My 1980 Corvette was pulling to the right when I pressed the pedal to stop. Upon inspection I found a newer caliper on the right, the original was still on the left. Someone had changed the right one awhile back without changing both. I figured I would change them both out with new hoses and pads. Getting the parts was an ordeal in itself. Autozone couldn't get the left one at all after sending me the right one. O'Reillys sent me two that were mis-matched with seals falling out. Bought 2 Centric ones on Rockauto, one came with bolts loose, the left one I couldn't get to bleed, I think there was an obstruction in it. Got the replacement today, got it bled, both left and right are bled with a stream of brke fluid coming out. Now the pedal goes darn near to the floor. It didn't do this before so I'm scratching my head. I've changed brakes my whole life and never had this happen. Anybody have any suggestions? 

Hi, "I" Have found on my 75' that you can't pump them. Just one push down. Open, close bleeder. One push down. Open, close bleeder. Repeate. Seemed to work for me. Pumping them only seemed to pull more air into the system. I even had a brake place try bleeding them to no avail. Just cost me money for no success. 

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I'm with Mark on the not "pumping" method....but I have a pressure bleeder, so I don't have to deal with that anymore.

Years ago, I worked with a feller that was pretty sharp, and his method of bleeding(when replacing calipers/cylinders, masters) was to open the bleeder, and the pump the pedal(with the bleeder open) until solid fluid came out. THEN, he would start the pedal down, open bleeder, close bleeder, pedal up, then down, repeat as needed. It seems a little funky, but I've seen it reduce bleed time dramatically in some cases. 

I wouldn't even attempt it anymore without a pressure bleeder.....best $300 I ever spent...30 years ago. 

Joel Adams
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Hopefully this works - here's a link to a thread that shows the bleeder I made.  Scroll up and down through the thread for pics and chat about it. 

I'm guessing that the cost of the parts and pieces have gone up since I made it but I still have it and it works great.

Jim Olson 

"The Toys"...!!!  Save the Wave!

Where I've been in a Corvette...!!!

I use this.  Brake fluid is cheap.  Buy lots.

https://www.amazon.com/Motive-Products-250-System-Bleeder/dp/B00CJ5E1GS?ref_=ast_sto_dp

My wife and I sure appreciate the suggestions, she works from home (thankfully) and has to keep coming out to help me! So we thank everybody for the help. I never knew it was so tough to bleed Corvette brakes but it is apparently a thing. I kind of remember rebuilding the calipers on a '71 I had back around 1980. I must have gotten lucky then because I don't recall any problems. I wonder about the rebuild quality on the calipers I have now, the little "O" rings inside and the two halves bolted together and maybe not lined up, they seem a bit off. Do the rebuilders bench test them? There are no leaks but could they be sucking air? What a terrible design. Sorry wife but I'm going to to try the one push method, if that doesn't work then the pumping with the bleeder open method, lastly I will try a bleeder kit. All great ideas! I will post an update.

By myself today so no help pushing the brake pedal. Bought a Mightyvac bleeder and was able to get a good flow out of the left caliper. The right caliper I must've pumped the thing 50 times and still getting air with a sputtering of fluid. I haven't even had to put fluid in the master cylinder. Still no pedal. Alternately tried slowly pushing the pedal down and holding with a board, didn't work. As I push the pedal shouldn't there be a gurgling of the brake fluid in the master? It does nothing as I work the pedal. Is it possible the master cylinder is bad? Clogged? What about the proportioning valve, a video on Google says it could be tripped or something if brakes won't bleed. I'm about to buy the Motive pressure bleeder like F4Gary suggested and give it a try but I may have other problems. I just don't understand how the right caliper and line could have so much air, unless it is a bad rebuild and is sucking air somewhere. The brakes were decent before but the car pulled to the right when putting on the brakes so I assume the master is or was okay. 

My experience with the Mighty Vac is it can pull air in from the bleeder threads.

I would suggest bleeding the whole system.  There might be some residual air somewhere in the system.  The sequence that always worked the best for me was

1. right rear outside 
2. right rear inside 
3. left rear outside 
4. left rear inside 
5. right front outside
6. right front inside
7. left front outside
8. left front inside

Jim Olson 

"The Toys"...!!!  Save the Wave!

Where I've been in a Corvette...!!!

Hi, Unless the 80s are different, my 72, and 75 only have one bleeder on the fronts. No inside, outside! 

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I pulled the trigger on the Motive Bleeder Set. Like Norsky suggested I will put the car on jackstands and bleed the whole system. This car has one bleeder on the front calipers. I think the Mightyvac could have been pulling air around the threads like F4Gary said, makes sense. I was wondering how the Motive system could be better but I see how it pushes the fluid instead of pulling on the system like the bleeder screw types. Another question. The master had some fine rust in it, I sucked out all of the fluid and put new in. Is it possible some rust is clogging something? Would it be harmful to remove all fluid, take apart the lines on the front where they meet the hoses, and blow air in the front resevoir holes on the master?

You have to re bleed the entire brake system. Start with the passenger side rear, (it’s the longest line) then driver’s side rear. Then passenger front and finally driver’s side front. If this doesn’t fix the problem, you have a leak somewhere in the system usually a worn out brake line. The short rubber ones fail before the metal ones in most cases. They are easy to replace, metal lines, not so much. Hope this helps.

When you use your Motive, don't try to use the chain clamp system they have.  Use a piece of angle iron/aluminum and a big C-clamp to clamp the Motive top to the master cylinder.  When you are done, put the Motive  on the floor and relieve the pressure in the tank by unscrewing the top so the fluid in the hose can flow back to the tank as you unclamp it.

Some folks don't put fluid in the tank and just use it as a positive pressure source on the master.  I tried that and blew all the fluid out through the caliper and had to start all over.

Brake fluid is cheap so buy more than you think you need.

I have one of those critters! Cannot get a good seal from the top to the mastercylnder. Pressure will not build to force fluid or air out. Brand new! Using pedal is better. 

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I finally ended my brake bleeding nightmare by gravity bleeding them.  It was the only way I found that let fluid run through REMOVE air without pushing air bubbles back and forth. Before I figured this out I swear I was buying DOT 3 by gallon, pumping the pedal endlessly and never seeing a clear stream from the bleeders. 

I read lots of threads about the wonders of the Motive tool… but I also read a lot of threads from guys that couldn’t get a seal at the master. Didn’t want to spend more money on a tool that may or may not work for me. Just my $.02. 

steve

Sounds good but on one side I get nothing coming out, even with the hose disconnected from the steel line. I'm thinking the system, the master, and proprtion valve are vapor locked or something. 

Ok up on jack stands all around. Trying gravity bleeding. I have fluid coming out of all bleeder screws! How much should I let come out to ensure the air is out?

For me, it was until fluid came out w no air bubbles. It’s rather slow, fluid just dribbles out rather than getting pushed out in a jet. 

I used a long clear tube off the bleeder screws so I could watch the bubbles moving.

Just make sure reservoir doesn’t run dry.  

Probably because they tried to use the supplied chains and wing nuts instead of a C clamp to secure the top to the master.

I've not had a problem with it not sealing.

Good to know. If (when) I have to crack open the brake system again, I will give the Motive bleeder a try.

I recall at the time I was just feeling rather raw from spending so much on replacement calipers (my second set) and many, many quarts of DOT3 🙂. Another tool seemed like a bridge too far. 

Sometimes you just have to pay the guy.  I needed a rear decklid spring compressor to change out my springs.  I tried all the homemade suggestions and couldn't get the old ones out.  A former sponsor on here had a "home made" tool that would work.  It's 2 big washers welded to 2 pieces of  bar stock.  Looked home made but it worked.

It cost me $51 dollars for a "tool" I will never use again.

Years ago I had a heck of a time getting getting a good pedal when I replaced all the calipers on "The Toy" (my homemade pressure bleeder sure got a workout on that project!).  Thankfully the local Corvette parts outfit I bought them from was good about swapping out (multiple times) what I thought were bad calipers.  Turned out it was the new master cylinder I had bought from them that was the culprit.  Swapped it out and didn't have any more issues with the brakes. 

"Mr. Apple" has pointed out many times that a new part doesn't necessarily mean it's good.

Jim Olson 

"The Toys"...!!!  Save the Wave!

Where I've been in a Corvette...!!!

UPDATE. Gravity bled all four corners. The fronts had a steady flow of drips, the rears started out dripping pretty good but then they just stopped. Haven't got the Motive yet so I used the Mightyvac on the rears, worked like a champ. I could see several bubbles coming out until it turned to all fluid. Not sure how the air got in the rears since I only changed the front calipers. Probably from pumping the pedal and it went through the propotioning valve to the back? Not sure how that all works. I now have a good firm pedal! Hallelujah! Probably return the Motive (or put it on ebay) because I don't think I will ever use it. Thanks for all the help guys!

Is the car stops in a straight line now?

I haven't put the wheels back on yet. May have spoken too soon. lol.

Car back together and on the road again. Brakes work perfectly. Thanks to everyone for their help!