O-Ring in / out - the Olympus' official position

[djanni]

I called support and ask for their official position on the question.

It is:

If the housing is to be stored for 30 days or more remove all o-rings. Apply Olympus o-ring grease and place into a sealable plastic bag and store in a dark place.

Should have listened to Jim in the first place.

 

[Gilligan]

I have always stored my O-ring out of the housing and in a small zip-lock bag regardless of the period of time involved.

The irony of tech support telling you that is the housing originally comes with the main O-ring in its groove with the housing locked. Who knows how long it sat that way from the factory to the consumer.

Go figure.

 

[Footslogger]

Yeah ...with or without tech support advice it just made sense to me over the years that constant pressure on the O-ring would shorten it's useful life. Been removing ALL external O-rings, applying generous silicone grease and storing them in small zip locks for years, going back to my Nikonos days.

Knock on wood ...have not had an O-ring failure in over 25 years of diving.

Probably shouldn't have made that last statement !!!

'Slogger

 

[djanni]

Yeah ...with or without tech support advice it just made sense to me over the years that constant pressure on the O-ring would shorten it's useful life. Been removing ALL external O-rings, applying generous silicone grease and storing them in small zip locks for years, going back to my Nikonos days.

Knock on wood ...have not had an O-ring failure in over 25 years of diving.

Probably shouldn't have made that last statement !!!

'Slogger

In a previous thread on this subject someone mentioned Oylmpus' practive of boxing the housing with the o-rings in place and latched down and that what caused me to wonder. I can imagine an o-ring in there without grease and under pressure for a year or more.

I think the Oylmpus Tech read that to me from his support system. That's why I referred to it as their offical position.

It is a contridiction. Go figure.

 

[Charlie59]

Dude, you can take out the o-ring?

 

[ScubaJorgen]

Dude, you can take out the o-ring?

Umh.... You're not serious, are you? :huh:

In case you are: you should take it out and clean it after every dive....

I take the o-ring out after every dive and store it in the housing itself.

I recently took out *all* the o-rings, you know, of the knobs. They collected quite an amount of dirt through the years (I've got my house since 2001). I cleaned the rings and sockets, put on new grease, and reassembled. Stuff is working fine again. Warning: if you want to try this at home, be sure you have some technical skills. If you're equiped with 2 left hands, please don't


BTW: I've got a PT-010, C3000 (RIP), C4000 and C4040. I am still using the original O-ring

 

[aquaagua]

I called support and ask for their official position on the question.

It is:

If the housing is to be stored for 30 days or more remove all o-rings. Apply Olympus o-ring grease and place into a sealable plastic bag and store in a dark place.

Should have listened to Jim in the first place.

Good to know, I better do it now. I had a really hard time finding the PT 018 housing and now I have to try to find some new o-rings so I have extra sitting around (in silicone grease and a plastic bag). Thanks

 

[ScubaJorgen]

In a previous thread on this subject someone mentioned Oylmpus' practive of boxing the housing with the o-rings in place and latched down and that what caused me to wonder. I can imagine an o-ring in there without grease and under pressure for a year or more.

I think the Oylmpus Tech read that to me from his support system. That's why I referred to it as their offical position.

It is a contridiction. Go figure.

All materials, even the elastic ones, show a phenomenon called 'kruip' (in Dutch, don't know the Englisch term). This means when pressure or force is excerted for long periods of time the material deforms permanently (=non elastic). Elastic materials normally deform when force is applied, but deformation springs back when force is removed. With 'kruip' the deformation is permanent. For O-rings this means they get flat sides and loose their function. Of course what is regarded as 'long periods' depends on the material. For chewing gum it is very short, for o-rings it may take years. Polymers show 'kruip'.

Given this process, I always store the O-ring outside the housing. Besides, you have to get it out after each dive to clean.

Another process is aging. The material deteriorates over time. I once took apart a valve of my cylinder (manufactured in 1987, say it was 15 years old by the time I took it appart). O-ring were brittle and showed cracks. Applying pressure to the material speeds up this process. I gues UV (sunlight) speeds up as well. Maybe oxidation (reaction with oxygen) plays a role too. By applying grease, this process is slowed down. Note: grease has no function with respect to the sealing effect of the o-ring!! I would like to put it stronger: if you apply to much grease it has the opposite effect.

So the official statement of Oly to take it out, grease it and put in a place where the sun never shines ;-) sounds plausible...