Brake bleeding- some progress
Thread Starter
Pro
Joined: Mar 2001
Posts: 633
Likes: 1
From: Hamilton, ON, Canada
Brake bleeding- some progress
A couple of weeks ago there were a couple of threads about difficulty in getting a hard pedal after bleeding. I couldn't get a hard pedal after using the pedal method and the vacuum method. Just had the car out for a test after doing a gravity bleed. Some improvement- the wheels will now lock up although the pedal still feels a bit soft. Don't know if gravity bleeding is the reason or if it's just because it was bled again. Anyway, the car is O.K. to drive and that's the main thing.
The gravity bleed was surprisingly simple and quick- flow was good indicating clear lines and took about 45 min/wheel to collect 1 liter total fluid.
The gravity bleed was surprisingly simple and quick- flow was good indicating clear lines and took about 45 min/wheel to collect 1 liter total fluid.
Race Director
Joined: Oct 2000
Posts: 11,891
Likes: 3
From: Kansas City, MO ...I'd like to go fishing and catch a fishstick. That'd be convenient. - Mitch Hedberg
How exactly do you gravity bleed the brakes? I've heard it mentioned here before, but never knew how to do it.
Thread Starter
Pro
Joined: Mar 2001
Posts: 633
Likes: 1
From: Hamilton, ON, Canada
You just connect clear tubing to the bleeder screws and run to a container to collect drained fluid. Take master cyliner cover off to allow draining. Open bleeder screws and fluid should drip out. Keep an eye on master cylinder level to prevent from running dry. You can bleed all four wheels at the same time if you have enough tubing & containers or do one at a time.
Some people believe this method is superior to other types of bleeding and at this point I'm not going to argue with them since it's helped me in a very frustrating exercise.
Some people believe this method is superior to other types of bleeding and at this point I'm not going to argue with them since it's helped me in a very frustrating exercise.
Le Mans Master
Joined: Oct 2002
Posts: 5,714
Likes: 6
From: Silver City NM
St. Jude Donor '05-'07
I just replaced my two front calipers. Tried gravity bleed first. Useless. Doesn't get all the air out. Vacuum pumps work nice for enlarging certain anatomical parts on males, but don't actually simulate the real world PRESSURE of a normal brake system. So I ended up investing in one of these:
http://www.motiveproducts.com/
Not only did it bleed the system, but it found a leaky caliper piston that would NOT show up with a gravity bleed or vacuum bleeder.
Also make sure you elevate the rear of the car HIGHER than the front to get all the air out of the rear calipers. Axle stands or ramps work fine for that.
Dep
http://www.motiveproducts.com/
Not only did it bleed the system, but it found a leaky caliper piston that would NOT show up with a gravity bleed or vacuum bleeder.
Also make sure you elevate the rear of the car HIGHER than the front to get all the air out of the rear calipers. Axle stands or ramps work fine for that.
Dep
Racer
Joined: Dec 2003
Posts: 411
Likes: 0
From: Arvada CO
Did the exact same thing.. This little piece of plastic was worth every penny!! The only issue I had was getting the darn nuts tight enough over the master cylinder.. I had a serious overflow... Makes for a nice stain on the garage floor.
Le Mans Master
Joined: Oct 2002
Posts: 5,714
Likes: 6
From: Silver City NM
St. Jude Donor '05-'07
Originally Posted by CruisinCO
Did the exact same thing.. This little piece of plastic was worth every penny!! The only issue I had was getting the darn nuts tight enough over the master cylinder.. I had a serious overflow... Makes for a nice stain on the garage floor.
Brake fluid had dripped on the exhaust pipes.
But that pressure bleeder was worth every penny I paid for it too.
Considering it can be used on a wide variety of cars, I think it's worth the price.
Dep
Racer
Joined: Dec 2003
Posts: 411
Likes: 0
From: Arvada CO
Hey Dep we have more in common that those darn nuts... We actually have the same birthday too. A few yrs apart, but same date none-the-less.
Happy belated!
FYI- I got smarter on the wing nut issue. I needed to use the power bleeder on my next door neighbors 72 Blazer last week so I went over to ace hardware and got hex nuts that I can torque the crap out of with my rachet..No leaks the 2nd time around after tossing the wing nuts.
Happy belated!
FYI- I got smarter on the wing nut issue. I needed to use the power bleeder on my next door neighbors 72 Blazer last week so I went over to ace hardware and got hex nuts that I can torque the crap out of with my rachet..No leaks the 2nd time around after tossing the wing nuts.
Melting Slicks
Joined: Nov 1999
Posts: 2,461
Likes: 354
From: Madison Alabama
I replaced the back calipers a few months ago and just did the front ones this weekend. I did a gravity bleed on both ends, worked out fine as I have a good firm pedel. I also tried the "speed bleeders" on the front, worked as advertised.
Readers Digest version of how I set up for the gravity bleeding...
1. Use clear hose that I picked up from the aquarium dept at Wally Word.
2. Used a tall, clear plastic food storage container that I picked up from the kitchen...hope she don't miss that one.
3. Filled the container with about three inches of new brake fluid.
4. Attached one end of the clear hose to the bleed screw, inserted the other end in the bottom of the container, ensuring it stays submerged.
5. Remove the Master Cylinder cover and top it off.
6. Open the bleed screw several turns and SLOWLY pressed the pedal down but released quickly. Keep an eye on the master cylinder to ensure it doesn't run dry.
Note, it will take a while to get things going, especially with new calipers. Literally had to pump between 75 and 125 times depending on the location of the caliper from the master cylinder...just when I thought I was doing something wrong the older, dark fluid began to show up. One note, don't be afraid to really open up the bleed screws.
Readers Digest version of how I set up for the gravity bleeding...
1. Use clear hose that I picked up from the aquarium dept at Wally Word.
2. Used a tall, clear plastic food storage container that I picked up from the kitchen...hope she don't miss that one.
3. Filled the container with about three inches of new brake fluid.
4. Attached one end of the clear hose to the bleed screw, inserted the other end in the bottom of the container, ensuring it stays submerged.
5. Remove the Master Cylinder cover and top it off.
6. Open the bleed screw several turns and SLOWLY pressed the pedal down but released quickly. Keep an eye on the master cylinder to ensure it doesn't run dry.
Note, it will take a while to get things going, especially with new calipers. Literally had to pump between 75 and 125 times depending on the location of the caliper from the master cylinder...just when I thought I was doing something wrong the older, dark fluid began to show up. One note, don't be afraid to really open up the bleed screws.
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Le Mans Master
Joined: Oct 2002
Posts: 5,714
Likes: 6
From: Silver City NM
St. Jude Donor '05-'07
Originally Posted by CruisinCO
Hey Dep we have more in common that those darn nuts... We actually have the same birthday too. A few yrs apart, but same date none-the-less.
Happy belated!
FYI- I got smarter on the wing nut issue. I needed to use the power bleeder on my next door neighbors 72 Blazer last week so I went over to ace hardware and got hex nuts that I can torque the crap out of with my rachet..No leaks the 2nd time around after tossing the wing nuts.
Happy belated!
FYI- I got smarter on the wing nut issue. I needed to use the power bleeder on my next door neighbors 72 Blazer last week so I went over to ace hardware and got hex nuts that I can torque the crap out of with my rachet..No leaks the 2nd time around after tossing the wing nuts.
It occurs to me that if I made a strip of 1/4 inch metal that ran along where the hold down bolts go, THEN used the nuts as you describe, the stress on the plastic top would be spread out along the length of the metal strips instead of being locted only at the nut locations.
Dep
P.S. Belated Happy Birthday!!!
Safety Car
Joined: Jun 2004
Posts: 4,372
Likes: 223
From: Beecher Illinois
New guy with my first post! I've used the power bleeder also. I found that the best way to mount the fitting to the master cylinder is to use 2 c-clamps, one over each compartment. I also do a pressure test BEFORE I put any brake fluid in the tank. Let it hold 20 lb. for about 10 minutes while I pull the wheels. Then I release the pres.at the tank and add the fluid. When finished bleeding, turn the tank so that no fluid is picked up by the hose and then open the front driver's side bleeder one more time while watching the air gap in the clear hose til it gets to the master cylinder. Bleed a touch more and stop. No mess.
Mike
Mike
