Quick question: How do I disconnect my second stage?

[diverdowndude]

Chrystal lube is the best if you intend to take them apart frequently. A small tube will last for years. Use it very sparinly.

 

[ScubaSarus]

Chrystal lube is the best if you intend to take them apart frequently. A small tube will last for years. Use it very sparinly.

Exactly! you put just enough lube on to make the o-ring shiny. You should not see any lube on the o-ring after its been lubed.

 

[knotical]

So how tight is right? Several folks have cautioned against over-tightening, which is good advice, but a bit vague for some of us engineers.

Manufacturers' recommendations vary, but are typically in the 30 – 40 inch-pound range.

I've seen as low as 15 in-lb recommended for a port plug and as high as 125 ( ! ) for a hose, but a key point is that they are all in inch-pounds, not foot-pounds.

If you don't have access to a torque wrench, consider that the typical open-end wrench that fits these hoses is about 6-8 inches long. If you use about 5 pounds of force on the end of the wrench, you'll be in the ball park.

 

[cooperscuba]

Shear cutters work well for disconnecting but it`s a bugger to reconnect afterwards.

 

[divad]

To avoid cross-threading when replacing the second stage, hold the first stage with the open port facing down, hold the hose near the thread with the second stage dangling, and spin it in by hand. It should go in effortlessly. If it doesn't, you're cross-threading it.

 

[siikik]

LP hoses are usually 9/16 and HP 5/8, although some are different.

Yes... different indeed... I have an octo that is 19/32. Go figure. But it's amazing I actually had a wrench that size!



Ken

 

[themagni]

I just did this myself prior to my last dive, and it was easy.

I used a cheapo adjustable crescent wrench to start the hoses, then used my precision biocalipers to remove them all the way. I switched the backup second stage and whip, tightened both with the biocalipers, and then used the same wrench to tighten to about the same torque as they were previously.

The final step is to put your regs on your tank and make sure your handiwork doesn't leak.

The wrench I used wasn't right. I'd have liked a skinnier, smaller one like the non-adjustable style but I simply don't own one. I will probably pick up a set or a smaller adjustable wrench expressly for diving.

Funnily enough, there was a missing o-ring on my whip. I replaced it and did not get the normal wet patch on my chest after the dive.

 

[Teamcasa]

Yes... different indeed... I have an octo that is 19/32. Go figure. But it's amazing I actually had a wrench that size!

Some fittings are metric sizes.

19/32 is a shade larger than 15MM

 

[Doc]

Some fittings are metric sizes
19/32 is a shade larger than 15MM

You call .00320" a "shade" ?

The right tool for the job:
..............................

I've spun hoses off with two flat rocks, once I used a P-38 can opener.

Don't overthink this. A precise open ended wrench is lovely and very much so preferable, a pliers will work.

 

[Teamcasa]

You call .00320" a "shade" ?

A precise open ended wrench is lovely and very much so preferable, a pliers will work.

Yep.

Maybe this wrench will fit after the pliers treatment.

Or the fallback to all sizes. The blue wrench!

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