brake bleeding

[Benandsally]

Hi All,
I need help,,,
I am in need of a Brake Mechanic who knows brakes on 71.
I have replaced the front two calipers and pads, well do you think i can bleed this sucker.
I have used a vacuum bleeder and have tried to bleed  them manually, still no peddle.
Has any one else experianced this and or does any body know someone out Liverpool way or close i can show this to or get to repair for me ?
Thanks again...
    :mad:

[demonx]

If you didn't pinch the line with some vice grips or something similar and heaps of air has got in then it could take quite some time to bleed it all out.

When doing mine I went through two bottles of fluid till I got a good pedal. That was with all four calipers off and all four lines pinched. Does that sound familiar or are you well beyond that much fluid?

[Benandsally]

Hi Demonx,
No i didn't pinch any lines with vice grips whilst bleeding just vacuum sucked and then manual bleeding ( pump and hold ).I did go through 2 and a half bottles of fluid.I did this proceedure three times, all to no avail.
Even whilst bleeding manually i had the vacuum on as not to let any air return.
Thanks

[demonx]

I didn't mean pinch when bleeding, I meant during removing calipers etc. I always lock something on the hose before I un do the caliper, that way you massively reduce the air entereing the system. You stiull have to bleed but not as much as if you didn't lock the line.

I've never used a vacuum or anything to bleed, always just done it the old school way, one person in the car pumping the pedal, the other person working the nipples.

A few questions just to problem solve (I'll also ask the dumb questions just in case, I know I've done stupid things before):

Why did you replace the calipers? If the brakes were soft maybe it was not the calipers and could be the master cylinder or hoses?
Are all the nipples in place? Are
Are you bleeding the top nipples?
What condition are the hoses in - even if they look perfect are they bulging?
Are there any leaks that you can see - including dripping down inside the wheel rim and not getting as far as the floor?

Thats about all I can think of straight away...

[Benandsally]

demonx
NO questions sound dumb especially when i cannot figure it out and yes i have came under the stupid catorgy a few times so keep them problem solving questions coming.
OK no i didnt pinch the line because i undone it at where  hard line joins soft line on inner guard.
I replaced the 2 front calipers because they were leaking on the disc and were part seazed with a lot of corrosion.Nipples are in place and am bleeding top nipples. Lines are in good condition and are not buldging in any way.
Yes i had the leaking on the inside but that was dripping from the disc re; leaking calipers
Thanks heaps

[craigh]

When I rebuilt my rear  calipers (leaking fluid like yours) I had the lines disconnected on and off  while i did the work.

I  put a cap on when I could to stop draining system.

Replaced the soft lines with braided hoses etc as well.

Took over a bottle of fluid to get them firm again.

I installed speed bleeders on mine as well that made it a bit easier but just followed the process of bleed in the order of (for rear) inside first then outside.

I think the idea is to bleed the nearest point to the master cylinder first then work outwards to get rid of air.

Look here as well on the US forum:

http://forums.corvetteforum.com/c3-tech-performance/2278849-bleeding-the-breaks-info-please.html

When I did mine  I put the details here but does not cover bleeding order.

http://www.australiancorvettes.com/phpBB/viewtopic.php?t=6326&postdays=0&postorder=asc&start=60

[Scott]

I think the idea is to bleed the nearest point to the master cylinder first then work outwards to get rid of air.

I thought it was the opposite, start at the furtherest point and work back.  That's how I did mine.  Putting a long clear tube on the bleed nipple helped too.

I bled mine by gravity. Crack the nipple and wait. If nothing happens, a few pushed of the pedal help things along. Elevate teh clear tube above the caliper and watch. When no more bubbles come out, it's done.  Uses much less fluid too.

[Benandsally]

Hi demonx, craigh

I thought you start from the furtherest point to thats how i did mine then when demonx said start at the closest i thought thats why they didnt work plus i did not bleed rear with inside and outside i just thought that if you bleed the highest nipple.
Two and a half bottles of brake fluid later still scrathing my head.
I will have to start again with all my new input
thanks heap guys

[craigh]

I think the idea is to bleed the nearest point to the master cylinder first then work outwards to get rid of air.

I thought it was the opposite, start at the furtherest point and work back.  That's how I did mine.  Putting a long clear tube on the bleed nipple helped too.

I bled mine by gravity. Crack the nipple and wait. If nothing happens, a few pushed of the pedal help things along. Elevate teh clear tube above the caliper and watch. When no more bubbles come out, it's done.  Uses much less fluid too.

I was referring to the inner and outer of a rear caliper.  Am getting confused now but I thought i did the inner then outer bleeds on the rears.

This is also a great read...does not seem to  think order matters at all.

http://forums.corvetteforum.com/c3-tech-performance/2278849-bleeding-the-breaks-info-please.html

[sirfixalot]

Sounds like front reservoir has drained out fluid & has an air lock. Elevate car so master cylinder outlet is at highest point to pass air out of master cylinder  

[72vet]

Sounds like front reservoir has drained out fluid & has an air lock. Elevate car so master cylinder outlet is at highest point to pass air out of master cylinder  

If what Sirfixalot suggested doesn't work, you may have to bench bleed your Master Cylinder.

The Pic below might help

[77CVT]

You'd be unlucky for the master cyl to need bleeding but is a possibilty.  Word on the street is bleed furtherest point from the master cyl first and work in (personally I don't think it matters).

Check the line to the caliper is tight and be prepared to use gravity........takes a lot longer bt sometimes necessary with C3's.  On my old one I had to leave it bleed overnight!

Frustrating I know!

[th693]

bleed brakes from furthest wheel first. sounds like if youve let the system run dry without pinching the hoses the master cylinder has air trapped in it and will need to be bled before you bleed the wheels