Quick question about line fittings adaptation
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Last edited by mrvedit; Jan 23, 2026 at 02:16 PM. Reason: clarity
This is the earlier fitting https://a.co/d/hj0smse
But what he wants to use is this type but with correct threads for the late 60 case https://ebay.us/m/fVB2VI
I am not sure such an animal is made .
Hard lines are typically 5/16 inverted flare
I don't know of any off the shelf options
Best option would be to re-tap the case for 1/4 NPT
The NPT will be loose to start but as the taper grows it will eventually start cutting the case.
Then you can just run a standard 1/4NPT to 5/16 inverted flare
Your other option would be to get a "6ORB to 1/4 NPT Female" which is 9/16-18 thread on the ORB side (o-ring boss) and then of course 1/4NPT female to use to adapt to your inverted flare.
Another option would be to cut off the inverted flare and add a nut and ferrule and re-flare the line to 37 degree JIC and then just use a normal JIC aka AN fitting adapter in the case







