and/or I never paid attention). The first time I gently pulled a valve "rope" and emptied a BC was when testing mine at the shop.

I might be just unlucky, though. After all, I must have used less than two dozen rented BCs.

Going further in the statistical anomaly, maybe it's because, being tall, I get BCs that were used before me by big strong guys who pulled the valve like trying to rip it away.

However congrats on your purchase. Other than fins and mask getting your own bcd is one of the best ideas. You can get used to where the dump valves are so you grab them without having to think about it. Make it automatic as possible. Also you can get your trim adjusted by knowing how high or low to attach the air tank. Happy diving (Regulator next.

Oh I got the reg too. Where I live, diving equipment in winter gets much cheaper.

I got everything but the cylinder. And the O2 analyzer. And the CO analyzer. And the compressor. And the boat.

 

[Bubbletrubble]

@Thanshin: In my personal experience, the standard, simple pull-dump valves on a BCD are fairly robust. It's the plastic clips that tend to break. Velcro tends to wear out over time. Nowadays gear manufacturers are engineering all kinds of complicated dump valves (e.g., Aqualung Seaquest i3) with different kinds of failure points, so I'm not sure we can say that such new-fangled designs are as robust as the simple old ones.

Pull-dumps can fail in various ways. I've seen the inside spring become rusted out and break. I've seen the string break. Once I saw a very poorly maintained pull-dump that was practically sealed shut by encrusted salt (presumably from saltwater exposure).

Divers should be testing out each and every dump valve on their BCDs during their pre-dive checks. For rental BCDs (and rental regs, for that matter), comprehensive functional testing should be performed on the equipment even before the renter leaves the dive shop with the gear.

The fact that you noticed the dump valves didn't work on your rental BCDs is a good thing.
It sounds like you decided to dive with those malfunctioning rental BCDs anyway.
Perhaps you could have requested to exchange the faulty BCD with one that was fully functional.

From what I've seen, the majority of people who rent BCDs don't check whether all of the dump valves are functioning properly.
Those same people also tend to forget to do comprehensive functional pre-dive checks on their rental regs.
Consequently, reg free-flows and BCD malfunctions are discovered in the water on the first dive of the day (or right before they splash in...when options for gear replacement/repair are limited).
Invariably, those people complain about the rental gear from that shop ("The shop sucks for renting out crappy gear!") and arrive at the conclusion that all rental gear is unsafe.

Basic OW instructors should be spending more time teaching their students how to do gear checks.

 

[Quero]

I've just bought my first BC, which means I've used rented BCs until now. I've never had or seen a rented BC with any working dump valve. They either do nothing or just allow a useless trickle of air.

Thus, now I have a worry. If people regularly break dump valves, they must be somehow easy to break. I wouldn't like breaking mine.

Therefore, I ask those of you who manage lots of BCs, instructors, DMs etc. How do people break dump valves?

Are they really all broken on rental gear? The ones on my rental gear work perfectly. Maybe you need to dive with better ops.... the very cheapest ops will generally have the most "experienced" equipment for rent, and maybe the springs just don't "spring" any longer over time or maybe the valves are not properly cleaned by the dive center staff so that there's crud in them preventing them from opening.

The mechanism of a standard dump valve is very simple. Sand and grit can jam them shut (or open, but this doesn't seem to have been your problem with rental BCs), or they can get "glued" shut by salt buildup. You don't need to worry excessively about breaking your own dump valves--just make sure you clean them properly and they should last many, many years.

 

[Thanshin]

Well, now I feel more secure of being able to keep my valves in functioning order.

I also feel unlucky because I have no doubt that they didn't work. I've specifically been looking for a BC with a bottom valve just to test how it felt to be able to dump air while horizontal.

Well, now I have my own, so no more problems with rental. Other than the cylinders, and I've never had a problem with those.

 

[Colliam7]

I've never had or seen a rented BC with any working dump valve. They either do nothing or just allow a useless trickle of air. . . . Therefore, I ask those of you who manage lots of BCs, instructors, DMs etc. How do people break dump valves?

Like the other respondents, I only infrequently see dysfunctional dump valves on rental, or pool BCDs. (One caveat - because I am associated with a shop in an inland locale, most of our rental gear is used in fresh water quarry diving, not ocean diving),

The problems I do see: a) the ball on the end of the dump line may be missing, after being broken off by a tank landing on top of it. That doesn't mean the dump valve doesn't work, rather you have to make an effort to find the line when you are in the water; b) the shoulder pull dump doesn't work. This is the most common problem I see, and usually results from new divers / students yanking (really hard) on the corrugated hose, and breaking the connection of the wire in the hose to the dump valve; c) dump valves leaking, usually either from some sand / salt / particulate matter affecting the seal of the rubber gasket over the opening, or the dump valve cover coming slightly unscrewed.

As I said, in my experiernce, even these issues are infrequently seen. I see more issue with loose / missing tie-wraps, cracked elbows on the inflator hose, and leaking LPI valves.

In any event, now that you have your own BCD, you shouldn't have issues with the dump valves.

 

[jar546]

There is only 1 reason why the dump valves don't work on the rental gear that you have used:

1) Lack of maintenance and repair by the shop that rents them.

* They are not properly rinsed after each use
* They lack a routine maintenance schedule
* They are not tested after each use

They can't or maybe won't repair them until they know that there is a problem. Since they don't check them or maintain them, they will never know when there is a problem. Rental gear is a low priority for the shop(s) in question