Bleeding Bleeding Brakes

[richhemmings]

Hi All,

This may seem very trivial, but I'm having some problems bleeding my brake lines.
Followed Mr. Haynes to the letter, but there's zero fluid coming through. I checked all unions and they seem sound, took the master cylinder banjo off and pumped the brake and fluid was coming out OK, checked the calliper ends and no fluid is pushed through, needless to say the lines were empty when installed, is this just a massive airlock, and how am I going to resolve? Tried a pump on the bleed nipples to draw the fluid through, but no joy and the only tool I have to push the fluid through only fits on screw-top reservoirs.

Hints, Tips, etc much appreciated.

Cheers in advance,

Rich

[Username]

Just undo the bleed nipples and take the reservoir cap off and the fluid will come out, got something do with gravity Then just bleed as normal. Never takes me more than five minutes.

[veefer400]

Use a 100ml syringe & push the fluid back up through the calipers into the master cylinders - I'll try & find a link I posted earlier...

Air bubbles will always go up, trying to push them down the line is tedoius, to say the least...

[veefer400]

Try this:

viewtopic.php?f=28&t=23119

[richhemmings]

Just undo the bleed nipples and take the reservoir cap off and the fluid will come out, got something do with gravity Then just bleed as normal. Never takes me more than five minutes.

Lol... really?
bviously tried this, but gravity doesnt seem to work in my area! cap off, nipples...

...oh, wait a min... both? or one at a time?


...carrying on, if I undo one, nothing happens...

surely with one undone, that line should flow with fluid?
I must be being a total prat guys, this is like the simplist job... still not done :p

[Cammo]

I always bleed the master cylinder first before the calipers.

Air can be trapped in there (it's the highest point in the sealed system) which prevents fluid from reaching the calipers.

If your m/c doesn't have a bleed nipple just pump the lever then crack the banjo bolt to let air out and nip it back up. Do this until no visible air comes out. Tie a rag around the banjo bolt and lines so fluid doesn't go everywhere.

Once this is done move on to the calipers.

[richhemmings]

update...

Tried the gravity thing... no joy, although I did bag the top banjo on each line and let fluid run down the lines through the callipers and out of the nipple to prove there was no blockage.

Bled the master cylinder, but had not effect.

Also tried to draw fluid out using a 20ml syringe with no joy, think this may be partially due to a crappy syringe (not large enough to go over the nipple) or the drain pipe (again, not great union).

Used a pump to draw fluid out, and this worked partially, the old chap has an antique vacuum pump, so now... I'm thinking a proper vacuum pump, or perhaps a pressure bleed?
Does anyone know where I can buy/borrow/steal a pressure bleed kit or a vacuum pump from? My friendly (car) mechanic has a set of screw top pressure kits... unfortunately no good as my reservoir is not !


Rich

[lukemillar]

My 2p:

A lot of the guys on the Triumph site recommend these:

http://www.speedbleeder.com/

I have always been skeptical, figuring you just need to learn the proper technique for bleeding brakes and that is what I have stuck with. However, in the end I cracked and thought I would try them out.

They are great! Initially bought them for my 675, but the NC30 has the same spec bleed nipples so I put them on those calipers when I rebuilt them.

[richhemmings]

Job Done!

Put a stronger vacuum on the nipples and drew about 2 reservoirs of fluid through and then bled as per normal.
Rear ones to follow...


Cheers for all the suggestions guys!