Spongy Brakes after bleeding. "HELP" :(

[fsharp1]

Hello all,
Ima a newbie and appreciate any help
I have spongy brakes on a 1974 bronco, 302, auto trans, new cylinders on the front, these are stock brakes, these are not power brakes
Drums all around, I noticed the master cylinder is leaking from under the cap does this matter? ... more then happy

 

[shamu]

How tight are your drums on all 4 corners. Example can you hear the brake pad slightly making a noise as you turn the wheel? Or did you manuel bleed on the MC?

 

[Pa PITT]

....Here my RedNeck Way to bleed the Brakes... Fill the M/C leave the cap off .. Get a helper who doesn't require as much BEER as you do. ''Put him under the Bronco to watch for action''... Then Fill M/C and open valve 1 ... OPPSITE the M/C .. LET IT DRIP.. MOVE TO NO .2 .. let it drip .. close it off ..then to Pass side rear left, no 3 let it drip.. get another Beer ... Maybe get the 3rd beer if the tunes on the Radio were good. ... REMEMBER if you let the M/C RUN DRY THEN you have to start over on Beer. I mean you have to start over on Brake Fluid & Beer . Then when you get to the Right Rear and about the 4th Beer.. Keeping a close EYE on the M/C Not to let it go dry.. and there is a puddle everwhere .. You should have a BUZZ & Brakes.
.....................................
... What I mean is starting at the front draining all ... ALL .. the air out slowly. Watching for bubbles until it clean .. You can really empty a M/C faster than you'd expect .. But by the time you get to the back .. LAST wheel cyl.. It'll be bleed and you'll have Brakes.
.........
Some one else was having this trouble about a year ago .. They leed my way and enjoyed the BEER .. and had Brakes When Done.
.......
..............Happy buzz.......

 

[fsharp1]

Shamu: I used a mityvac to bleed the brakes, I'm really not sure how tight they are actually

Papitt: I like the way you think

 

[ttkelly]

I too am a newbie so take this with a grain of salt! That said, my two cents are below...
What does it sound like when you feel the spongie part of the brakes? It may be the same issue I had a few months back when bleeding (and allowing the piston to be depressed farther than ot had been in years) the brakes the piston in the plastic/rubber linner of the master cilinder was torn allowing the brake fluid to squab past. See the last photo of my thread below.

A word of advice. If you have the disc brake conversion make sure you don't pick up a stock master cylinder for the old drum brakes or you will need to remove the residual pressure valve. Good luck!

http://classicbroncos.com/forums/showthread.php?t=182833

 

[ttkelly]

I too am a newbie so take this with a grain of salt! That said, my two cents are below...
What does it sound like when you feel the spongie part of the brakes? It may be the same issue I had a few months back when bleeding (and allowing the piston to be depressed farther than ot had been in years) the brakes the piston in the plastic/rubber linner of the master cilinder was torn allowing the brake fluid to squab past. See the last photo of my thread below.

A word of advice. If you have the disc brake conversion make sure you don't pick up a stock master cylinder for the old drum brakes or you will need to remove the residual pressure valve. Good luck!

http://classicbroncos.com/forums/showthread.php?t=182833

Just re-read your post.. Drums all around :-[ thus dissregard my comment about which master cylinder to get! I was just in the zone reliving my horror! ;D

 

[DirtDonk]

Is the pedal actually spongy, or is it that it just travels farther than you think it should, but gets firm when the brakes are engaging?

If firm, but the travel is too long, then check your shoe adjustment at all four wheels, like shamu was talking about.

If it's actually spongy though, then it sure sounds like air is still in the system somewhere. Did you replace the master cylinder too? Or just the wheel cylinders?
What about the four soft hoses? Any of them leaking?

And no, the leaking out of the master cap should not cause this. Only a leak below the reservoir (as opposed to the top) will cause sponginess. A leak at the cap is just messy.
Reaaaaaaaaaaaaaaaaaaalll messy if it hits the paint!

Good luck.

Paul

 

[thomasmatthew]

rule of thumb when bleeding brakes is always start with the wheel FARTHEST from the mc working your way to the closest so start with rr then lr then rf then lf

 

[fsharp1]

DirtDonk: It goes to the floor, I manually did them today, Having my wife assist, I've been bleeding with the driver side front ..... Passenger side front........Driver side Rear........Passenger Rear.


Thomasmatthew: I may have been doing them wrong perhaps

 

[TBS-POPS]

Adjust the brakes first before you bleed.

 

[El Kabong]

Just to be sure on the routine, I'll throw in a copy of the 2 Man Brake Bleed below. Did you replace anything else, or just the front wheel cylinders? As they mentioned above, have you adjusted the brakes? Even if it's bled properly, you'll have a low pedal if they aren't adjusted. What was the original reason for working on the brakes?

2 Man Brake Bleed

1-Usual safety stuff (Block the wheels, trans in correct gear, on safe axle stands if jacked up, etc.). -Broncos are high enough you might be able to do this without jacking it up.
2-Check the level of the brake fluid, add if needed. Recheck periodically & add as needed throughout the bleeding process. Do not allow it to run out. If it runs out, you must start over.
3-Have your helper pump the brake pedal a few times & then hold it down. Do not let the pedal up while the bleeder is open.
4-Open the bleeder valve, observe the fluid flowing from the bleeder. Fluid & air bubbles can spray, it's best to run a clear hose from the bleeder into a container. Some would say wear safety goggles. Keep your mouth closed ;D.
5-Close the bleeder valve while the pedal is still depressed.
6-Have the helper pump the brake pedal, observe height of pedal.
7-Repeat steps 2-6 until no bubbles are seen in the fluid from the bleeder valve, then move to the next wheel, following this order: RR, LR, RF, LF. Be sure that each bleeder is closed before moving on. If the brakes are otherwise in good condition, adjusted, & not leaking, the pedal should be firm when done.
8-Check the level of the brake fluid, add if needed. Recheck again soon to be sure fluid isn't leaking.

It's important with brakes to be sure that everything is done right. Safety is vital. Follow the instructions in the manual. If you are not sure about it, work with someone who has good experience with it, or tow it to a qualified shop. Don't drive it until you are sure that it's fixed right.

 

[fsharp1]

Kabong: They went to the floor when I pressed them!
I will say there is NO air left in the lines,

Lesson Two, Bleed then learn to adjust,

 

[nrramse]

Drum brakes have self adjusters that get actuated by backing up and touching the brakes - they're worth fixing if broke.

It might be time for a new master cylinder.

I've never seen it happen, but I supposed a rubber brake line that has a weak spot could cause a spongy pedal. The stainless braided brake lines are a nice upgrade!

Good luck - Newell

PS - Thanks Pappit, that was a funny post

 

[fsharp1]

This site is awesome, Two issues corrected this week just by posting,
Was not aware of the adjusting thingy-majig, Brakes are stopping me now,
Thanks everyone !!!!!!! I feel pretty cool LOL

 

[shamu]

This site is awesome, Two issues corrected this week just by posting,
Was not aware of the adjusting thingy-majig, Brakes are stopping me now,
Thanks everyone !!!!!!! I feel pretty cool LOL

Thanks for the "THANKS"

It is nice that you took an extra minute to say that for the great members on this site whom helped you out.