I was able to get a carbon fiber 4500 psi tank. The Valve has been removed to Inspect. How do you torque your Valves back on? I'd like to set it at 75 ft lbs.
It is an isi tank.
It is an isi tank.
how to torque scba valve
- Thread starter mc357
- Start date
75 ft lbs sounds high I've never torqued the just get them as tight as I can by hand or if there is a spot for a wrench then as tight as I can with a wrench and a rubber strap or a leather belt in a vise with something thick between the vise and tank so it doesn't damage cf tank
Upvote 0
I worked in a dive shop for ten years. I was a trained and certified scuba and scba inspector. Valves with O ring seal are screwed in until they stop and that’s it. If you want to tighten it just a touch more it’s not a problem. The gas pressure will make the valve so tight it won’t unscrew without a wrench.
Gas cylinders that have tapered threads are a different matter, they are tightened with a wrench similar to torque like you would tighten gas lines or water lines with tapered threads.
Randy
Gas cylinders that have tapered threads are a different matter, they are tightened with a wrench similar to torque like you would tighten gas lines or water lines with tapered threads.
Randy
Upvote 0
I have a SCBA and SCUBA setup as well. I cracked it open to inspect it once in a while for moisture. Make sure you use some silicon grease or o-ring safe grease on the o-ring when setting the valve. I just hand tight it. the seal design with o-ring should take care of the seal. Fill the tank and check for leaks with some soapy water,
If it leaks, I would check the O-ring for pinching. i had to replace my Scuba tank o-ring because it old and shrunk.
75 ft/lbs is not unreasonable for the thread size. Good luck finding an open end wrench that measure torque.
If it leaks, I would check the O-ring for pinching. i had to replace my Scuba tank o-ring because it old and shrunk.
75 ft/lbs is not unreasonable for the thread size. Good luck finding an open end wrench that measure torque.
Upvote 0
Hand tight and a bit is good enough. Any tighter and you may NEVER be able to remove it. Why you ask? How do you secure the tank while applying counterforce? I have used a fork on a forklift and a cargo strap successfully in the past, but not everybody has a forklift!
Upvote 0
The only purpose of torquing any fastener is to stretch it like a spring so that it won't loosen. Your valve seals with an o-ring and does not require any torque to stay in place. Tighten the valve by hand until it stops against the shoulder and that's all that 's required. No sealer, no oil just turn it until it stops and you're done.
Upvote 0
I agree, no Teflon tape, sealer or any petroleum base oil or grease. I still stand by adding some lubricant to help the o-ring slide in easier. You can use Super Lube that is readily available at Harbor Freight and it is silicon base grease. I Used that stuff on all types of oring including breach seal. I am talking about adding just a sheen not a blob.
Upvote 0
I ended up using silicone grease, the kkind I use on water filter o rings. Pure silicone grease just a small amount after I cleaned the threads really well.
Upvote 0
Great discussion, thanks for the various bits of info. I would have overlooked the silicone grease probably.
Upvote 0
I never found this old thread when I was searching for how to remove an SCBA valve. Good find. When removing the valve assembly, a firm blow on the wrench handle with a heavy plastic / dead blow mallet should do the trick. I was able to remove two valves on 10+ year old tanks with a wrench and a deadblow hammer. I was able to get the valves broken free with no need to secure the tank other than knee pressure on it on the floor and thanks to the advice from Scotty1 in this thread of mine. Just make sure you get the lefty loosey part down before you strike the wrench. You may need to remove the hanging bracket and / or the burst disk to get the wrench on the flats depending on the model. One of these $17 wrenches from Amazon comes in handy if you don't have an open end or or adjustable wrench that fits your valve.
Last edited:
Upvote 0
Crows foot wrench on a torque wrench may be the best option or this link.
www.amazon.com/VANPO-Adjustable-27-1-21-8-Interchangeable-Pipeline/dp/B0BR3NKLSZ
www.amazon.com/VANPO-Adjustable-27-1-21-8-Interchangeable-Pipeline/dp/B0BR3NKLSZ
Last edited:
Upvote 0
Agreed that o-ring fittings don't need to be torqued to seal properly. In other uses implement crows foot at 90 degrees to the torque wrench to get an accurate torque spec as opposed to paralle with the body of the wrench. This is how AR15 barrel nuts are torqued that require a crows foot.
Upvote 0