Olympus O-ring grease vs generic pure silicone grease

[Gilligan]

I spoke with Jason Bradley, a professional photographer at Backscatter.com regarding Olympus PT-010 main O-ring grease.

He stated the main O-ring is made of silicone rubber and therefore pure silicone grease cannot be used on it. The O-ring will absorb the grease and it will break it down resulting in the O-ring stretching.

Jason went on to explain the Olympus grease is not pure silicone grease. The Olympus tube states "SILICONE GREASE, ONLY FOR SILICONE RUBBER O RINGS". This does not mean the grease is silicone grease but instead means it is grease for silicone O-rings. He said the O-ring grease for the blue Sea & Sea O-rings is okay to use on Olympus O-rings because the Sea & Sea O-ring is also silicone rubber and their grease is compatible.

I have 64 dives on my current PT-010 with the original O-ring. It shows no signs of stretching. I use only the Olympus grease on the main O-ring.

I got about 50 dives on my older PT-010 before the O-ring stretched out to the point it would not stay in the groove and had to be changed. I used generic pure silicone grease on those O-rings

Does this all make sense!

Any O-ring experts want to reply?

 

[ReyeR]

Does this all make sense!

Yup, perfect sense. Perhaps one for the Tips & Techniques section or something.
I've done 100+ dives over 18 months since I got my PT-015 and the o-rings are still fine. I always use the Olympus grease for them.

 

[jcclink]

Did he say what the magic grease really was? Is it part silicon or petroleum based? Petroleum based greases will also have a similar negative effect on the o-rings, but at a slower rate. If used, use very sparingly. A lot depends on how often the o-rings are removed & greased. The more frequently this is done, the shorter the life of the o-ring. More grease, more absorption & more elongation (stretching). I prefer to use just water as a lubricant. I've gotten a couple hundred dives on my video housing, which also uses a silicon main o-ring, with virtually no stretching of the o-ring. (& no leaks)
If we would just go back to old fashioned buna-N o-rings (the black ones) we wouldn't have to worry about the pretty colors & what type of grease to use (or not use). Cheap generic silicon grease on everything. I recently replaced the blue o-rings on my S&S strobes with buna-N (approved by the S&S repair facility). Since I now have a Tetra housing for my 5050, which uses buna-N, life is much easier again.

 

[TRIG]

Did he say what the magic grease really was? Is it part silicon or petroleum based? Petroleum based greases will also have a similar negative effect on the o-rings, but at a slower rate. If used, use very sparingly. A lot depends on how often the o-rings are removed & greased. The more frequently this is done, the shorter the life of the o-ring. More grease, more absorption & more elongation (stretching). I prefer to use just water as a lubricant. I've gotten a couple hundred dives on my video housing, which also uses a silicon main o-ring, with virtually no stretching of the o-ring. (& no leaks)

Hello jcclink, are you saying that you don`t use any grease at all, that you have good
results using just " fresh" water?

TRIG

 

[jcclink]

Thats right - silicon o-rings only thou. My last 2 video housings have used silicon rings. Never ever greased them. Just keep em clean. I run a wet finger over the seal just before I close the housings. No problems. Gates manual says do not grease. I only remove them if necessary to clean properly, & after a major dive trip. I'm probably doing 150-200 dives/yr.