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#2512194 - 06/23/18 12:53 PM Another brake bleeding dilemma!!!
Blucuda413 Offline
top fuel

Registered: 01/24/03
Posts: 2438
Loc: Alexandria, LA
Background: Basically changed entire car over last 2 years. New aftermarket 9" rear, built new k-member and added Lamb struts, added rack and pinion steering. Reason for drastic change was to support added power from roots blown smallblock. Car is 68 Barracuda Notchback.

Still using stock brake pedal assembly & rod. Only old tubing is from firewall back to proportioning valve in rear. Braided stainless line from valve to T on rear. New tubing from T to each caliper (Wilwood rear brakes).

In front everything new from MC to Lamb calipers. From rear MC port I have braided stainless to Roll Control and from the Roll Control to T. From T new hard line to each frame anchor point. Braided stainless from each anchor point to caliper.

I'm on my second MC with same results with each. I have bled these brakes at least 15 times using all methods I have access to. Vacuum, pump & hold, drip method and pushing fluid from caliper back to MC. The end result is the same. The first push on the pedal it goes to the floor. On second or third pump I get some acceptable pedal. After a few moments the pedal will again go to the floor but provide pedal after 2 or 3 pumps.

I've bled master cylinders alone more than once and I can separate systems to MC, front system and rear system and each individual system will hold solid vacuum.

I'm at a loss and any recommendations are appreciated. I have another new MC to try but I don't really think it is a MC problem, altho my son believes it is.

Thanks, Max

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#2512238 - 06/23/18 02:59 PM Re: Another brake bleeding dilemma!!! [Re: Blucuda413]
CMcAllister Offline
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Registered: 12/30/05
Posts: 2474
Loc: Fulton County, PA
What brakes were on it? What MC are you using? Sounds like MC bore is too small. 4 piston calipers with 1.75 bores on all 4 corners needs a big bore MC like the Strange 1.125".

Not a fan of those prop valves. Unnecessary if the system's correct, but that's another conversation. Just make sure it's wide open when bleeding.

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#2512241 - 06/23/18 03:07 PM Re: Another brake bleeding dilemma!!! [Re: Blucuda413]
therocks Offline
Its Lost

Registered: 01/20/03
Posts: 19339
Loc: Niles , Ohio
Are the bleeders for calipars pointing up?Thats the first thing to check.I had mine on upside down and had the same problem and Ive done brakes as a tech for decades.Its easy to do.Then if not that get some plugs and block off 1/2 of master and see what it does.I run 70 C body master one all disc we convert.Even if we run drums the same master just for drums.Rocky
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#2512352 - 06/23/18 09:07 PM Re: Another brake bleeding dilemma!!! [Re: Blucuda413]
Blucuda413 Offline
top fuel

Registered: 01/24/03
Posts: 2438
Loc: Alexandria, LA
Guys, thanks for replying! In previous configuration the car had the same Wilwoods on rear and stock front discs. MC bore was 1.062, and everything worked good. When going to 9" I had Dr Diff put Mopar ends on axle tubes so I could reuse the Wilwoods.

You may be right on MC size. I thought I did the math correctly to determine size and the first MC I tried was a 7/8 bore. The one I have on there now is a 15/16 bore. The new one I haven't tried is either a 1.062 or a 1.125. It's one from Ehrenburg.

Rocky All bleeders are pointing up except one. The Lamb calipers cannot be removed like the Wilwoods, the rotor must be unbolted from the wheel to get the caliper off, not an easy job. However if that is the problem I will figure a way. I have tested MC by blocking each port as you suggest and in both cases it held vacuum steady.

My next step will be to try the larger MC, will report the results.

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#2512409 - 06/23/18 10:27 PM Re: Another brake bleeding dilemma!!! [Re: Blucuda413]
biff426 Offline
super stock

Registered: 04/03/05
Posts: 730
Loc: Delaware
ALL the bleeders must be on top if not you will always have air trapped in that caliper

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#2516051 - 07/01/18 06:49 PM Re: Another brake bleeding dilemma!!! [Re: Blucuda413]
Blucuda413 Offline
top fuel

Registered: 01/24/03
Posts: 2438
Loc: Alexandria, LA
I now have pedal!! Tackling what I thought would be easiest I took the spindle mount wheel off the side where the bleeder pointed down. I had to completely disassemble the brake so that I could turn the piston side upside down so the bleeder pointed up. So I could better control the vacuum I used a large syringe to pull the air out of the line. After much playing with it I got all the air out and now do have a pedal. Will be glad when I get this thing cranked so I can check them out. Thanks for the inputs!!!!

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