View previous topic :: View next topic |
Author |
Message |
waynedear
Joined: 16 Apr 2017 Posts: 21 Location: Liverpool
|
Posted: Sun May 07, 2017 8:47 am Post subject: Lots of air in front brake |
|
|
I have just replaced the front lines with stainless and rebuilt the back.
The abs for the back bled perfectly as did the caliper.
Now onto the front, bled at the abs pump until fluid ran clear BUT I AM STILL GETTING LOTS OF AIR BUBBLES, now as the new fluid is coming out of the pump there should be no air bubbles, master cylinder to hard pipe is tight.
Do you think I am getting air through the master cylinder piston and seals.
I have stripped this, when I loosened the screw for the piston it all shot out on its own, is that a sign of worn seals or normal ??
The bore is immaculate, clean and unmarked.
The bike is a K1100lt 1993 abs 2
Many thanks
Wayne _________________ K1100lt 93 |
|
Back to top |
|
|
N41EF Flying Brick Rider
Joined: 23 Mar 2014 Posts: 406 Location: Aiken, SC
|
Posted: Sun May 07, 2017 6:51 pm Post subject: |
|
|
How are you bleeding it? I used a mighty vac to suck at the nipple and gently squeezed and released the lever. Make sure the lines are tight, and make sure you keep the tiny meter cylinder full. It's almost a two person job. Did you put the cover back on? I know if you pump and release the lever you'll get squirting back into he front master cylinder, that's the vent function. _________________ 2014 R1200RT Water Cooled
2001 R1100S Light
1993 K1100LT. Nissan Ice Blue.(Gone) |
|
Back to top |
|
|
waynedear
Joined: 16 Apr 2017 Posts: 21 Location: Liverpool
|
Posted: Sun May 07, 2017 7:24 pm Post subject: |
|
|
N41EF wrote: | How are you bleeding it? I used a mighty vac to suck at the nipple and gently squeezed and released the lever. Make sure the lines are tight, and make sure you keep the tiny meter cylinder full. It's almost a two person job. Did you put the cover back on? I know if you pump and release the lever you'll get squirting back into he front master cylinder, that's the vent function. |
Manually, I am very good at it, lines are tight and I use a cloth cover to catch the spurts, I am going to fit a set of new seals in master cylinder _________________ K1100lt 93 |
|
Back to top |
|
|
Grunter Flying Brick Rider
Joined: 30 Sep 2015 Posts: 367 Location: North East England
|
Posted: Mon May 08, 2017 6:54 pm Post subject: Air Bubbles |
|
|
I have always found that when bleeding and cannot get rid of all the bubbles I wind a type of tape around the threaded part of the bleed nipple, the sort used by plumbers to seal compression joints.
In UK it is called PTFE tape, very thin and usually white. It will seal threads against the ingress of air. If you can find some where you are, Remove the nipple and wind no more than 2 thicknesses around the threaded part of the nipple then screw it back into the calliper. Bleed as normal.
Once the brake is bled you can just leave the tape on the nipple and tighten it as normal . _________________ 1997 K1100LT
1994 R1100RS |
|
Back to top |
|
|
SugarHillCTD Site Admin
Joined: 10 Oct 2007 Posts: 4240 Location: Now in Eastern Pennsylvania
|
Posted: Mon May 08, 2017 7:54 pm Post subject: |
|
|
Nice hint there Grunter. Thanks. _________________ John & Cathy
'92 K100RS4V Pearl White SOLD
'04 K1200GT
IBA Several-SS1k, BBG, 50CC NYC to S.F. |
|
Back to top |
|
|
waynedear
Joined: 16 Apr 2017 Posts: 21 Location: Liverpool
|
Posted: Tue May 09, 2017 3:22 am Post subject: Re: Air Bubbles |
|
|
Grunter wrote: | I have always found that when bleeding and cannot get rid of all the bubbles I wind a type of tape around the threaded part of the bleed nipple, the sort used by plumbers to seal compression joints.
In UK it is called PTFE tape, very thin and usually white. It will seal threads against the ingress of air. If you can find some where you are, Remove the nipple and wind no more than 2 thicknesses around the threaded part of the nipple then screw it back into the calliper. Bleed as normal.
Once the brake is bled you can just leave the tape on the nipple and tighten it as normal . |
I shall remember that, thanks. _________________ K1100lt 93 |
|
Back to top |
|
|
Corkboy Mad Brick Rider
Joined: 26 Aug 2013 Posts: 81 Location: Cork, Ireland
|
Posted: Tue May 09, 2017 1:49 pm Post subject: |
|
|
Also, I pressurise the system by clamping the lever overnight. This compresses all the remaining air bubbles and helps them to float to the highest part of the system, hopefully the reservoir. When you unclamp the leaver, there should be one big bubble floating up. _________________ '08 K1200GT
'87 K100RS 0140995 (Gone)
'97 K1100LT 0188024 (Gone)
'08 Transalp 700 (Gone) |
|
Back to top |
|
|
waynedear
Joined: 16 Apr 2017 Posts: 21 Location: Liverpool
|
Posted: Tue May 09, 2017 2:07 pm Post subject: |
|
|
Corkboy wrote: | Also, I pressurise the system by clamping the lever overnight. This compresses all the remaining air bubbles and helps them to float to the highest part of the system, hopefully the reservoir. When you unclamp the leaver, there should be one big bubble floating up. |
First thing I did, made it worse. _________________ K1100lt 93 |
|
Back to top |
|
|
Grunter Flying Brick Rider
Joined: 30 Sep 2015 Posts: 367 Location: North East England
|
Posted: Wed May 10, 2017 4:55 am Post subject: Re: Air Bubbles |
|
|
Grunter wrote: | I have always found that when bleeding and cannot get rid of all the bubbles I wind a type of tape around the threaded part of the bleed nipple, the sort used by plumbers to seal compression joints.
In UK it is called PTFE tape, very thin and usually white. It will seal threads against the ingress of air. If you can find some where you are, Remove the nipple and wind no more than 2 thicknesses around the threaded part of the nipple then screw it back into the calliper. Bleed as normal.
Once the brake is bled you can just leave the tape on the nipple and tighten it as normal . |
I should have added, make sure the tape does not block the exit holes for the expelled fluid. _________________ 1997 K1100LT
1994 R1100RS |
|
Back to top |
|
|
waynedear
Joined: 16 Apr 2017 Posts: 21 Location: Liverpool
|
Posted: Thu May 11, 2017 3:23 pm Post subject: |
|
|
New master cylinder repair kit fitted, bled perfectly
Went for a spin on a dirty alley, no one told me you had to reset the abs
Learnt how, be done tomorrow _________________ K1100lt 93 |
|
Back to top |
|
|
|