I can't seem to get a firm pedal on my '78 Camaro. I've tried bleeding the entire system multiple times and have replaced almost every brake part you can replace (all of them needed to be replaced anyway.) I tried those Russell "Speed Bleeder" screws to help me do it myself since I don't  have anyone to help me, but realized I was going around in circles when I discovered that several of them were defective and not preventing air from re-entering the system (those things are a POS.) I have tried gravity-bleeding, magnetic-bottle-hanging-above bleeding, and mighty-vac bleeding. I get a firm pedal when the engine is off, but 90% of it goes away when the car is started. My friend wondered if my rear shoes were adjusted properly, and one of them I know isn't, but still that shouldn't make such a big difference, should it? If anyone can suggest something for me to try I'd appreciate it.  

Have you replaced the brake booster? and does your car stop even though the pedal feels weak?

     The reason I ask if you changed the booster is that most of the older cars I have worked on, had two holes in the brake pedal arm, one for power brakes, the other for manual brakes, If you have it wrong,(if it has the two holes) then the pedal wouldn't feel as firm.

     The reason I ask how it stops, is that sometimes when renewing a brake system we simply forget how the pedal on a particular car feels. It might just be a live with it problem if you know what I mean.  

Yes, I have replaced the booster just the other week, but I've had the same symptoms with the old one - that is why I tried the new one. I do think I have enough firmness to barely hold the car still, but it is nowhere near enough to make it safe to drive. The whole reason I dove into almost a complete brake overhaul was because of a steady decline in firmness over a period of months. I wasted a bunch of time at one point trying to bleed the system before I discovered that the hard-line going to the back-left wheel was kinked and completely stopping flow to that cylinder. I figured I'd replace that line plus the front-to-rear and back-to-right lines, wheel cylinders and spring kit and I would be all set. But, I can't get a firm pedal. Like I said earlier, I know the shoe adjusters aren't adjusted, but that shouldn't make such a big difference. It is too rainy for me to work on it right now so I'll adjust those in a few days and see if that helps. Any other ideas? It is just hard for me to believe that there is still enough air in the lines to prevent a firm pedal after all of the careful bleeding I have done.  

The only other things I could think of would be a clogged up proportioning valve or a stuck brake caliper. but it isn't logical that all of them would stick open at the same time. But I have seen weirder things happen. I think I would probably haul the car to Meineke and let them sort out this troublesome setup.  

I have replaced the proportioning valve with a new stock one, so that isn't it. I think I had the calipers replaced several years ago, but don't remember. Besides, I can hear them working when I'm trying to bleed the system. Take it to Meineke? I guess I could, but the whole point in trying to do it myself is to save money - that is what car crafting is all about. I'd like to try to rope-in this problem myself as a learning experience. So far all I've learned is that my streak of having the most odd-ball problems with cars continues. Kind of ironic - I just finished re-doing the engine to make it really move, but now I can't get it to stop:-) I'm thinking maybe one of my fittings is sucking air, them being new and stainless steel, so I'm going to loosen and tighten the fittings going to the wheel cylinders a few more times in case the flare isn't mating well. I know none of the other ones are leaking because I've felt for fluid around them and they were all dry, right from the start. However, when bleeding the rear cylinders it is hard to tell because of all of the fluid which pours out from the bleeder screw. Thanks for your suggestions, though. I'll take more if you've got'em.  

I know the feeling of wanting to finish it yourself, however if it gets to be to much of a P.I.A, there is nothing wrong with chalking one up for a loss, another idea would be to go to your local auto parts store and ask the most knowlegable person there. My go to Advanced Auto guy has cured many a problem for me.  

I'm within a gnat's hair of taking it to the brake shop, but I want to exhaust all possibilities first. Today I fiddled with the rear shoe adjusters so that they slightly drag the drums. I loosened and re-tightened the two fittings going to the cylinders several times and re-bled the rear cylinders, the right rear first, then the left. I have a hunch that the shoe adjusters may be part or all of the problem. I'll know when I crank up the car as so far the pedal has been stiff until the engine is running. I'll try it out tomorrow because it is too late this evening (I have to take the battery out of my only running vehicle to start the camaro because the old battery died recently.) Does anyone know what the procedure is for using that little button on the left side of the combination valve to balance the front brakes? My brake manual just says "Ummm, duhhhh, ummm, don't forget to use the special tool to set your front brakes properly." VERY helpful. Oh, and I can forget asking my local parts store employees for help: The last time I went to get parts for a '68 Road Runner the girl there had never even heard of one, when I needed parts for my '73 F250 she asked "are you sure it's an F250?" as if she had only heard of F100's, and my friend went there one time out of curiousity to see what parts he could get for his '69 chevelle and she didn't even know what one of those was, either. There are other employees who work there, but I hate to pick their brain because it really isn't their job to diagnose car problems, just to supply parts for them. Diagnosing is for a mechanic, but I see your point. Well, gotta go for now. I'll post back with either victory or defeat so check back. 

Well, I adjusted the rear shoes and rebled those two lines like I said earlier and have only a small improvement. I'm wondering if the front calipers are stuck after all. I'll check it out, then set the car on fire.  

Yesterday I pried the brake pads away from the front discs just enough to see a crack of daylight in-between them, then applied the pedal and checked to see if the gap closed. Both front wheels closed, so that means the calipers aren't stuck, doesn't it? I also bled the front-right, then the front-left again, since I did the back-right and then back-left the other day. I now have enough pedal to feel safe on the road, but it is still nowhere near firm. Adjusting the rear shoes seemed to help, but only slightly. Could the old brake fluid have ruined the seals in the calipers and be causing the remaining pedal lowness?  

I'm no expert in this at all, but after reading the posts I can only stay with the basics. Hydraulic fluid does not compress, period. If you have a spongy brake peddle I can only think of a couple things, 1.) You're not getting the good bleed you think you are and there's still air in the lines(air will compress) or 2.) There's a leak somewhere, letting the pressure escape. I've never seen a soft peddle with a sticking caliper, even if the caliper is stuck applying the brakes, it should still be firm, as there is no air in the lines. I know this is going to sound like a pain in the *ss suggestion but find someone you trust and bleed it the old fasioned way with two people. Start at the passenger side rear, then move to the drivers side rear, then the passenger side front and then finally the drivers side front. You may have a bad bleeder valve and not know it because you're doing to much at one time. Hope you get it nailed down and fixed. Good luck and let us know how it goes.

I have enough brakes to get me around town now, but I would like it to be better. Maybe I need to bleed them a couple more times to get it firmer. Maybe I should just live with them the way they are. I am making progress. Bleeding brakes the old fashioned way with two people is nice, but I don't have anyone to help me. All of the bleeder valves are new, so that isn't part of the problem. I guess it has to be air still hiding somewhere, even though I have run several bottles of brake fluid through the system and tapped on  everything to free any stuck bubbles. Not once has the master cylinder come close to getting low enough to allow air into the lines - I'm very careful and take my time with everything. Anyway, although the problem isn't solved it is good enough for now so I'll let this thread die. Thanks to everyone who took a little time to comment.  

How can you say that you think you replaced the calipers? I can't believe any one would could say that. Either you did or not.I can remember most of my jobs. THe most that might happen is you forget to tighten something down. Ehh!

Lighten up, dude. I had some front brake work done several years ago, closing in on 5 or 6, at Pep Boys. At the time I told them to "just fix it" and I didn't pay much attention to what they did. Since I'm too lazy to find the invoice to see exactly what they did I said I don't remember if the calipers were replaced, which I don't. Anyway, I now have adequate brake firmness after several torturous brake bleeding sessions, adjusting the rear shoe adjusters, and replacing alot of old parts. Thanks to everyone who tried to help in some constructive way.