Gas line leak, need connection advice

[svenness]

This is a new keezer build. Using 5/16" ID red gas hose and swivel nuts. Tried both an oetiker clamp and a worm clamp. Getting a strong leak even at 10psi out the hose at this connection. I'm using the piece recommended on the kegconnection website:
"Our 1/4" Flare to 5/16 Tubing (FFL to Barb) Swivel Nut is used to connect hose 5/16 hose to 1/4 treaded FFL Cornelius Keg disconnects."

It is fairly snug, but doesn't require heating of the tubing like with 3/16" beer line and a 1/4" barb.

What am I missing? Is there some well known trick to get a seal that I am unaware of?

Thanks in advance for your help HBT.

 

[day_trippr]

When using a swivel nut and barb set to connect to a valve (such as the shut-off valve on a regulator output or on a manifold) or common metal fittings (elbows, tees, etc) you need one of these nylon flare gaskets inside the connection:

You do not need the gasket when using the swivel nut and barb to connect to most plastic quick disconnects on the keg end of the line as the disconnects come with an integrated gasket...

Cheers!

 

[zachattack]

Also make sure you go just a hair past finger tight. It's very easy to crack the washers but you do need it to be snug.