Lube O rings on second stage plugs???

[fookisan]

One of my O rings on the LP port plug got ripped when screwing it in and out. Is it good to lude the O ring with Vaseline or anything very lightly or is it a no-no and just keep a bunch of O rings on hand and take them in and out dry?

Thanks,

Dan

 

[DA Aquamaster]

O-rings should always be lubed - it is needed to allow the o-ring to conform to the mating surfaces on the reg and plug without getting torn, stretched, or otherwise stressed.

Silicone lube is readily available, is inexpensive and works for just about any reg as long as the reg is not O2 clean and intended for use with high O2 mixes (over 40%).

For O2 clean applications an O2 compatible lube like cristolube is required.

In a pinch, spit is better than nothing.

When you lube an o-ring, you should put a small amount of the lube on the tip of your fore finger and then rub the o-ring between your fore finger and thumb to work the lube in. When done, the o-ring should be uniformly shiny but should not have any visible amount of lube left on it.

 

[fookisan]

O-rings should always be lubed - it is needed to allow the o-ring to conform to the mating surfaces on the reg and plug without getting torn, stretched, or otherwise stressed.

Silicone lube is readily available, is inexpensive and works for just about any reg as long as the reg is not O2 clean and intended for use with high O2 mixes (over 40%).

For O2 clean applications an O2 compatible lube like cristolube is required.

In a pinch, spit is better than nothing.

When you lube an o-ring, you should put a small amount of the lube on the tip of your fore finger and then rub the o-ring between your fore finger and thumb to work the lube in. When done, the o-ring should be uniformly shiny but should not have any visible amount of lube left on it.

Thanks for the info. Can very small amounts of Vaseline be used? I do not have any silicone grease. Am using air only in tanks.

 

[MarcG]

No. Do not use vaseline. Petroleum based lubricants should not be used in this application.

 

[Divin'Papaw]

Hummm. Here is something I found on the Dive Rite Express website:

How Much and Where to Use Lubricant
Some people very sparingly lubricate the SPG swivel O-ring. Some people also sparingly lubricate the threads of valves before they are installed in the cylinder neck. Do NOT lubricate the neck O-ring itself, and absolutely positively do not lubricate the valve/regulator seal O-ring or DIN threads. Most lubricant is used with dynamic seals in regulators and valves. As a general rule, the O-rings used with static seals in SCUBA applications should not be lubricated at all. The lubricant just causes contamination to stick to the surface of the O-ring and results in more problems with a static seal than any dubious benefit the lubricant might provide.​

(italics are mine)

Looks like they recommend that you DON'T lubricate o-rings used in static seal situations. Wouldn't the hose connected to the 1st stage be a static seal?

Thoughts? Are the correct or are they "all wet"?

 

[Mr Carcharodon]

Thanks for the info. Can very small amounts of Vaseline be used? I do not have any silicone grease. Am using air only in tanks.

Valeline will make neoprene rubber swell so it is best to avoid it. Get some silicone grease and use that, or none at all. The grease makes the seal more tolerant of imperfections in the surfaces it is sealing against. But as stated dirt and corrosion can end up sticking to the grease. That is not really much of a problem for a static seal. I would use some, but keep the film very light.

 

[Hoosier]

Hummm. Here is something I found on the Dive Rite Express website:

How Much and Where to Use Lubricant
Some people very sparingly lubricate the SPG swivel O-ring. Some people also sparingly lubricate the threads of valves before they are installed in the cylinder neck. Do NOT lubricate the neck O-ring itself, and absolutely positively do not lubricate the valve/regulator seal O-ring or DIN threads. Most lubricant is used with dynamic seals in regulators and valves. As a general rule, the O-rings used with static seals in SCUBA applications should not be lubricated at all. The lubricant just causes contamination to stick to the surface of the O-ring and results in more problems with a static seal than any dubious benefit the lubricant might provide.
​

(italics are mine)

Looks like they recommend that you DON'T lubricate o-rings used in static seal situations. Wouldn't the hose connected to the 1st stage be a static seal?

Thoughts? Are the correct or are they "all wet"?

Their alert is all about the exposed area, not internal part. The excessive lube on the tank can pick up all dirty thing in underwater. The o-ring on DIN thread or DIN regulator thread doesn't need any lube. I don't put any lubes on the exposed area except KY on the wrist seal.