Brake pedal going too far down....
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Brake pedal going too far down....
Hi guys. I haven't run my car in a long time. It's sat for about 6 months. Today when test driving it around, the brake pedal was going about 1 1/2" from the floor when I tried to stop. The pedal would be about 2" and feel more normal if I pumped it once prior to steadily pushing the pedal. Vacuum is steady at about 17 which is normal for my car. Do I just need to flush the brake fluid? It feels like the pedal is firm once depressed, so I don't think it's the master cylinder. What do you guys think? Thanks!
Le Mans Master
Joined: May 2000
Posts: 7,033
Likes: 12
Hi guys. I haven't run my car in a long time. It's sat for about 6 months. Today when test driving it around, the brake pedal was going about 1 1/2" from the floor when I tried to stop. The pedal would be about 2" and feel more normal if I pumped it once prior to steadily pushing the pedal. Vacuum is steady at about 17 which is normal for my car. Do I just need to flush the brake fluid? It feels like the pedal is firm once depressed, so I don't think it's the master cylinder. What do you guys think? Thanks!
I doubt flushing will help. I guess you could try to bleed the brakes though. Otherwise I would guess the cups in your MC probably took the large dump.
Race Director
Joined: Jun 2004
Posts: 13,960
Likes: 707
From: WI
If you pump the pedal and it is then normal, that would be the master cylinder bad. You could try bleeding the brakes just in case there is a ton of air. If you do, check the front and back pads. If the front seal in the master is bad the rear pads will be much more worn due to the front not working as well.
Melting Slicks
Joined: Apr 2002
Posts: 2,118
Likes: 0
From: St. Charles, MO Route 66 Corvette Club
qwiketz: I would try flushing the brakes (this process also removes any trapped air in your hydraulic system) and replace with new fluid. This is a relatively easy procedure and will not cost you much $$$ to perform. It may solve your problem. While you are doing this process, examine the MC and all four calipers for any sign of fluid leakage. If you find leakage, that component has a problem.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
qwiketz: I would try flushing the brakes (this process also removes any trapped air in your hydraulic system) and replace with new fluid. This is a relatively easy procedure and will not cost you much $$$ to perform. It may solve your problem. While you are doing this process, examine the MC and all four calipers for any sign of fluid leakage. If you find leakage, that component has a problem.
If it wasnt doing this at all before you put it away, and it started pretty near as soon as you took it out after 6 months, then there is a reasonable chance flushing may fix it.
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
First check for leaks in the system.
Then, try to hold steady pressure on the brake pedal....if it slowly sinks, then it's a bad MC.
I doubt that flushing will cure the problem, certainly not permanently.
I say that because there are millions of cars with 15year-old brake fluid in their systems that don't exhibit this problem.
However, IT CERTAINLY WON'T HURT ANYTHING!!!!!
Good Luck!
Larry
code5coupe
__________
I ain't easily impressed....
Then, try to hold steady pressure on the brake pedal....if it slowly sinks, then it's a bad MC.
I doubt that flushing will cure the problem, certainly not permanently.
I say that because there are millions of cars with 15year-old brake fluid in their systems that don't exhibit this problem.
However, IT CERTAINLY WON'T HURT ANYTHING!!!!!
Good Luck!
Larry
code5coupe
__________
I ain't easily impressed....
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
hey guys. thanks for the input. The car's rear brakes are barely working; just enough to hear them scraping the rust off the rotors. They won't even hold the rear wheels stopped on a smog dyno. The pedal doesn't sink; it's firm once depressed if you hold it. The fluid in the brakes is more than likely 8 years old. I never changed or flushed it yet(I was waiting to install the drm spring) and I seriously doubt that the prior owners did since the brembos up front were installed. I've got a half day today and plenty of time this weekend, so I'll get on it. How much is a new MC?
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Flush it for christ sake. It shouldve been done at least 6 years ago. Its probably full of water and sludge which CAN AND WILL cause what you describe.
Youll probably find when you do flush it youll have other issues come up over the next few weeks cause youve failed to correctly maintain it. You might be lucky, but youd better pray!!
Youll probably find when you do flush it youll have other issues come up over the next few weeks cause youve failed to correctly maintain it. You might be lucky, but youd better pray!!
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Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
yup, I was going to flush the brake system when I was going to install the drm spring. I got the drm spring about a year after I bought the car. Since then the brakes have been mostly unattended to and that project took a back seat to me selling my other car. I need to get on it. I'll do a search on bleeding brakes this afternoon. That's one of the reasons why I took a little longer to get this done; I've never done it before. I'm sure it's pretty easy though based on what people have said.
