new sink leaking where rigid supply line connects to faucet stem

[OoerictoO]

hi all!
i installed a new half bath. i used the semi rigid supply lines to the pedestal sink because they are exposed and i don't like the look of the braided flexi-lines.

the line is connected to the shutoffs using the supplied brass sleeve and crush/compact nut (not sure what those are called).

the "top" of the supply line, where it connects to the faucet inlet is flared and then tapered back down (kinda like an acorn) such that it seats on the interior slight taper on the faucet inlet (one for cold one for hot). i used the faucet supplied brass nut over the supply line alone to connect to the faucet inlet.

the supply lines look like this:


water leaks around that top nut, out the top of the threads. i've wailed on these things with the flex head basin wrench. i can still budge them if i get just the right leverage, but they seem VERY tight. should i have lubed up the supply line first?

what am i doing wrong?

thanks

[HayZee518]

those fittings you are talking about are called compression fittings. there's an SAE straight thread in the gland and the fitting thread and a compression brass ferrule that goes over the copper line. these compression fittings for some reason are not made standard from one company to another, i.e. parker-hannefin and pfizer. the gland nuts seem to fit at first but bind up when you try to tighten them. you run the risk of cross threading them and messing up the gland and adapter.

[OoerictoO]

thanks for your reply HayZee. yes, compression fittings. mine seem to work fine and my supply lines and valves all came from the same company.

that's not where i'm leaking.

did i need a rubber cone washer or something between the metal supply tube (top part of the drawing above) and the faucet inlet?

i just used the brass nut over the supply line attached to the inlet

[HayZee518]

if your faucet uses a flare fitting from the supply tube to the faucet itself then no washer is necessary. the brass is harder than the copper supply tube and makes a watertight connection when it is tightened securely. if the top of the supply tube looks sort of flat with a bit of copper sticking out then a cone shaped rubber or hard plastic seal goes here. the gland nut is tightened finger tight then another quarter turn with a bsin wrench.

[OoerictoO]

it looked like a flare end.
i posted the picture via a link but this forum won't let me yet because i don't have enough posts.
okay, posted some fake posts below so i could insert the pic above in my original post.

anyway, i've done at least 2 full turns on that brass nut with the bsin wrench and it still drips. i'm sure i've just about crushed that flare by now.

i guess i'll just have to replace those lines and start again?

[OoerictoO]

post 4 so maybe soon i can post that picture

[OoerictoO]

post 5 so maybe soon i can post that picture

[HayZee518]

See if this diagram makes sense to you and get back to me.

[OoerictoO]

i believe that would be the instance you were mentioning with the "sort of flat with a bit of copper sticking out" end. and the grey bits are the (rubber) cone washers?

in my image far above is what my supplies look like. they have what i believe you termed as a flared end (looks kinda like an acorn)

so it sounds like i just use the brass gland nut over the supply and i'm done? and you said hand tight then 1/4 turn more. but i've probably gone two full turns more and it still drips out the top of the nut where the threads are. i could try teflon tape but that's not supposed to be required, no?

[HayZee518]

those acorns are supposed to mate with the inverted flare inside the faucet supply. no lube would be necessary. you usually install those tubes "before" installing the faucet into the sink where you can really "reef" down on them. once they're in the sink its a real "b*****" to get at as you noticed/