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65 brakes

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LUCKY13

Guest
I have 4 new Delco Morraine calipers, a new 9" booster and a newly rebuilt power brake master cylinder by Whitepost Restorations but the brakes on my 65 just don't feel right. I have bled them until no air can be seen during bleeding but my pedal travel is still too much. What am I missing?
 

IH2LOSE

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May 24, 2001
Messages
3,908
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We Will All Meet Again
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1966,and a 1962 thats almost complete
Do they feel good and firm and its just too much pedal travel?

Or is it just soft and spongy to the floor.

did you change the pads also
 
L

LUCKY13

Guest
I did change the pads with the calipers. The feel of the pedal is pretty normal but there is too much travel. Master cylinder stays full so no leaks.
 

Kid_Again

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Jul 6, 2004
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NJ - Which exit you from?
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65 SB Roadster, 66 BB Coupe
if you can pump the brake pedal a few times and get a solid feel, then it's the seals on the master cylinder (I assume that you see no brake fluid leaking around the calipers)...


if not, then you need to replace your brake hoses - how old are they?


BTW, did you bench bleed the MC before putting it back on? If not, then you have air entrapped in the MC piston and you will never get a solid pedal. You bench bleed an MC by putting it in a vise, add a fitting to the front with a rubber return line going into the reservoir (clamp it into place so it stays steady), fill the reservoir 3/4 full with the hose 'way below the fluid level and then push the MC in and out with a 3/8" socket extension......once the bubbles disappear, you're done, cap the front and install the MC...any minor amounts of air you get in the line after the bench bleed will work its way out
 
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LUCKY13

Guest
I did bench bleed the master cylinder and remember, I just got it back from Whitepost. All four brake lines are new also. Maybe I need to bleed the master cylinder again. :W
 

Sting Ray

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Feb 8, 2001
Messages
481
Location
Upstate NY
Corvette
1967 Red Convertible
John,

Where did you get thoose fittings?
I had my M/C rebuilt by White Post 2 years ago, last spring when I went to put it back in, there was blowby, so don't assume yours is 100% perfect. Although I haven't returned it to Billy to get it fixed yet, bought a repro.

Tom M
 
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LUCKY13

Guest
I spent the evening bleeding the brakes again. I started by bench bleeding the master cylinder per JohnZ's method. This went smoothly. I then bled each caliper and bled both sides of the rears. I test drove the car again and the pedal travel is still too much. The pedal feels solid, not spongy. I guess I need to call Whitepost and ask them if they feel its possible for the master cylinder to be the problem. ;help (even though they just rebuilt it)
 
L

LUCKY13

Guest
I backed the 65 out of the garage this morning. To my surprise, it had zero brakes and the maste cylinder is still full. I'm removing the m.c. today and sending it back to Whitepost. I guess I've found my problem.:bash
 
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LUCKY13

Guest
One last thing, during the m.c. bleed process last night, fluid ran out the front brake line connection port when I connected/disconnected the bleed line fitting. The back (rear) connection port would not leak a drop of fluid when the bleeder was installed or removed.
 

Kid_Again

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NJ - Which exit you from?
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you found your problem

...this is heresy to some but i let NO ONE rebuild parts that my life depends on...so, i do my own mc honing and put in the seals myself...i did the same with my brakes and yes, i've made mistakes but when i do a rebuild i just go around the block, granny driving and assess the situation....

...i compteley understand with anyone who disagrees with me but, in my experience, ss sleeves are pure bull**** and a way for somebody else to make money off of me when i can do just as good a job, and most often times, better... a simple light hone cleans up the bores JUST fine

JMHO
 
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LUCKY13

Guest
I tried two times to rebuild the m.c. but honing would not seal the bore. It was too worn and needed more severe corrective action. The new sleeve should have done the job but apparently, it didn't. I'll respond back after I ship and receive the m.c. from Whitepost again.
 
Joined
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7,246
Location
Washington, Michigan
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'67 Marina Blue Convertible
...i compteley understand with anyone who disagrees with me but, in my experience, ss sleeves are pure bull**** and a way for somebody else to make money off of me when i can do just as good a job, and most often times, better... a simple light hone cleans up the bores JUST fine

JMHO

That's true if a simple light hone will clean the bore up perfectly, but if it has pits or scratches and requires more honing than that, it will enlarge the bore diameter sufficiently that the stock-size cup seals won't hold pressure and their lip will roll over.

:beer
 
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LUCKY13

Guest
I found the problem. I removed the newly rebuilt/resleeved master cylinder. When I removed the piston assembly, I discovered that the very front rubber cup had a small cut in it (maybe from a burr left in the newly installed sleeve). I went to NAPA and bought a new rubber cup to replace the damaged one. I bench bled the master cylinder and installed it back in the car. I'll bleed the calipers tomorrow.
 
L

LUCKY13

Guest
I bled the system today and the brakes feel good, solid pedal and not near as much travel as before.
 

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