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After replacing front suspension requiring removal of front calipers I'm having issues with spongy brake pedal.
1) First attempt was using a Mighty Vac to use suction on front calipers to evacuate the lines. Result was spongy feel.
2) Second attempt was installation of Russel "Speed Bleeders" from Summit Racing. Depressed pedal appx. 10-12 times and collected appx 1/4 cup from each side... Still spongy feel??
The pedal is so soft with the engine running; (power brakes) I am concerned to back up the car and have it roll down my driveway uncontrollably!
A) Either I haven't pushed enough brake fluid through the lines?
B) When using Mighty Vac I may have sucked the reservoir empty allowing air in that is still stuck in the lines?
Or C) The "Speed Bleeders" are allowing air to pass across threads?
Any help would be appreciated. Small items like this get very frustrating!!!
And D. All of the above. Wonder why you have brake issues unless you did something to a brake hose while working on the suspension? IDK
The Speed Bleeders might have "tripped" the proportioning valve and will need to be reset. It detects a pressure loss and will offset. Bleeding brakes using the pedal, IS a pressure loss until the bleeder is closed. There is a tool to stop that. (See my profile photos)
Allowed air into the master? Yup, it happens. Sometimes those Vacs extract so fast you can't refill the MC fast enough. If that did happen, then a pressure bleeder may push the bubble thru or you will have to remove the MC and bench bleed. Two lines, two nuts. Not too bad a job.
Air leaking past the bleeder screw threads? Yes. Seems like those "over the counter" replacements are a little on the loose side in the caliper. A dab of anti-seize helps . . . somewhat.
Last edited by HeadsU.P.; Feb 14, 2018 at 07:02 PM.
First, what did you do to your brake system to have the need to bleed them?
I assume you are starting at the right rear caliper and working your way to the left front? RR -LR - RF - LF. I've never had any trouble bleeding my manual brakes using the gravity with an assistant method. I've done it 3 times since I've owned my car without any issues.
With all these "can't bleed my brakes" threads over the years I guess I should consider myself lucky or a brake bleeding Jedi.
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try a motive Pressure bleeder. You said roll down the driveway, Are you bleeding them on a level surface?
I tried the mughty vac and pumping and squirting. I had to do the whole system 3 times with the vac, then 4 more times with a helper pumping and me turning bleeders. That gave me an okay pedal. The pressure bleeder is fast and the best.
try a motive Pressure bleeder. You said roll down the driveway, Are you bleeding them on a level surface?
I tried the mughty vac and pumping and squirting. I had to do the whole system 3 times with the vac, then 4 more times with a helper pumping and me turning bleeders. That gave me an okay pedal. The pressure bleeder is fast and the best.
I agree. LOVE that thing. Read the threads on how to use it as it needs a little modification help right out of the box to use on our cars. Well worth the investment.
I use this for all my vehicles now. I just installed some air compressor quick disconnects on the hoses so I can keep the bottle pressured up. I never put fluid in the bottle, just use it for air pressure. With the C3 master, I recommend using a C clamp instead of the chains and hooks. Best tool I have found for bleeding.
Bleeding the brakes is a labor of love, that's for sure. As others have mentioned, gravity bleed is probably the most reliable way. I agree with Mr. Dmaxx3500 that some 'love taps' are helpful in dislodging bubbles from the sidewalls of the calipers.
If doing a bleed after breaking into the system, I normally START with 4 quarts of fluid. It sounds absurd, but this is not a "you get fluid and you're good" sort of deals. It takes a lot of time and attention.
I REALLY like Mr. Cagottzmann's contraption and this probably represents the best case scenario. Being able to "blast" some fluid through the system would peel the bubbles of the walls and really get the best result the quickest. Alas, I have not had the opportunity to build that contraption yet.
The only other method I've tried is by applying a vacuum at the calipers. That's been a good way to get the flow started (after replacing my master cylinder), but it has never given me "a good bleed". I always end up gravity bleeding to the finish line.
I used a Mityvac. Air was continually getting sucked in around the stock bleeders. Putting some grease or silicone grease around the base of the bleeders helped but I still wound up using a fair amount of brake fluid in the process.
Bought a Motive Brake bleeder and problem solved. their clamping system for the master cylinder cover sucked though. I used a big C-clamp and a wood block. Solved the problem. Do a search, there are tips on using the Motive on this Forum.
Use the Mityvac to check vacuum, etc, and get a Motive bleeder for your brakes. You'll be glad you did.
I tried peddle pusher, those special bleeders, and mighty vac, wound up gravity bleeding. No muss, mess or fuss, just patience. I'll never bleed them any other way.
I never could get a Mighty Vac to work right. Now I have a Motive power bleeder AND Speed Bleeders. I use a C clamp and a piece of angle iron on the master cylinder with the power bleeder. Works great.
I tried peddle pusher, those special bleeders, and mighty vac, wound up gravity bleeding. No muss, mess or fuss, just patience. I'll never bleed them any other way.
Last comment on this thread:
If you need a special bleeder or procedure, other than using gravity bleeding with a helper to step on the brake pedal, there is something wrong with the brake system. If any special tools like power bleeders, mighty Vac, etc are required in order to bleed the system outside of the gravity bleeding procedure, the system should be checked thoroughly for an issue. A properly sealed, operating C3 brake system with correct rotor runout does not require any special bleeding procedure other than gravity bleeding just like most cars today and back in the day.............
Last edited by jb78L-82; Feb 17, 2018 at 04:10 AM.
If you need a special bleeder or procedure, other than using gravity bleeding with a helper to step on the brake pedal, there is something wrong with the brake system. If any special tools like power bleeders, mighty Vac, etc are required in order to bleed the system outside of the gravity bleeding procedure, the system should be checked thoroughly for an issue. A properly sealed, operating C3 brake system with correct rotor runout does not require any special bleeding procedure other than gravity bleeding just like most cars today and back in the day.............
I agree
The time I changed the flexible line to caliper from rubber to braided steel I had a hell of a time getting the copper washer on the caliper to seal. Took most of the day to get them to not leak for some reason. That is the most problems I've ever had bleeding the my brakes.
Gravity bleeding is fine but it does not "flush" contaminates out such as moisture lying in a low spot of the brakelines nor does it remove trapped bubbles like pressure methods do.
Last edited by HeadsU.P.; Feb 18, 2018 at 07:36 PM.
Issues Bleeding Stock Brakes
