Bleed nipples won't release - any tips?

[Kenny Dave]

Any tips for these little bleeders? I've had the heat gun pointed at them, penetrating oil repeatedly, and they still won't release with as much force as I dare. I've snapped a few in the past, a serial balls up by me.

[vinnyb]

 Never tried it but 50/50 acetone/ATF mix is supposed to be a really effective penetrating oil, it might be worth a try.

[Kenny Dave]

Never tried it but 50/50 acetone/ATF mix is supposed to be a really effective penetrating oil, it might be worth a try.

That's a great general tip on a bit of research. https://www.garagejournal.com/forum/showthread.php?s=53b2f99232bc1b5073cb746773355be5&t=231050&page=2
I have some acetone I think. No ATF though; no transmission. I'll get some, thanks.

[unfazed]

Heat directed to the caliper to the area just below the bleeder is probably your best option. The heat gun would need have a fine point to direct it to the right place.

[Gnasher]

Heat directed to the caliper to the area just below the bleeder is probably your best option. The heat gun would need have a fine point to direct it to the right place.

 


Heat the caliper body below the nipple at the same time, using a ring spanner or break nipple spanner, even a socket start to slowly apply pressure and undo the nipple, you don't need too much.  It's normally does the trick, but not always, sometimes the only way is to drill the bugger out, which isn't always cost effective as a replacement caliper can be cheaper then drilling and helicoiling, certainly quicker. 


Oh if you're doing it while the caliper is still on the bike, make sure you don't heat the break line

[fazersharp]

Heat directed to the caliper to the area just below the bleeder is probably your best option. The heat gun would need have a fine point to direct it to the right place.

 


Heat the caliper body below the nipple at the same time, using a ring spanner or break nipple spanner, even a socket start to slowly apply pressure and undo the nipple, you don't need too much.  It's normally does the trick, but not always, sometimes the only way is to drill the bugger out, which isn't always cost effective as a replacement caliper can be cheaper then drilling and helicoiling, certainly quicker. 


Oh if you're doing it while the caliper is still on the bike, make sure you don't heat the break line

How about sending it to a caliper refurb company and them deal with it. Powerhouse. £57
"Your calipers will be mechanically 'good as new', giving long term peace of mind. (Price includes new pressure seals, dust seals, caliper half seals, bleed nipples, dust covers and a new set of copper banjo washers so you can refit them properly)."

[Kenny Dave]

I'll have a look and see if I've got something to get the heat more localised, thank you. Or maybe buy a part.

I've got acetone and ATF in the post, so I'll try with that too.

If I can't do it then, I'll just have to take it to a garage after lockdown is done.

[Kenny Dave]

I got the b***d.

Not sure what the difference was today, but it wasn't even that hard. Maybe patience and another day to get the pentrating spray in. I don't have an attachment for localising the heat too well, but I did try and aim at the bottom and didn't do it for so long. Previously I was just trying to get everything hot, but is the idea to get the outer hotter than the inner?
Anyway, lots of good tips on this thread so thank you for everyone that helped.

[Trebus]

👍🏻

[celticbiker]

Yes, the idea is for the aluminium to get warm and expand increasing the hole size slightly and the steel to stay relatively cool.

[Kenny Dave]

Thanks.

[fazersharp]

What exactly did you use for heat. Heat gun - is that a paint stripper gun. I only have a plumbing blow torch would that be too fierce   

[celticbiker]

I always use a blow torch, just be careful not to damage paint work with it.

[fazersharp]

I always use a blow torch, just be careful not to damage paint work with it.

Thanks - hope I don't need to use it.

[celticbiker]

Yeh, nipples are always overlooked, I give mine a twist and lube every couple of months and flush and replace the fluid every year.

[fazersharp]

Yeh, nipples are always overlooked, I give mine a twist and lube every couple of months and flush and replace the fluid every year.

I have just been shooting up  Its a penetrating  fluid and I find a syringe and blunt needle perfect. 

[Kenny Dave]

I have just been shooting up  Its a penetrating  fluid and I find a syringe and blunt needle perfect.

I have the exact same needle

[Kenny Dave]

I've had a crazy thought, please talk me out of it. Would it make sense to "paint in" the nipples once they're on? Stop the rust getting in. Copper grease is no good as it gets washed out during bleeding.

[fazersharp]

I've had a crazy thought, please talk me out of it. Would it make sense to "paint in" the nipples once they're on? Stop the rust getting in. Copper grease is no good as it gets washed out during bleeding.

the bleeding  wash out does not affect the thread.