Question: Brakes Pressure Gone!

[Vette79]

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?

 

[vetteboy86]

I would normally say that murky brown is a sign of moisture in the fluid. However, I have seen tests that have shown moisture content of murky fluid very similar to light amber colored fluid. I guess there are things you can do to verify the moisture content. Either way, I would bleed the rear.

 

[Evolution1980]

Or possibly it has been super heated. Possibly you had a caliper hanging up? Either way, sounds like a caliper replacement may be around the corner.

 

[Vette79]

Thanks, I think the left rear is leaking. I have not ordered parts yet and still researching the possibilities here. Do you have to disconnect the steel brake line to the rear caliper to remove to check for leaking pistons?

 

[Evolution1980]

Someone with more knowledge will chime in here, but I reckon it's probably a good idea if the brake lines still look like they could handle being removed. From what I could see in the pics, the frame looks pretty clean, so I'm guessing your brake lines probably aren't in too too bad of shape. You could always do the quick & dirty inspection by simply removing the pads and checking for moisture around the pistons and brake pad backing.

(It's always easy to recommend how someone else should spend their money , but) I think you ought to probably go in with the notion that you're gonna be replacing your calipers. I've been very happy with the O-ring calipers from VB&P. I got an entire top to bottom brake kit from them. Haven't had a single issue now in 4 years or so of having them. They, like most places, will give you a credit for sending in your cores.

 

[Vette79]

Someone with more knowledge will chime in here, but I reckon it's probably a good idea if the brake lines still look like they could handle being removed. From what I could see in the pics, the frame looks pretty clean, so I'm guessing your brake lines probably aren't in too too bad of shape. You could always do the quick & dirty inspection by simply removing the pads and checking for moisture around the pistons and brake pad backing.

(It's always easy to recommend how someone else should spend their money , but) I think you ought to probably go in with the notion that you're gonna be replacing your calipers. I've been very happy with the O-ring calipers from VB&P. I got an entire top to bottom brake kit from them. Haven't had a single issue now in 4 years or so of having them. They, like most places, will give you a credit for sending in your cores.

Thanks, EVO. I've not done brakes before on a C3 so going slow. Good idea on just removing the pads to check further...

 

[Hib Halverson]

Lots of stuff about 65-82 disc brakes at:
The Big Block from Hell, Part 12
Big Block from Hell, Part 13

 

[Peer81]

Had the same thing last week with my brakes. Removed the pads and I could clearly see one of the pistons was wet. Changed the lip seal and a new dust seal. Took all the air out of the system and the brakes work like new again.

Groeten Peter

 

[Vette79]

Thanks guys, I'm going to pull the pads tomorrow to get a better visual. Probably just going to replace the rear calipers anyways that have stainless sleeves and o-ring seals.

 

[Vette79]

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?

 

[bill81vette]

That's what I put on mine 5 years ago!!
no problems with them since!!!!

 

[Vette79]

That's what I put on mine 5 years ago!!
no problems with them since!!!!

Thanks Bill. I guess I will work with VB&P for parts.

 

[TMPJoe]

Thanks Bill. I guess I will work with VB&P for parts.

Thats what I did to my 1980 last year! comes from a 30 yeard old design and age!!!!!

I used the steel with o rings and I am very happy...

my brother in law wanted me to rebuild the originals but i had too many other "projects" to suffer through!

 

[Evolution1980]

Thanks Bill. I guess I will work with VB&P for parts.

Good call. Contact them via here and you should be able to get some CAC discount.

 

[73shark]

Saw a thread where VB&P has a 15% off sale in August.

 

[Vette79]

Saw a thread where VB&P has a 15% off sale in August.

Placed an order with VB&P for rear calipers and all related hardware. Free brake pad removal tool, installation video, and 15% off. They are the best when it comes to pricing. Can't wait to get started......

 

[Evolution1980]

Placed an order with VB&P for rear calipers and all related hardware. Free brake pad removal tool, installation video, and 15% off. They are the best when it comes to pricing. Can't wait to get started......

Excellent!

 

[Mr. Chuck]

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?

The murky brake fluid spells contamination, which leads to rust / pitted sleve walls, i.e worn / leaking brake piston seals,. Going the stainless route, either w/ sleves or stainless calipers which don't rust, greatly increaand ses their service life and reliability. Did this on my 81 some 40 - 50K miles ago, and no sign of leak or other malfunction. SS calipers are worth the extra cost. I did the front and rear at different mileage, got fronts from Mid-America and rear from Auto Zone. Both have limted life time warranty, can't really say or tell which calipers (brand) are better since nether have given any problems. Hope this helps support your choice in going with SS calipers.

 

[Vette79]

The murky brake fluid spells contamination, which leads to rust / pitted sleve walls, i.e worn / leaking brake piston seals,. Going the stainless route, either w/ sleves or stainless calipers which don't rust, greatly increaand ses their service life and reliability. Did this on my 81 some 40 - 50K miles ago, and no sign of leak or other malfunction. SS calipers are worth the extra cost. I did the front and rear at different mileage, got fronts from Mid-America and rear from Auto Zone. Both have limted life time warranty, can't really say or tell which calipers (brand) are better since nether have given any problems. Hope this helps support your choice in going with SS calipers.

I went with the SS sleeves on new Delco Calipers. My order still has not shipped yet so I'm a little dissappointed with the amount of time it's taking to get the parts. It's been almost two full weeks.

 

[Evolution1980]

I went with the SS sleeves on new Delco Calipers. My order still has not shipped yet so I'm a little dissappointed with the amount of time it's taking to get the parts. It's been almost two full weeks.

Really :eek What did VB&P give as the reason for the delay?