Brake Fluid
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Naaah!
Don't worry, its only the brakes. Don't need 'em until its time to stop.
Seriously.
Its time to rebuild replace the MC.
Inspect brakes, rebuild all four if leaks are present.
Drain/flush the entire system.
Why this much work?
How old is the car?
When was the last time the brakes were overhauled?
How important are the brakes?
Don't worry, its only the brakes. Don't need 'em until its time to stop.
Seriously.
Its time to rebuild replace the MC.
Inspect brakes, rebuild all four if leaks are present.
Drain/flush the entire system.
Why this much work?
How old is the car?
When was the last time the brakes were overhauled?
How important are the brakes?
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Still..... time for some serious maintenance.
The rear reservoir is a classic warning sign!
Time is short Dude. Git-r-done
The rear reservoir is a classic warning sign!
Time is short Dude. Git-r-done
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Thread Starter
Burning Brakes
Joined: May 2013
Posts: 768
Likes: 24
From: Valrico Florida
No, I thought the overfill condition of the front could be a problem. The rear looks acceptable doesn't it?
I appreciate the info, believe me.
How do I know for sure there is actually an issue though? I don't want to replace the MC for no reason.
I appreciate the info, believe me.
How do I know for sure there is actually an issue though? I don't want to replace the MC for no reason.
Melting Slicks
Joined: Jan 2001
Posts: 2,940
Likes: 5
From: Chesapeake VA
can you tell us what the fluid level change was.
I think everyone is assuming that both containers were full and now the rear one is loosing fluid.
If you do not know the age of the pads and rotors, changing them is probably a good idea. I did not change the front rotors and pads the first 9 years I owned my 86', because they still looked good. Finally, I found a good deal on RockAuto.com for AC Delco rotors and Wagner pads. I don't know if the old pads were cheap or petrified from age or what, but the difference was amazing. Had I known the difference would be that big, I would had done it the first month I bought the car. It still is not as good as the brakes on my C5, but it is a LOT closer than it was.
Also, if it has been 2 years since a brake fluid flush, then you are due.
I think everyone is assuming that both containers were full and now the rear one is loosing fluid.
If you do not know the age of the pads and rotors, changing them is probably a good idea. I did not change the front rotors and pads the first 9 years I owned my 86', because they still looked good. Finally, I found a good deal on RockAuto.com for AC Delco rotors and Wagner pads. I don't know if the old pads were cheap or petrified from age or what, but the difference was amazing. Had I known the difference would be that big, I would had done it the first month I bought the car. It still is not as good as the brakes on my C5, but it is a LOT closer than it was.
Also, if it has been 2 years since a brake fluid flush, then you are due.
Thread Starter
Burning Brakes
Joined: May 2013
Posts: 768
Likes: 24
From: Valrico Florida
Not sure where the levels started at to be honest.
I think I will start with a bleed and refill, note the levels, and then see if they change. At best guess I would think both levels were slightly below max and the rear went down and the front went up but I don't remember really noticing them before to be honest.
The car has 25K original miles, I am pretty sure the pads and rotors are original. Should I just try some new pads first?
I think I will start with a bleed and refill, note the levels, and then see if they change. At best guess I would think both levels were slightly below max and the rear went down and the front went up but I don't remember really noticing them before to be honest.
The car has 25K original miles, I am pretty sure the pads and rotors are original. Should I just try some new pads first?
Le Mans Master
Joined: Jun 2009
Posts: 6,528
Likes: 752
From: South Dakota
My '85 did exactly the same thing. It was a bad master cylinder. It leaked internally. The reservoirs were level and over time they would look like yours with different fill levels.
On mine it would function almost normally. Usual braking you would not notice a problem. The one situation where I noticed a function problem was if you are stopped with your foot on the brake and kept still, the holding power would decrease and the car could roll.
You are due for a master cylinder.
On mine it would function almost normally. Usual braking you would not notice a problem. The one situation where I noticed a function problem was if you are stopped with your foot on the brake and kept still, the holding power would decrease and the car could roll.
You are due for a master cylinder.
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
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St. Jude Donor '16
I would get a turkey baster and remove the old fluid and fill to just below max if the front level increases yes the master is bad. I change my fluid when it loses its clarity its cheap.
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
You need to identify the problem area and consider the system as a whole.
DON'T cut corners on a car twenty five plus years old.
Drifting
Joined: Feb 2008
Posts: 1,537
Likes: 178
From: NE Ohio
2024 C4 of the Year Finalist - Unmodified
Le Mans Master
Joined: Feb 2005
Posts: 6,481
Likes: 566
From: Clearwater Florida
..... I would check the front pads for wear ... the reservoir nearest the booster (rear) feeds the front brake circuit ... as the pads wear , the fluid level slowly drops because the M/C and res are filling the piston in the caliper as it moves closer to the rotor ... when you install new pads you have to push the piston(s) back into the caliper which will transfer the fluid back to the reservoir ... your pic indicates normal levels since the front brakes do at least 80% of the braking and wear out much faster than the rears ......
Thread Starter
Burning Brakes
Joined: May 2013
Posts: 768
Likes: 24
From: Valrico Florida
Ah... thank you for the explanation C409! I am definitely a brake noob. I have always changed my own pads and rotors on my other cars but never really paid attention to the MC reservoirs. I guess in the Vette they are just too noticeable... so I noticed... lol
I don't drive the car much, but I did the fluid transfer and I am going to see if there are any changes over the next couple of weeks of short drives.
Regardless of what I find I will most likely bleed the brakes, change fluid, and put on some new hawk pads to see if I can increase braking performance. My Daily Driver is a 98 Lexus GS400 which has incredible stopping power and is most likely one of the reason the Vette when I take it out feels a little more lackluster.
1985 Corvette 60-0 136ft
1998 Lexus GS400 60-0 114ft
I don't drive the car much, but I did the fluid transfer and I am going to see if there are any changes over the next couple of weeks of short drives.
Regardless of what I find I will most likely bleed the brakes, change fluid, and put on some new hawk pads to see if I can increase braking performance. My Daily Driver is a 98 Lexus GS400 which has incredible stopping power and is most likely one of the reason the Vette when I take it out feels a little more lackluster.
1985 Corvette 60-0 136ft
1998 Lexus GS400 60-0 114ft
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
Le Mans Master
Joined: Feb 2005
Posts: 6,481
Likes: 566
From: Clearwater Florida
..... I stand corrected ... to the OP , check ALL pads for wear ... check for external leaks ... bleed to flush the brake hydraulic system (should be done every couple of years anyway) ... and report back on any unusual braking events that you encounter ..........