AN fittings have a 37 degree flare. SAE fittings have a 45 degree flare. Can you eyeball the bung and see if it's 45 degrees? Maybe put a square on it with a 45 degree edge if you have one. If it's AN maybe the bung is distorted or something.
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AN fittings have a 37 degree flare. SAE fittings have a 45 degree flare. Can you eyeball the bung and see if it's 45 degrees? Maybe put a square on it with a 45 degree edge if you have one. If it's AN maybe the bung is distorted or something.
I just measured the bung, and it's 37 degrees..so it's an AN bung.
I have to figure out which Fragola fitting this is...as maybe it's not AN 37 degree mating surface?
That doesnt seem possible...as most of their fittings are AN.
But this sucker doesnt seal. It just leaks out slowly, no matter how much I tighten it.
I see a witness mark (or something) on the sealing surface in your first photo. Looks like you maybe have contact only on the outside of the sealing surface, not all the way across. This would be consistent with the welded fitting being 45° and the mating fitting being 37°. Thing is, a 45° male weld bung would be an unusual part to source if you wanted one.
There are sealing washers and "seat saver" tools sold for fixing problems like this. Worst case, cut the fitting off the tank and weld another on.
Do you have another AN hose end of the same size you can try to see if it seals? Maybe the problem is the hose end, not the bung. It also looks to me like there's a line around the bung seat indicating something doesn't fit right.
You guys are both right. There is a seating issue with the fitting. I'm not convinced this fitting is truly an AN flare. So I've ordered another one that IS supposed to be AN flared, and we'll see what happens.
I hope I havent ruined the sealing surface of this weld on AN fitting...
You can buy thin soft copper or aluminum 37 degree sealing washer that should solve your problem. I got mine from an aircraft surplus supplier.
That hose end looks like pipe swivel thread.
Good eye, bigblock, the rest of us missed that. Went back and looked and it's now pretty obvious to me. I think a sealing washer would fix any damage on the weld on bung after getting a proper fitting for the hose.
I disagree. A 1/4" FPT won't fit over an AN6 fitting, and a 3/8" FPT slides right over it. I just tried it and thread sizes aren't even close. That's not a FPT hose end, imo.
I disagree. A 1/4" FPT won't fit over an AN6 fitting, and a 3/8" FPT slides right over it. I just tried it and thread sizes aren't even close. That's not a FPT hose end, imo. Apparently the threads work fine but something is wrong with one of the sealing surfaces.