No Brakes and I need help
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
No Brakes and I need help
Hi all,
My 79 has been in storage for tha last three months and I just got it going again taday, But as I was driving it the brakes started getting real spongy and eventually went to the floor. Now I have little to no brakes and the brake light is on. What should I look for first? Has anyone had this problem? and if so what is the remedy. Any help would be great.
Thank You.
My 79 has been in storage for tha last three months and I just got it going again taday, But as I was driving it the brakes started getting real spongy and eventually went to the floor. Now I have little to no brakes and the brake light is on. What should I look for first? Has anyone had this problem? and if so what is the remedy. Any help would be great.
Thank You.
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
I checked for leaks at each wheel but found nothing. When the breaks first started to get spongy I checked the fluid and it was low so I added a little. Then they went to the floor. I checked the fluid again and it wasn't low but looked cloudy. What else could make the pedal go to the floor if there are no leaks?
Drifting
Joined: Oct 2004
Posts: 1,259
Likes: 7
From: Ontario
so many things.. but likely a caliper as per the above post. A very small leak will do this.
Could also be rusted out line, ruptered flex lines, degraded caliper piston seals, bad master....etc. Once you find and fix the problem it sounds like you also need to bleed in fresh fluid.
If you are not someone comfortable/experinced with brake systems you might consider a toe to a garage given the safety issues here.
Could also be rusted out line, ruptered flex lines, degraded caliper piston seals, bad master....etc. Once you find and fix the problem it sounds like you also need to bleed in fresh fluid.
If you are not someone comfortable/experinced with brake systems you might consider a toe to a garage given the safety issues here.
Racer
Joined: Mar 2008
Posts: 428
Likes: 0
If your fluid level is down, I would suspect a leak in the system. Do you have any inside side of tires showing signs of fluid leakage, lines that look like the're from the center outwards from centrifugal force?
If you pump the pedal, will it come up at all?
If you pump the pedal, will it come up at all?
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
I checked each wheel on the inside and there is no fluid leaking and all the lines look ok. It does looke like there is fluid around the bottom of the master cylinder leaking down the booster. If the master cylinder goes bad will it cause this problem? I just have a gut feeling that it's the master cylinder. How can I check it?
Racer
Joined: Mar 2008
Posts: 428
Likes: 0
I checked each wheel on the inside and there is no fluid leaking and all the lines look ok. It does looke like there is fluid around the bottom of the master cylinder leaking down the booster. If the master cylinder goes bad will it cause this problem? I just have a gut feeling that it's the master cylinder. How can I check it?
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
A cheep test!
Pull the master clyinder off and try to bench bleed it. A bench bleed kit is about $5.00. If you see a lot of fluid leaking out of the rear than the seal is shot. That would be a good place to start. PG.
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Thread Starter
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
Ok I've done brake lines and calipers but I have never pulled a master cylinder. Do I have to pull the entire booster with it or can I just remove the master cylinder and if the seal is blown on the master would that cause the problem? Sorry for all the question but I am trying to understand how it all works before I tear into it.
Thanks
Thanks
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
If the rear seal on the MC is leaking you will see the fluid coming out as you beech bleed it. If you step on the brake pedal and the red light on the dash comes on it is telling you that the pressure is out of balance, a check of the MC is a good place to start without replacing everything and spending money on things that don't need to be changed. PG.
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
First, make sure the leak is not coming from the cap on the MC. I found fluid leaking down the firewall and thought I had a big problem and all I had to do was replace the gasket on top of the MC lid. If that's not it, I'd bench bleed it and see what result you get.
Also, when you added fluid was it the same as the fluid already in the system? I don't think you are supposed to mix them...
Also, when you added fluid was it the same as the fluid already in the system? I don't think you are supposed to mix them...
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Good Point!
Dantana brings up a good point, the seal on top of the MC can leak, I had to change mine , I would loose about 1/4 of a inch every few weeks untill I changed it, but if you still have fluid left I would still bleed the MC and see if it leaks since your getting a red light. PG.
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
I don't know if it was the same fluid. It's very possible that the gasket around the MC bowl is leaking but would that cause the brakes to stop working? I want to Thank all of you for your help. I have a lot of good info to help me get started so first thing tomorrow I'll dive in and hope I don't drowned. If you think of anything else let me know and I'll keep checking my post.
Thanks again.
Thanks again.
Racer
Joined: Mar 2008
Posts: 428
Likes: 0
Ok I've done brake lines and calipers but I have never pulled a master cylinder. Do I have to pull the entire booster with it or can I just remove the master cylinder and if the seal is blown on the master would that cause the problem? Sorry for all the question but I am trying to understand how it all works before I tear into it.
Thanks
Thanks
A new master must be bench bleed before installing it and then the system must also be bleed by gravity, a friend pumping up the brakes and holding it while you crack open the bleeder or with a power bleeder.
Also, don’t be sorry for the questions, just keep asking.
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
I had this same issue with my car after it sat for a few months. One caliper, although it wasn't leaking any fluid, it was sucking air in past the piston seals. I'd bleed it, get out all kinds of air -- then, as I drove the car, the pedal would get lower and lower as I used it.
Find out which caliper it is by bleeding the brakes. Replace or rebuild that caliper, and you should be good to go.
Find out which caliper it is by bleeding the brakes. Replace or rebuild that caliper, and you should be good to go.
Instructor
Joined: Apr 2007
Posts: 206
Likes: 0
From: Bardstown Ky
if/when you decide to replace the master, a couple'a things need to be made note of.
*bench bleed. saves a lotta time and trouble.
*check new part against old part; do not turn in old part for core UNTIL the job is complete. look inside the piston bore-area (the section which rests inside the booster) to ensure both pistons share the same length in the master. this will tell you if the old pushrod will work or not in the new master. pushrod length is crucial to how the replacement part works or not.
*you'll have to bleed all the calipers. air has been induced into the system, and the brakes won't work until all the air is out.
as Project80 said: "keep asking". there's plenty of us been down the C3 bad~brakes road on here !
