Rounded flare nut on hard line

[Lord E38]

Trying to replace the hose on my E46 and in my wisdom I have rounded off the nut at the top. I used a proper 11mm flare nut wrench and let it soak overnight with penetrating oil. No joy with mole grips either. Haven't tried heat yet but I have a blowtorch in the post.

Forgive the stupid question (I've only had to do pads before) but what else can I try, and what should I do if I truly can't get it off? Thanks.

[Ritchie335is]

Those flare nut wrenches are a waste of time, they just splay out.
Personally I d try decent vice grips again, but make sure that the teeth are decent and you get them on tight enough, if you don t burst a blood vessel in your eye when squeezing them on, they re not tight enough.
A gentle heat will also help.
It will come out you just need to approach it the right way.

[steveo3002]

vice grips as tight as you can , or its looking a bit scabby replace the pipe or a section of it

i used to round them off all the time , then invested in some snap on flare nut spanners and theyre way better at not wrecking stuff

[rOB.bOb]

Since you're replacing the hose, apply heat and then the flare nut spanner will work. The brake fluid does boil locally so make sure to disconnect the other end of the hose first, or cut the hose.
Worst case, cut the copper pipe just above the nut, put a new nut on and flare.

[lufbramatt]

Looks like the original steel pipe? Which is a bit harder to flare properly.

On my e39 I ended up replacing all the hard lines with cunifer… the steel stuff was all on its last legs and started to split once you put any strain on it with mole grips etc.

[ROTELLA]

I bought one of these Russian wrenches a few years ago & it's never failed:

Removing the clamping bolt means you can slip it over the pipe then replace & tighten.
No fear of rounding off the nut.

Was a few £ on Ebay but can't see any now.
Russian name is -
Ключ разрезной для тормозных трубок с винтом для зажима 7 x 11 мм

[Ritchie335is]

That looks like a good tool!

[DaveF-SkinnysAutos]

Heat, heat and then some heat.

[E-bmw]

Personally, due to the state of the hard line, perhaps you should just cut it off & replace the hard line anyway.

[steveo3002]

if youre likley to ever work on a used car again , get a roll of kunifer pipe and the flaring tool then you can laugh at this sort thing and knock up a new pipe in minutes , doesn't cost a massive amount either

and a snap on brand spanner is by the best at getting these undone

Edited by steveo3002 on Friday 23 October 11:21

[GreenV8S]

ROTELLA said:

I bought one of these Russian wrenches a few years ago & it's never failed:

I haven't seen those before - they look like a great idea.

[TwinKam]

It's all about the tools...
A crows foot wrench with a breaker bar is way superior to a flare nut spanner, but I do like the look of that Russian spanner!

Equally, the correct type of water-pump plier is superior to a Mole wrench, as it self tightens with the undoing pressure. Knipex Aligators are fantastic, they don't twist sideways because the hinge is supported on both sides, and have directional teeth, the harder you push, the more they bite.

Edited by TwinKam on Friday 23 October 13:07

[stevieturbo]

Vise Grips make a tool that is solid for nuts if you have room. Available in different sizes

https://www.youtube.com/shorts/5a5ZsFJraLo

Although regular vise grips should do well too.

https://www.ebay.co.uk/itm/183347022355

Gland pliers like the Knipex above are also very good as they tighten as you pull harder. I'd go for the Cobra with the locking pivot though

https://www.knipex.com/en-uk/products/pipe-wrenche...

Again available in different sizes.

[redbulletv8]

Parrot nose jaw grips work well too. Agree that the pipe requies replacing though.