Hello,

Seems that there is a leak from a supply line hose under Bathroom basin. Need to loosen the bolt that connects hose to faucet.

What's the ideal/recommended method to loosen this bolt. Read somewhere that WD-40 is not to be used for this.

Thanks,

I have never used anything but the proper tools and leverage under the sink. Maybe your set up makes it harder but it's doable. If this video doesn't help then please let me know.

https://www.bing.com/videos/search?q=basin+wrench+video&view=detail&mid=85B68A4F1B4CCDA6050D85B68A4F1B4CCDA6050D&FORM=VIRE

That was a rather strange question. Your answer was spot on.

Afraid, basin wrench wasn't doing anything.

Someone has suggested elsewhere to use a lubricant specifically for plumbing nuts, not wd-40 but something else.

Will take a look at that.

RIDGID EZ Change Faucet Tool-56988 - The Home Depot (https://www.homedepot.com/p/RIDGID-EZ-Change-Faucet-Tool-56988/303528759)

NK, I think I'm starting to see your problem. You are talking about where your supply line attaches under the sink itself, so it's difficult to get to. Does that sound right? If so, can you remove the sink? I just installed a new faucet in a similar situation. I took the sink off and found it all a MUCH easier undertaking. Removing the sink was easy in my situation, but might not be possible in yours. If that is the case, might be able to get vice grip pliers on the nut and tap the pliers some with a hammer. These are not typically difficult to get off since they don't require much tightening to seal to begin with. I suspect someone in the past really cranked down on the nut to get it to stop leaking. I wouldn't heat it unless you are ready to put on a new faucet. Too much plastic around it.

Tal did have an interesting idea. Cut the supply line and see if you can get a socket wrench on it.

You might also try putting the basin wrench on the nut, and then using vice grips to turn the basin wrench. You can get more leverage that way.

I've never heard of a lubricant especially for plumbing fixtures. If you can find it, then here's to hoping it works. You are a patient man!! I'd have had a fit by now.

One more thought, though I hate to say it. Make sure you are turning the nut in the right direction. Lying under a sink looking up, it's easy to get your bearings off center.

One way or the other, please let us know how it turns out.

I edited my response to reflect your specific job which isn't a bolt but a hose fitting correct? Vice grips should do it.