I know this is discussed a lot, but I'm still having trouble, and I want to clarify some things. I installed 4 new calipers and front hoses a few weeks ago. I tried to bleed it then, but didn't get much air out, and the pedal went to the floor.

The weather has been bad, so I haven't tried again until today. This time, air wouldn't stop coming out. My method is to put one end of a plastic hose into a bottle of brake fluid, and the other onto the bleeder. I then open up the bleeder, pump the pedal a few times to get the air out, and then bring the bottle down to the ground. Every time I did this, I'd get a bunch of bubbles after about 30 seconds. I then had to pump the pedal again because there was too much air in the hose to allow the fluid to move on its own anymore. After all of that, I think my pedal is worse than the first time I bled it.

I never got any air out by leaving the bottle above the caliper. Maybe I'm just too impatient though. Is this the correct method? I used the bleeding order that most people seem to recommend (LR I/O, RR I/O, LF, RF).

How would I know if a caliper is bad? Is it normal for this to take 5 hours and a liter of fluid, and still not be right? Could I have damaged my master cylinder somehow?

 

aharte,

Sounds like your opening up the valve and pumping the brake up and down with the bleeder valve open all the time. Did I get this right? This is a two person job, with the bleeder valve open only on the brake petal downstroke. The valve must be closed before the brake petal is released for the upstroke, or you just suck air back into the lines.

 

Yeah, you have it right. I thought that it could be done that way by one person as long as the other end of the hose stayed submerged. Maybe not.

 

Try raising the bottle higher than the caliper.

 

you can bleed the brakes with bottle and one person. make sure the hose is submerged in the fluid and take your time allowing bubbles to float to top before you release the brake pedal. also make sure the hose is tight on the bleeder it can suck air that way. have you tryed to gravity bleed it. take the cap off of master cly. and open one bleeder at a time leave open until fluid runs out of bleeder with no bubbles. do not pump brakes while gravity bleeding. give it a try either way it has worked for me dozens of times. also do not let master cly. get low make sure it does not get low enough to bring air back in system.

 

If I just open the bleader and let it go, the fluid stops flowing after a few inches. There is not enough pressure to force the air out of the hose, which is why I was pumping the pedal to get things going. Or are you saying that gravity bleeding is done with a hose that is not submerged?

 

yes. to gravity bleed you dont even need hose attached to bleeder screw. also leave the top off of master cly. but do not pump brakes with top off fluid will go everywhere.

 

You may want to spend the 69$ for the bleeder from MidAmerica or Ecklers...bleeding the brakes took me about 30 minutes...

I was too cheap to spend the money for this 'power bleeder'

get a garden sprayer at lowe's for $8 and some clear plastic hose... then modify an old master cylinder lid (hose nipples with NPT thread) and build your own 'power bleeder' for about $10... works absolutely great, is very easy...

 

I don't even mind bleeding brakes since I made mine. I took mine over to my buddys a few days ago and we bled the brakes on his car in about 15 minutes. And he had just installed new lines and brakes.
It works so well that last time I was bleeding the brakes on my Vette I went ahead and bled until the fluid was completely clean....

 

got any pictures? what/how did you pressurize the vessel? what size sprayer did you get for $8 ...did the sprayer contain fuild or just act as a pressure vesell? i like this idea...tell me more, thks bob how about we start a thread " interesting homemade tools"?

 

to the top for pics or more detailed info I need to do this tonight.

 

The only true way to get all the air out of the corvette breaking system is to use a power brake bleeder. I purchased one a few years ago and have since used it on serveral cars including my vette. It works fantastic.

If you take the car to Midas, or any other brake repair place, this it what they use. They can be purchased anywhere from 30 - 100 dollars. I purchased a basic one for 35.00 You dont need to over pay for one.

 

For these pressurized brake bleeding tools, does it matter whether it's adding positive pressure to MC or negative pressure at the bleeder? I found something that does the latter at the local parts store.

 

One problem that I and others on this forum have had with vacuum bleeding is that you'll often suck air past the threads of the bleeder making it difficult to tell when you're done. Some bleeders I could get it to work fine, others I'd suck bubbles out all day. I think power bleeding is probably more idiot proof as it's just kind of a pseudo pedal push.

I've had decent luck with gravity bleeding. But sometimes it seems like you can have too much air for the dribbling to start. Maybe gravity bleeding needs a sort of siphon effect to set up. In that case, just crack the bleeder, pump the pedal until you're squirting, then let it sit for a half hour or so.

 

I'm putting some pics in my gallery, will take a few hours for the 'approval'...

I filled the sprayer with 2 qt fluid and pressurized the system through the master cylinder, then opened one bleeder after another (started in the rear pass side of course),,,, whoops, done...
I would not use this pressure bleeding method with regular brake fluid, use only silicone fluid which is not corrosive !!!

 

I think your method is not correct because it sounds like air is being sucked back into the caliper because you are pumping when the bleeder is open. I used to single handedly bleed mine. I would use a stick like an old broom handle to push the brake pedal (so I wouldn't have to get in and out). You can also use an assistant if a broom handle isn't around. Here are my steps...

1. Close bleed screw.
2. Pump pedal up until firm. Hold foot firmly on the brake pedal (assistant) or prop with broom stick stuck on the seatback pressing firmly on the pedal.
3. Crack open the bleed screw. Fluid with bubbles will flow out and the pedal will fall to the floor. Keep the pedal on the floor until step 4.
4. Close the bleed screw before the pedal is released.
5. Repeat these steps for each caliper until the fluid that comes out when you crack the bleed screw contains no bubbles.

The above steps are free, but take time. If money is available, use the bleed screws with check valves in them. I can single-handedly bleed my brakes with them in about 1 minute per caliper.

Good luck -

 

thks i'll look for the photos later

 

REDBAD79

Saw the pics looks good guess I better get to work on that.

 

I tried just about everything even build the homemade bleeder. The old MC cap will not work unless uou JB weld it. Mine just pumped about a pint of Brake fluid on my garage floor. Your technique is correct with the bottle...tube...submerged in brake fluid. That is what I did to get the air out..however DO NOT PUMP WITH THE BLEEDER OPEN. Try this and you should be fine and wont make a mess of your car and garage floor.

1. Pump the pedal 5 times with the MC cap off.
2. Fill bottle half was with fluid and submerge 1/4od/.17id tube
3. open Left rear inner bleeder with bottle above the caliper
4. once flowing move bottle to ground.
5. tap caliper with hammer as fluid is flowing. (This is important...I was getting no air til I started this...then it released a surprizing amount)
6. let flow til bottle is full..keep MC full.
7. close bleeder and follow this order....LR/inner, LR/outter, RR/inner, RR/outer, LF, RF.

Tap every caliper with a metal hammer....check every hose connection to insure everything is tight...then do this process again. You should be fine...No mess...no power bleeders...no use of 2 gallons of brake fluid.

 

We have found that you need to power bleed and footbleed especially if you get an airlock. Takes 2 people. Make sure to use little psi if you are using dot 5