Brake Pressure Gone!
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Joined: Jul 2008
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From: Millersville, MD
Brake Pressure Gone!
OK, the rear compartment for the master cylinder is low and murky. The front compartment is full and clear. No visible leaks or fluid on the floor. The rear left brake caliper appears to be wet so possibly one of the lip seals has failed. The master cylinder and front calipers have been replaced within the past few years. I'll be removing the rear calipers this weekend to visibly and physically check. The brake pedal goes to the floor and the brake light came on but is off now. With the fluid low and murky is that a sign of a leak and air in the system?
Le Mans Master
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St. Jude Donor '14
OK, the rear compartment for the master cylinder is low and murky. The front compartment is full and clear. No visible leaks or fluid on the floor. The rear left brake caliper appears to be wet so possibly one of the lip seals has failed. The master cylinder and front calipers have been replaced within the past few years. I'll be removing the rear calipers this weekend to visibly and physically check. The brake pedal goes to the floor and the brake light came on but is off now. With the fluid low and murky is that a sign of a leak and air in the system?
Murky=old dirty fluid (moisture) that needs to be bled out and changed.
You will probably find bad seals on the calipers. When you change them, I would recommend bleeding out as much of the old stuff as possible before you install the new calipers. (no use running that old dirty stuff through your new parts!) Borrow your S/O's turkey baster and get the old stuff out of the master cylinder first. Refill with new brake fluid. Then bleed the system until the fluid comes out clean and clear. Then install new calipers and bleed again.
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Pro
Joined: Jul 2008
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From: Millersville, MD
Low= a leak and/or worn out pads.
Murky=old dirty fluid (moisture) that needs to be bled out and changed.
You will probably find bad seals on the calipers. When you change them, I would recommend bleeding out as much of the old stuff as possible before you install the new calipers. (no use running that old dirty stuff through your new parts!) Borrow your S/O's turkey baster and get the old stuff out of the master cylinder first. Refill with new brake fluid. Then bleed the system until the fluid comes out clean and clear. Then install new calipers and bleed again.
Murky=old dirty fluid (moisture) that needs to be bled out and changed.
You will probably find bad seals on the calipers. When you change them, I would recommend bleeding out as much of the old stuff as possible before you install the new calipers. (no use running that old dirty stuff through your new parts!) Borrow your S/O's turkey baster and get the old stuff out of the master cylinder first. Refill with new brake fluid. Then bleed the system until the fluid comes out clean and clear. Then install new calipers and bleed again.
Le Mans Master
Joined: Jan 2004
Posts: 7,412
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St. Jude Donor '14
If one is leaking, the other is not far behind. I asked on the forum a long time ago if anyone changed brake fluid as a preventive maintenence task. Nobody did, as I recall. So, that brake fluid in your car has probably been degrading and collecting moisture for years, which has been damaging the seals and calpers and everything else.
But back to your question, if you pull the wheels, a leak at the caliper should be easy to see. Maybe just pull the calipers and take a look before you pull the lines (so you don't introduce fluid from the lines making it difficult to see where the leak actually is).
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Joined: Jul 2008
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From: Millersville, MD
If money is not an issue, I'd replace them both if you never have before.
If one is leaking, the other is not far behind. I asked on the forum a long time ago if anyone changed brake fluid as a preventive maintenence task. Nobody did, as I recall. So, that brake fluid in your car has probably been degrading and collecting moisture for years, which has been damaging the seals and calpers and everything else.
But back to your question, if you pull the wheels, a leak at the caliper should be easy to see. Maybe just pull the calipers and take a look before you pull the lines (so you don't introduce fluid from the lines making it difficult to see where the leak actually is).
If one is leaking, the other is not far behind. I asked on the forum a long time ago if anyone changed brake fluid as a preventive maintenence task. Nobody did, as I recall. So, that brake fluid in your car has probably been degrading and collecting moisture for years, which has been damaging the seals and calpers and everything else.
But back to your question, if you pull the wheels, a leak at the caliper should be easy to see. Maybe just pull the calipers and take a look before you pull the lines (so you don't introduce fluid from the lines making it difficult to see where the leak actually is).
Safety Car
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From: North Easton Mass
Rick B.
Le Mans Master
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St. Jude Donor '14
Which part exactly are you struggling with? Pull off the wheel and take a look if anything is wet. If you are not going to do the work yourself, get it to a shop and they will usually give a free inspectionand tell you what you need.
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Pro
Joined: Jul 2008
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From: Millersville, MD
Only struggle here is with posting pics...Removing just the pads to inspect is much easier so I'll do that tomorrow...Thanks.
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From: Millersville, MD
Left rear inside piston leaking. They look like the original calipers. I'll run the numbers later on the old to be sure but I'm going to replace both rear calipers. Any suggestions? I want the stainless sleeves and o-rings for seals, right?
Le Mans Master
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St. Jude Donor '14
Burning Brakes
Joined: Jun 2005
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From: LaUgH, mOrE!
Also, I found this link with pictures to give tips on how to do it.
Do you guys see many differences from these basic instructions for the '79?
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From: Millersville, MD
I have nearly the same problem... leaky R/R caliper on my '79. All original. I ordered the whole set from VB&P--loaded SS O Ring Calipers, caliper bolts, retaining pins, clips, new lines, brake fluid. I believe they are 15% off right now.
Also, I found this link with pictures to give tips on how to do it.
Do you guys see many differences from these basic instructions for the '79?
Also, I found this link with pictures to give tips on how to do it.
Do you guys see many differences from these basic instructions for the '79?
Burning Brakes
Joined: Jun 2005
Posts: 1,113
Likes: 35
From: LaUgH, mOrE!
They also will send a free "Do it yourself Video" of them doing a '69's brakes. They also included a paper on Torque settings.
But I, like you, do need some folks to chime in here as to the differences on doing a '79.
In July they were also offering free powder coating. You may also want to ask if they'd throw that in since yours started leaking in July. Just trying to help out here.
Thread Starter
Pro
Joined: Jul 2008
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From: Millersville, MD
You may just want to call them and see what they can do for you. I ordered this set. At some point I'll be doing all 4, I'm sure.
They also will send a free "Do it yourself Video" of them doing a '69's brakes. They also included a paper on Torque settings.
But I, like you, do need some folks to chime in here as to the differences on doing a '79.
In July they were also offering free powder coating. You may also want to ask if they'd throw that in since yours started leaking in July. Just trying to help out here.
They also will send a free "Do it yourself Video" of them doing a '69's brakes. They also included a paper on Torque settings.
But I, like you, do need some folks to chime in here as to the differences on doing a '79.
In July they were also offering free powder coating. You may also want to ask if they'd throw that in since yours started leaking in July. Just trying to help out here.
