Should we periodically change housing and port o-rings?

Do you guys have a rule of thumb when to change o-rings even when no visible defects are present?

Why ... I guess o-rings can lose elasticity and some other quality without noticeable visual marks that would indicate that, but not 100% sure on what to do.

So, if we assume that t looks good, but is old for let's say 2-3 years ... what to do? In past, with Nikonos this is what I would do exactly ... just to be sure.

Latest after 2 years I change the easy accessible O-rings. O-rings are cheap, so better safe than sorry :-)

If feel that they have lost their softness, then I Change them Prior to that.

I am a lot less stringent about the Housing servicing. I sort of Service it every 2-3 years or so.

/Erik

I just changed my port o-rings on my housing, as I noticed in Lembeh that they were starting to loose a bit of springy-ness and seemed to be a bit long.

These were 3 and 1/2 years old. And were still working fine. Done about 1000-1500 dives in that time.

I've never changed a housing o-ring.

Housing servicing depends on brand. I've never had any of my Subal housings serviced. Other housings I own have needed more regular maintenance. I dive a lot.

Alex

I once worked as an aircraft engineer and changed O-rings on systems that had a very low tolerance for failures of any kind. The systems, hydraulic, oil, fuel...were generally subject to more stress than our housings. Although we would change O-rings according to strict servicing schedules, it was not that frequent (6 months to a year) and only then because we had to dismantle systems for visual inspections. There was a widely-accepted view that if something was working well, you should just leave it alone; there are documented failures as a result of 'over-serving' equipment. And seals need to bed in, after which they are very reliable; the most likely time for a failure is after replacing one. Which is why you should always test the housing minus camera after a service/O-ring changes.

On underwater housings, I keep the seals scrupulously clean, but only ever replace them if they show visible signs of wear or start to harden. Keeping them in a plastic bag and out of sunlight will prolong life. A good test for the larger port and housing O-rings is to very gently stretch them in a few spots around the circumference and look for small cracks appearing at the surface, which indicates excessive wear or a loss of elasticity. I've used housing O-rings for up to 2 years with no problems. And I've spotted potential failures by noticing that loss of elasticity.

In general, keep things clean, visually inspect after each dive trip, keep them bagged up and out of the sun when not in use and replace them only if you see visual signs of wear.

Paul C

i change all the little oring from my Nauticam housing after arround 1000 dives ( a bit more than 2 years ) and they were in perfect condition...don't think i wil do it again .

the port oring and the main oring lost elasticity quite fast, may be 500 to 1000 dive and i had to change it already ( may 2 times in 4/5 years ). tey could have done the job for longer but it started to be difficult to fit the port in the housing.

I think it depends on the materials of the o-ring. For most modern housings that use silicone or fluorosilicone o-rings regular lubrication will keep them soft and "stretchy" and they should have very little compression set. For some of the older housings that use nitrile for main o-rings, even regular lubrication will not prevent a bit of hardening from ozone and sunlight so those I would replace yearly (if you dive a lot).

Bill

Yes, I do! Keep in mind that the o-ring keeps the ocean water away from your $2-4k camera! Don't risk it!

Whatever you do remember to inspect the new oring you are putting on as it might have defects from manufacturing or storage!

I'd echo all of the above. One pretty important issue is proper post-dive rinsing, Ever notice the "griminess" and stickiness of something that has been in salt water, and not rinsed? That's most likely the salt crystals forming (ever seen the piles of salt in Bonaire? - they come from sea-water...). Well, those very salt crystals are pretty angular, and cause undue wear-and-tear on relatively soft things like seals. Worse, they can also "bridge" between the housing seat and the control surface. So a suggestion would be to soak your housing post-dive, and also resist (IMHO) the temptation between dives to see if you got the shot, unless you've had the housing in the rinse tank.

Most of the mfr's also talk about valve seat maintenance. Most suggest the soaking routine, too. As for the main seals, etc., try to store your housing in a cool, dry place, as heat is a big enemy.

As for the main door seals, they simply have to fit. I don't store my housing with the port or door seals installed. I carefully remove them, clean them, then put in a plastic bag. When re-installing, I take a Q-tip swab to the groove, and make sure it's cleaned out. Now with my old eyes, I even take a magnifier to the groove, to make sure I got all the junk out. If you do a lot of muck diving, you'll often have your housing on the sand, and the grooves are really good at picking up sand/dirt in the grooves.