# minor brake issue likely just not bleed all the way down...



## virginiavenom (Feb 20, 2011)

ok. so with this great new brake system, I have gotten fluid to all calipers. no problem right. and before anyone asks, no the MC didn't go dry. not the first time I've bled brakes, however for some unknown reason, I had my helper doing some pedaing for me, had him hold down, tighten the bleeder, move to the next one, have him pump a few squirts out until I don't see any bubbles, have him hold, and tighten....same for the fronts.....still no hydraulic pressure back on the pedal, it is a vacuum booster pressure only, no hydraulic pressure. pedal goes to the floor with relative ease (car is off please note, which should not affect getting brake pressure. ) we tried this three times and still have no change in pedal pressure. we checked all fittings, no leaking anywhere, no kinks....looking for suggestions


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## Rukee (Feb 8, 2007)

What type of brakes on the rear? Shoes and drums? If so, are they adjusted properly?


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## geeteeohguy (Feb 2, 2008)

You say it's vacuum pressure only, no hydraulic pressure. How could that be? I'm confused. Did you bleed the master prior to installing it or prior to the bleeding of the rest of the system? You need to bleed the master, then fill it up, remove the cap, and gravity bleed the brakes, one corner at a time. I've always bled master cylinders with a syringe by squirting brake fluid into the outlet ports until the bubbles in the reservoir become a solid stream of fluid. Takes less than 2 minutes.


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## virginiavenom (Feb 20, 2011)

hmmm....well, I didn't think about bleeding this master cylinder as it just has hard lines where most MCs I've done I use the bleeders on the MC. it's disc rear as well as front. I filled the MC first with all lines attached and opened the Passenger Rear bleeder to allow it to push fluid into the long and worked my way around until I had fluid coming from each bleeder. took a while for the backs of course, but it got there. please explain your MC bleeding a little more. I always thought a MC would pull fluid down into itself any way. but I guess it makes sense that there could be air lodged in the MC


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## GTO JUDGE (May 14, 2005)

To add what geetee said, if you drain the MC while bleeding the brakes re-bleed the MC at the MC's bleeders, you're sucking air if the MC goes dry.


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## virginiavenom (Feb 20, 2011)

MC was never dry....I just never bled the MC....


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## Rukee (Feb 8, 2007)

Yeah, you should have pre bled it on the bench before installing on the car. They make a kit that uses clear plastic hoses you run from the outlet ports back to the bowl. Using a big screw driver or whatever, mount the MC in a vise and push in and release on the plunger only going about half way down and continue till you see no bubbles going either direction through the hoses. Then reinstall on the car and bleed it again using the gravity method.


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## virginiavenom (Feb 20, 2011)

rukee, explain the gravity method please, I was always told to pump to solid fluid, pump and hold while bleeder is being shut. I will bench bleed, but once I remove the tubes from the MC, won't it allow air back into the MC before I can get it connected back to the MC lines from the distribution block?


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## Rukee (Feb 8, 2007)

Nope, you'll be fine.
Gravity method is to leave the cap off the MS, starting at the furthest bleeder away, open and just let gravity push the fluid out. I would bleed the whole MS worth of fluid to be sure you have all the air out. When done, pump up the MC (if everything is new, it may take 10-20 pumps to collapse the calipers), and then gravity feed again just to be sure.


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## virginiavenom (Feb 20, 2011)

cool. I was also thinking about using a small bottle with brake fluid in it and putting a tube coming from a bleeder into the bottle as long as it stays submerged in the fluid it should allow me to one person bleed each brake after doing the gravity right? I'll take your word for the bench bleed. I'll let you guys know how it goes.


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## 69Goatee (Aug 14, 2009)

Did you check the pushrod length? The one between the booster and M/C. It may be too short, only pushing in on the MC at the end of the pedal stroke.


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## virginiavenom (Feb 20, 2011)

I'd like to think it was. since it came from the shop that designed the system for me....


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## geeteeohguy (Feb 2, 2008)

How I bleed master cylinders: remove both hard lines. Fill about half way with fluid. Fill syringe with brake fluid and gently inject it into to now exposed outlet ports. You will see a stream of air bubbles in the reservoir, followed by a solid geyser of brake fluid. When all air bubbles disappear, top off fluid and look at your outlet ports, which should now be dripping. This can be done "on car" if you use rags and are careful. Hook up hard lines and bleed the rest of the system. I've done this for 25-plus years and it always works, requires no messy pumping, and is fool proof. You MUST bleed the master before trying to bleed the rest of the brake system. Good luck.


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## Rukee (Feb 8, 2007)

I have a tool called the Phoenix Injector System that basicly does the same thing. Works great for some clutch system were the MC is angled hard with the firewall.


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## virginiavenom (Feb 20, 2011)

got it working. did the gravity feed, seemed to help a little, but still went almost all the way to the floor. these particular front calipers have a little allen head opposite of the bleeder valves I cracked them open and got a solid stream of fluid, went to back to the bleeder at the top of the caliper and cracked them, and bam, a BUNCH of air came out of both calipers. can't explain it. now the pedal moves about 1.5 inches and is very hard. pedal is very responsive. thanks for the help gentleman. now I move on to my power steering system, which is only in need of a hose, then installing my fuel tank, and then....the dreaded hurst shifter linkage on the transmission. yay.


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