So I had some brake trouble (busted line), but I fixed it. I have confirmed that the new line has no leaks. But I can't seem to get the brakes bled! It is driving me crazy.
I got a hand pump, and it always makes bubbles. Always. If I try the gravity approach, it seems I have no air in the lines at all. The pedal is still soft, and does very very little to stop the car. I have bled three of the large bottles of fluid through it, and still no luck. The master cylinder is one year old.
Help?

 

Have you followed the proper sequence? LR inside,LR outside-RR inside,RR outside-LF-RF. Don't get freaked out by the air bubbles with a vacuum pump bleeder. Those are just coming from around the bleeder valve. They really do work. Also, as you were bleeding I hope you didn't let the resevior run down and suck air. Otherwise you now have more air to bleed out. Good luck.

 

You need to get two people and do the old fashion bleeding. I have electric vacumm pump and I still have to pedal bleed with two people. You could of lost the master cylinder or the proportionate valve when you broke the brake line. A drop in sudden drop in fluid causing a big stroke could destroy either of them. Good Luck

 

Jim

I know they'll be replies to the contrary, but I don't think you can beat the two operator method. With a helper pushing the pedal on your command you release and tighten the bleed screws. My wife and I do our 78 each year, it take less than an hour now to do the whole car. Fill the reservoir, attached pipe to bleed screw and be ready with spanner (wrench). Give the "down" command, release screw. When the helper (slowly) pushes the pedal to the bottom of its travel, he or she says "down", you tighten the screw and tell him to release the pedal. Repeat as necessary. Top up the cylinder and move to the next wheel/screw. Remember there are two screws on each rear calliper. I also follow a slightly different order than Magnum 81 as I start at the screw furthest from the master cylinder, hence right rear, outer then R/R inner, L/R outer, L/R inner, R/F, L/F.

Good luck

 

I aggree that nothing beats the 2 person method at all. I have just one other comment to make on that. I have found that by just pumping the pedal up and holding it down while you release the bleader valve not only can be messy but each time you close the valve you stand a chance of sucking in a small amount of air as well. The method that I have used is basically fool proof. Take a water bottle, the kind that they sell the bottled water in, and fill that about a quarter of the way with break fluid. Get a small vacuum hose and put that on the bleeder valve incerting the open end into the bottle of fluid. When you open the bleeder you will see the air bubbles in the bottle, and when you close the valve should anything be sucked back in it will be fluid not air. Do each caliper as stated in the order of bleeding posted above. When you see no more bubbles in the bottle you should have a stiff pedal. Most improtant make sure that you don't run the master dry or you will have to start all over again. After each caliper open the master and back fill what ever you need replacing the rubber plunger each time. Also if the old fluid comes out brown and nasty looking do no reuse it in the master replace with fresh fluid.
Works every time for me,
Hope that helps,
JoeB

 

I had big problems with this last year, runout forced me to bleed every week. Must have used a gallons of brake fluid before I found out how to do it....

BTW: Anyone who knows why they had to use two bleeders on the rear calipers?

I first tried the "standard" version with another person pump the pedal and me opening and closing the valve.
It sucked large amount of air!
(Has worked on all other cars I've owned, something must be "abnormal" with the caliper piston seal design on the vette...)

My conclusion was that the vacuum created in the system when the pedal is released sucks air. If you release the pedal very slowly less air is entering the system.

This is what I recommend, and you can do it without help.
Step one:
First hook up a bottle to the inside bleeder valve like JoeB described.
Then pump the pedal, push hard, but release slowly. Let the bleeder valve stay open all the time. You can watch the master cylinder fluid level while pumping.
When no significant bubbles are visible you close the valve and move to the outside caliper valve (rear only), repeating the process. (use transparent plastic hose to the bottle)
Step two:
Gravity bleed both caliper sections for a while, closely inspecting the hose for tiny bubbles.
Finished!

You might have to do a gravity bleed after a few miles of drive as there will probably be microscopic bubbles trapped after the system has been fully drained. They merge together to a larger bubble at the valve position (top of caliper)

Last wither I got rid of the runout.
Thought I would also have to install o-ring pistons, but no, haven't had to bleed once this season and pedal is still firm..:-)

 

The hand vacuum pumps will pull a small amount of air in to the line from around the threads of the bleeder screws. Since they are being pulled in to the vacuum system and not in to the brake system, they will not cause a problem.

That is according to my vacuum bleeder system instruction manual.

 

Oh no! Now youre working on you own car???? Don't let her get mad at you Jim. Her dash lights will been flashing, the horn honking, shooting lug nuts off the car! :lol: :D :lol:

So how have you been! Have you been hitting the cruises up at Chesterbrook???

Best of lucks with the brakes bud! There's lots of good tips here!

 

Yes the tips are great! Right now I am so frustrated and when I get frustrated I take everything apart... and end up with lots of new parts. One broken brake line has ended up with new calipers and shoks... may be time for an idler arm and clearcoating the wheels too!
Mike- I am trying very hard to work on my own car. Baby steps. Two years ago I had never changed a tire. Now calipers and shocks are a big deal but I think I can handle it, I think. I completely redid the VW bug brakes. Made a lot of mistakes the first time, but got the bleeding thing down. Now I have to figure out what is wrong with my chevy approach. The new plan is to wait a day, and start all over again slowly and less frustrated. And with a couple of gallons of fluid!
Wish me luck!
Thanks again!
Jim

 

start at the rear, put some vacuum hose on the the bleeder,the other end in a clean container(pop can).Pour some new brake fuel in the bottom of the can. With fluid in the can, and the hose in the fluid,and the other end of the hose on the bleader, open the bleader and punp the brakes (5-6) times. Close the bleader. Repeat at all wheels. Repeat if nes.
This is the best way to bleed brakes, and only takes one person.

 

I've got to agree with JoeB (woodworker), he and I have done both his brakes and mine, and once you can see no more air in the water bottle you know when all the air is out of the system. It normally takes about an hour to bleed off my 78. Keep the master fluid full, or start over. good luck

 

If the MC went dry, you must bleed that first before the calipers.

 

Just to add a little to these great tips, I use a electric vacumn pump(normally used in A/C work) and hook up to the bleeder screws with a tight fitting clear vacumn line, turn on the pump, and it is done! Real fast and easy. Don't suck the brake fluid into the pump though. ;)

 

Okay, I am almost done. I think. The day off to settle down is helping. The pedal isn't stiff, but much better. I am going to buy a clear plastic tube that has a lip on it, and gravity bleed while I finally clean up. This should do it. One of my big frustrations was that $30 will buy a fancy little pump with all kinds of plastic adapters, but none of them will hold on to a bleeder screw :rolleyes: . Lessons learned:
Never bleed brakes angry.
Never forget that you have an open bottle of fluid in your hand (poured the WHOLE thing all over the fender!).
Always have an extra brake line on hand when replacing a caliper.
The only thing worse than replacing one shock? Replacing three!
The gallon size of brake fluid is worth the extra few bucks.
Driving a volvo sucks.
Thanks again,
Jim