HELP - No Brakes!!!

der Mond · 09-24-2006, 11:11 PM

I’ve had the car on blocks 8 weeks with the brake pedal partially held down to keep from draining the fluid. I installed new rubber brake lines and short hard lines to the calipers, new calipers, new rotors, pads and emergency brake shoes. I let the brake pedal go, siphoned the old brake fluid from the reservoir, wiped it out with a lint-free cloth, filled it with gold DOT 4 fluid and used a Motive Power Bleeder at 12 lbs pressure, air-only. I went around right rear, left rear, right front, left front altogether twice tapping the calipers with a rubber hammer. Made sure there was ample fluid in the reservoir. Seemed like the air bubbles had stopped and the color had gone from ATE blue to gold. I tried to bleed the clutch slave cylinder and found it needed a smaller wrench (7mm apparently) so let it go for now. I have no resistance on the brake pedal, but have not pushed it past half-way down. I’ve pumped it a bunch of times to no avail. No brakes. Any ideas would be immensely appreciated.

Jim Smolka · 09-25-2006, 02:04 AM

Are the bleed valves on the top of the calipers? If they are on the bottom, then the calipers are on the wrong side. Don't ask how I learned this many moons ago

der Mond · 09-25-2006, 08:00 AM

I should have mentioned that the bleeders are all up in the proper position, and that I intend to flush the gold fluid with more Ate Blue but the no pedal now worries me. Ate Blue is expensive, especially FedEx'd to Alaska.

Porsche_911s · Porsche_911s's Garage

'78 SC - standard brakes

I am having the same problem after rebuilding the my front calipers & changing the master cylinder with a new one. The front have a very strong stream of fluid coming out with air at first. Now they seem to just shoot fluid. The rear only dribbles out a little fluid and it sounds to me like there is a"swoosh" at the "t" connection in the back. I bought a power bleeder and plan on putting it up on jacks and removing the tires to get a better angle.

Superman · 10-06-2006, 11:51 AM

Relax, both of you. Sometimes brakes just need a bit more attention. if I had NO pedal at all, I would start at the MC. I would, frankly, do it the conventional way. Get an assistant and instructed them properly (don't push the pedal ALL the way down, etc.) and coordinate an in-situ MC bleed. If necessary, raise the front and/or back of the car so the MC has been bled at all angles. With the pedal being pushed. Then re-bleed the lines. Eventually, unless there is an open line somewhere and you are spraying brake fluid all over the ground, you WILL get pedal. It just takes time and sometimes more than one iteration.

Zeke · 10-06-2006, 12:35 PM

Might be the simplest thing of all. Your pads are not against the rotors and it will take some pressure to get all 8 down to where they need to be. I'd hate to see you push the pedal to the floor because we all know that when you go beyond the "normal" travel range, you might get into an area inside the M/C that is not smooth and can damage the M/C seal. I feel the M/C needs to be removed and at least cleaned up with a brake hone when all the other work is done. Then, you could push down all the way as much as you like. This is what it may take to set the pads. Refill the reservoir when you get them set before taking the car out to seat the pads to the rotors.

Porsche_911s · Porsche_911s's Garage

Per Superman... I am getting a 6 pack to do this job right. Three for me three for my friend who will be instructed to not go to the floor with the pedal. That should get us good and relaxed.

But really, I read all the tech articles, Waynes book, and the Bentley manual. I like Wayne's comment that it takes some magic. hahah. I will give a try again. I just figured the power bleeder might help is there was air trapped in the new MC.

Porsche_911s · Porsche_911s's Garage

The Mity-Vac as shown in Wayne's book did the trick. I have brakes but the pedal still seems to travel too far. I took Milt's suggestion and looked at the front pads. Sure enough, I have lots of space between the front pads on both sides of the car. The MC seems to be firm and does not leak down once the pads make contact it just takes a little more travel than before.

Should bleeding them get them closer? Am I over-looking something obvious? Should I just watch the Red River Shoot-out and be done with it?

shbop · 10-07-2006, 07:41 AM

I used a Mighty vac to try and flush the system on my car. I must have pulled a gallon of fluid through the system. Never did get any brake pedal, until a friend came over, and we did it the old fashioned way. After two pumps at each corner, the brakes were terrific.

Jim Sims · 10-07-2006, 08:05 AM

I've used my Motive pressure bleeder for 8 brake bleeding episodes on various 911's; the jobs have included replacing brake lines, MC's, master cylinder input line grommets, bleeder valves, pads, etc. It's a one man, rapid, simple, no mess operation resulting in firm brakes obtained by just following the instructions on the bleeder to the letter.

Porsche_911s · Porsche_911s's Garage

Are the speed bleeders a worthy purchase? My rear speeders are rounded off and need replaced anyway, I figured when I rebuild the calipers I should replace the bleeders.

The vac unit did get me to this point, it was the only thing that the local parts stores had. I think I need to rebuild the back calipers and do it all over again. hehehe fun fun!

Thanks,

Jim Smolka · 10-08-2006, 02:40 PM

I like the speed bleeders, but then a pressure system is used followed by the 'good buddy pump and bleed method'

der Mond · 10-09-2006, 11:50 AM

Since my last post, I discovered I did have a little pedal pressure, but it was just below halfway down. I had been afraid to go lower because of exposing the seals to rough terrain. I bled the brakes again and found that if pumped once, I had enough brakes to safely stop the car. I drove like that for a week and the pedal improved each day. It was primarily a problem of breaking in the new caliper seals. I then flushed out the NAPA DOT 4 with ATE Blue and flushed and bled the clutch slave. I have a high, hard pedal and no more worries. I should mention that I used a Motive Power Bleeder "dry" with air pressure to the top of the MC only. Works just fine. Thanks for all your responses. Hope someone else got some help also.

ianc · 10-09-2006, 01:58 PM

If your master cylinder is new, you needn't fear pressing the pedal to floor during the bleeding operation. It is only after the cylinder has been in use for quite some time that gunk gets pushed forward into the bore and you may potentially damage the seals...

ianc

Porsche_911s · Porsche_911s's Garage

I just wanted to close out my part of this thread. I rebuilt the rear calipers and put in new speed bleeders on the rear. 5 pumps on each rear wheel and the petal was solid.

LakeCleElum · 10-28-2006, 02:47 PM

When you get real frustrated, bleed the master cylinder 1st before bleeding the calphers. Do this by backing off the flare fitting for each of the hard steel lines coming "OUT" of the master cylinder. When you release the flare fitting, have your assistant pump the pedal the same as you would as in bleeding the calipers.

Sometimes, you have so much air in the system, it takes this technique to get the fluid moving...