Freeing a stuck nut - help!

[swee'pea99]

First off, apologies for invading the group with a motorbike issue - but I thought this was probably my best chance of catching the eye of People Who Know..

Long story short, I'm trying to remove one of the hoses that takes brake fluid down to the caliper. It goes into a sort of Y-shaped divider that routes the fluid to both front disks.

I've tried PlusGas, 24 hours, heat (kettle - I'm nervous about using a heat gun, because the hose is rubber or something similar), more PlusGas. I've tried tap-tap-tapping the spanner with a hammer in an attempt to break any bond. I've tried my monster Swedish 14" wrench. But the bugger just will not shift. I'm loathe to apply much more force (I could) for fear of breaking the divider-thingy, which from scraping is I'm pretty sure made of brass. (Is this a real issue? Or will brass stand up to any abuse?) One issue is that the seized bit is higher than the only point where I can dribble the PlusGas, which I'm guessing won't help with penetration.

Plan A is to just carry on with the PlusGas and the overnight soaks, and hope for the best. But if anyone out there has any handy tips or suggestions, I'm all ears. Ta for any such.

 

[vickster]

@keithmac is a motorbike mechanic?

 

[I like Skol]

When you say 'hitting the spanner with a hammer' where exactly are you hitting?
IME the best place to hit the spanner is at the bolt head while applying moderate force to the spanner by hand.

 

[swee'pea99]

When you say 'hitting the spanner with a hammer' where exactly are you hitting?
IME the best place to hit the spanner is at the bolt head while applying moderate force to the spanner by hand.

I'm hitting the far end of the spanner, for maximum leverage. Are you saying you hit the spanner where it meets the nut, while applying force?

 

[keithmac]

Have you got a decent brake line spanner?.

You may have to sacrifice the brake line, if so you could cut the line and get a decent socket and 3/th bar on it.

How old is the rubber line?, service life is notmally quoted at 5 years so you may be trying to save something that's already long past it's best.

Heat would help but you'd have to be careful.

 

[keithmac]

Is it an early Honda?.

 

[I like Skol]

Are you saying you hit the spanner where it meets the nut

Yes, the shock to the threads while you apply the turning force by hand can sometimes be enough to loosen the bolt.

 

[Ian H]

Depending on access, you might be able to support the brass casting with a large adjustable or a pipe wrench.

 

[swee'pea99]

Have you got a decent brake line spanner?.

You may have to sacrifice the brake line, if so you could cut the line and get a decent socket and 3/th bar on it.

How old is the rubber line?, service life is notmally quoted at 5 years so you may be trying to save something that's already long past it's best.

Heat would help but you'd have to be careful.

First off many thanks! Also to @vickster for giving you the heads-up!

Ok, from the top,

I don't know what a brake line spanner is, which I guess answers that question.

It was probably already getting on a bit when I SORNed the bike in July 2014. (Counts on fingers....) Oh. Can I just ask, are these universal/easily available? (I got new fuel hose off the bay for a fiver - be nice if it was like that. ) Do they come with the brass nuts on the ends?

From what you say, I'm minded to have a careful go with the heat gun. I think it was that that freed up the bleed nipple after a similar struggle. What's the worst that can happen? I bugger up a hose that's probably a decade past its best before date...

Thanks again. Oh, and nope. It's one of these...

...as recently saluted hereabouts.

 

[swee'pea99]

Yes, the shock to the threads while you apply the turning force by hand can sometimes be enough to loosen the bolt.

Excellent! Thanks. I shall give that a whack.

Depending on access, you might be able to support the brass casting with a large adjustable or a pipe wrench.

How d'you think I found out it was brass

 

[Ian H]

Excellent! Thanks. I shall give that a whack.



How d'you think I found out it was brass

...and some cloth/a rag to protect it.

 

[keithmac]

Why do you need it off out of interest?.

Motorworks are probably best for BMW spares.

 

[classic33]

Any chance of them being left-handed threads?

 

[swee'pea99]

Success! Hooray! In the end, securing the brass bit properly as per

Depending on access, you might be able to support the brass casting with a large adjustable or a pipe wrench.

proved to be the magic button. I realised that I wasn't applying any real pressure, for fear of damaging the Y-thingy (or its mounting), so I got my mole grips and managed to attach them in such a way that the Y-thingy simply couldn't move at all, then one good heave of the Swedish mega-wrench and bingo! Mark another one up for the CC posse!

Oh, and as for the 'why', I was bleeding the brakes to renew the (at least 8 years old) fluid, but found that nothing came out of the r/h bleed nipple, even when loosened. So I assumed a blockage somewhere between the fluid reservoir & and the caliper and started taking bits off to try and track it down. Looks like I've found it! I've managed to force a 1mm wire through from both ends, to the point where I can now blow through the tube. (I'm guessing the 'tunnel' doesn't need to be massive, given the pressures involved.) So unless anyone thinks otherwise, I'm minded to refit it now and see if I can do the bleeding.

Thanks all.

 

[swee'pea99]

Refitted, bled, and so to bed.

Hooray for CC! Again.