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bleedin brakes
AlexXtreme - 23/3/16 at 05:27 PM

I thought I knew how to bleed brakes however my latest attempts have got me really fed up... nicer weather is coming soon (I hope) and I want to get the car back on the road...
I have the Eeezibleed kit and have gone through 2 bottles of brake fluid with very little difference after 1 month of trying most weekends!

The front callipers are these
https://picasaweb.google.com/lh/photo/-TubphkxSkuHo5zLY6WC4W-vWs37cn_gW1jg_vRcqYg?feat=directlink
they are 4 potters with external tubing connecting one side to the other and I think this could be the issue (I have just re-built them with new seals etc)

I have std new Sierra callipers at the back

I tried taking off the front calliper from the mounting and positioning it so the bleed nipple is at the top with no difference.

At the back I had a loop in pipe up to the calliper that could have caused an airlock unbolted the calliper to straighten out this with still not luck
https://picasaweb.google.com/lh/photo/k_n1hfGO-LW9VVWeGmgyL2-vWs37cn_gW1jg_vRcqYg?feat=directlink

If I pump the brake peddle I can just about feel some brake pressure - other than that it feels like it there is some serious air in the system

Any idea welcome
Alex

[Edited on 23/3/16 by AlexXtreme]


joneh - 23/3/16 at 05:32 PM

What master cylinder are you using?


rash12 - 23/3/16 at 05:39 PM

not sure what flexy pipes you have but if possible clamp them up on at a time then try the pedal to find out where the problem is ?


AlexXtreme - 23/3/16 at 05:44 PM

They are braided pipes so I can not clamp them...

The master cylinders are as follows
https://picasaweb.google.com/lh/photo/y3RqXy3TBXJqSA710OUwGG-vWs37cn_gW1jg_vRcqYg?feat=directlink
and I have not touched them


joneh - 23/3/16 at 06:04 PM

If it's dual circuit I'd expect at least one side to firm up, could the cylinders be sucking air in as well as fluid? Is the filler flexihose airtight?


steve m - 23/3/16 at 06:58 PM

We do need to know which master cylinder you have, as it makes a difference

my old system with an escort m/c was easy to bleed, but when I opted for floor mounted OBP system, it was awful, and showed the same problems you are having , and about the same amount of brake fluid !

however a call to OBP, and sent the both m/c's back, and new ones sent back to me, all in about 3 days,
bled the system, and never had a problem since

cant fault OBP for there service

steve


britishtrident - 23/3/16 at 07:34 PM

You will to unbolt your front Princess callipers to get the nipple at the top before bleeding.


AlexXtreme - 23/3/16 at 10:40 PM

Thanks for the suggestions!

The system is pressurized with the eezibleed at 15psi so I can not be drawing air in to the system with the master cylinders

link of the master cylinders pic added above - good point on one side should be firm.. perhaps I have air in both systems

I have unbolted the princess calipers to put the bleed nipple at the top and no difference...


Brian R - 24/3/16 at 10:50 AM

You could try back bleeding it. I remember having to do an old Rover clutch using that method. I connected a tube from the front brake to the clutch slave, opened both bleed nipples and pumped the brake pedal. Worked a treat.

You could use a donor vehicle parked next to your car and try the same technique. I'm sure there are hand held kits that do the same though.


Slimy38 - 24/3/16 at 11:06 AM

quote:
Originally posted by AlexXtreme
Thanks for the suggestions!

The system is pressurized with the eezibleed at 15psi so I can not be drawing air in to the system with the master cylinders

link of the master cylinders pic added above - good point on one side should be firm.. perhaps I have air in both systems

I have unbolted the princess calipers to put the bleed nipple at the top and no difference...


Might be worth trying a lower pressure, I tend to do eezibleed with no more than 5 psi. At 15 psi I'm surprised the brake fluid isn't spurting out of the nipple!!


AlexXtreme - 24/3/16 at 12:29 PM

I will have a think how I can back bleed it.... it does sound like an option!

Even under 15psi the fluid does not come out very fast for some reason..???


Mr Whippy - 24/3/16 at 12:53 PM

quote:
Originally posted by AlexXtreme
I will have a think how I can back bleed it.... it does sound like an option!

Even under 15psi the fluid does not come out very fast for some reason..???


at 15psi it should be horsing out. Are you sure you have the right bleed screws, check they aren't blocked and that they do uncover the hole to vent the fluid. If so then there may be something wrong with the master cylinder seals or the pistons inside. At 15psi I expect to fill a cup in about 8 seconds.

[Edited on 24/3/16 by Mr Whippy]


mcerd1 - 24/3/16 at 01:51 PM

What about something stupid like a kink in a brake line?

You could crack open joints at various places to try and find where the restriction is (obviously this could be very messy! )


AlexXtreme - 24/3/16 at 02:12 PM

I dont think there are any kinks as I have not touched the lines.... but thinking about it, perhaps there could be a blockage and will check....

Cracking open the lines would be a last resort due to the mess (as you say ;-) )

Alex


madteg - 24/3/16 at 06:07 PM

You will have to move rear calipers so the bleed nipple is at the top. It took me adges to sort mine out. You have a air pocket in the caliper that cannot escape.


rusty nuts - 24/3/16 at 07:21 PM

If the fluid is slow coming out of the bleed nipple it may be because you don't have any slack in the master cylinder push rods? Might be worth cracking off the brake pipe Union on the master cylinders whilst you have the Easibleed on , that way you'll know if there's any blockage in the system


AlexXtreme - 25/3/16 at 09:31 AM

Thanks for the suggestion... will try again over the (wet) weekend and report back


AlexXtreme - 29/3/16 at 11:42 AM

All sorted.... thanks for the suggestions / help.

The comment on the callipers mentioning that they were off the Princess was useful. Mine have a spacer to allow them to be used with vented discs and this complicated the bleeding... In the end I released the interconnecting pipe as well as all the bleed nipples whilst under the eezibleed pressure (with a tray to catch the mess) and this seemed to clear the air from the system.
Well it does feel that this is the case anyway :-) - not yet tried them on the road with the poor weather

Cheers
Alex