What happened to the brakes???

[Wolverine]

I had to move my Vette last night so I decided to take it out for a little spin (clear and dry in Michigan!) Its been stored since Dec. 1. Everything seemed fine until I braked hard for a yellow light. I hit it pretty hard, but the car didn't want to stop very quickly. I went home and removed the master cylinder cap and found that the front reservoir was real cloudy, but the back one was clear. I am guessing that this is a symptom, but I don't exactly know what it means.

The brakes are not grinding, they don't seem to be leaking, and there's no abnormal play in the pedal . The last time I had the car out in November, I skidded to a stop from 50 MPH to avoid being hit. It was sure responsive then.

Any ideas?

Brian

 

[Eric]

I'd start with flushing the entire system just to be safe. If you did make a really hard stop there's a possibility that the system heated up and you could have some bubbles in there along with a little water brought in by the heat. While the car was sitting the contaminants may have worked their way up the system. That's just one possiblility but a flush is cheap and may be all you need.

Click here to see another thread about a similar problem. Good Luck!

 

[69MyWay]

Brian,

Chances are you do have a leak. You will have to look on the inside of the front tires and look for streaks of shinny stuff streaming out from the center of the wheel.

 

[Wolverine]

Thanks, guys.

You can probably tell from my post that I don't know much mechanically. Maintaining and fixing my Vette has been an interesting challenge, but so far I've managed to avoid the shop. I've muddled throug quite a bit this past year.

Is bleeding the brakes something that a novice can do without getting into too much trouble or does this require speciaized skill/equipment? I like to do this stuff myself - but this is something I wouldn't want to screw up.

Brian

 

[Nut]

Brian,

Bleeding a Vette is not hard to do. There are a number of different ways from pressure bleeding (where you'll need a helper) to just gravity bleeding (letting the fluid flow by gravity) that you can do yourself. But always keep a check on the Master Cyl resevoir and not let it empty out or you've just added more air back in. I'm sure there are plenty of previous postings on the step by step instructions that someone can link you to.

Good luck. ........ Nut

 

[barrier5]

2 cents more,You most likly have a leak and may need to go as far as pulling the calipers to see,look for wet dust seals,then it were me, I'd use silicone fluid as it doesn"t absorb moisture but it isn't cheap.

 

[Black72]

Weak Brakes

Wolverine,
Just my 2 cents of advice also, but could you possibly have a leaking pwr. booster?
All good advice above, just thought I'd mention something I ran into w/my '72.
Good luck, Mark
PS
When you're working on the car, remember to count to 10!

 

[Eric]

Now that I think about it, I have a leak myself as many other members have heard me whining about for the past 4 or 5 months. Look for a leak first, hopefully it'll be easy to find like mine was when I saw the gunk on the wheel (like Chris said) but either way, you'll want to flush when it's all over. I've been searching for a post about bleeding cause I know I've seen one - maybe I should just break down and type it all out:eyerole.

One question, did the brake light come on when your petal went down? If so, the proportioning valve sensed a pressure loss in one part of the system and shut that part down (front or back).

- Eric

 

[ROCKO]

brakes

If my memory serves me right you have the old style 4 piston calipers which when working fine were great but were prone to leaking. The fix came from the after market by installing stainless steel sleeves in the calipers which stops corrosion and leaks. When i lived in the midwest I was always fighting leaks until I replaced the calipers. A set is about $400.00 plus pads, fluid and etc. Anytime you replace brake pads you should have the rotors turned your you could get poor brake life and brake pedal pulsating. But stainless brakes are a good cure.

rocko

 

[vigman]

Go Stainless

I had been F*&^ing around with my brakes for EONS... replace some seals here, caliper there... to no LONG term avail.

2 secrets here.

Replace ALL the calipers & hoses at once including the two metal lines at the trailing arms for the rear calipers.

POWER bleed
Pressure style ONLY.
KD makes a tool which straps on top of the master, it's a plate that you hook up to your air compressor with a outboard regulator
( about 12 psi ) AND MAKE SURE YOUR AIR IS MOISTURE FREE.

The power bleed pressurizes the system..pushing the 4 calipers out as you bleed. Bullet Proof bleed every time.

The bad news..if your not quick you can run out of fluid in a hurry.

My 73 stops better than my 88 now, now if I only get my master brake booster to work properly.

Mike

 

[Bullitt]

Anytime you replace brake pads you should have the rotors turned your you could get poor brake life and brake pedal pulsating.

I don't think this is necessarily true. Shortened pad life and irregularities are due more to improper bed-in of the pads. If the rotor is within spec and there are not huge wear pattern differences, removing material from the rotor will adversely affect stopping distances. If there is a negative wear pattern, the rotor should be replaced anyways. Removing material also accelerates the heating of rotors during hard stopping or panic situations, because factory cooling vents can only do so much. It's a choice between sacrificing the rotor or the pad. Keep in mind that the pad was designed for a limited life span. Considering the rear run-out issues that Shark owners must deal with, I would think this practice should not be the norm.

--Bullitt

 

[ROCKO]

turning rotors

Bullitt brings up a good point on the rotors. However my suggestion was made as a general practice not a given one. I've learned that putting new pads on rotors that may be not running true have given me poor pad life. Plus resurfacing the rotors should provide a good surface for the new pads. If specs alow it machining the rotors is fine, but there is nothing like new.

Rocko

 

[widewhites]

flushing the system..........what I use

I am glad to hear I was not the only one having all these problem. My 79 went through almost everything mention above. Leak here, leak there, air in the system through the dust seals, which you can't see until you take the caliper off, bad lines and so on. IMHO, best thing to do when you have these problem is replace the caliper and pads. Rebuilding is a gamble. I learned this the hard way. Anyhow, Wolverine, I was not to familiar with the Corvette braking system, but you'll learn.

About flushing the system. I am cheap. So I created my own fluid flushing apparatus from a website I found some time ago. Works good.

Get a jar (I used a ragu sauce jar) with a metal lid. 2 3/16 hoses, one 2 feet , the other 1 foot (or one longer than the other, the length does not really matter). Drill two holes in the jar lid, one on each side of the lid. Use a drill bit the size of the hose, so they go in tight. Insert the 1-foot hose into the jar through one of the drilled holes, far enough to reach the bottom. Insert only the tip of the other hose in the other hole. Next use JB Weld on the outside of the hole/hoses to prevent any air leaks and to keep the hose from being pulled out. This creates a vacuumed jar when you suck through the 2-foot hose. Insert on end of the hose to a bleeder screw and open, then you suck the air out of the jar through the other (2 foot hose) and you will see fluid coming out. Be sure to have someone keep an eye on the master cylinder and full of fluid. Hopefully this makes sense. It works well for me. I only use it for flushing; it does not work well for bleeding. Once the fluid is flushed then I gravity bleed. Hopefully this makes sense. If you need to see it I can post pics.

 

[Bob Chadwick]

If you have to replace the calipers, make sure you shop around. The prices are on a broad range. I did not and paid 3 times what I could have paid for them.

Bob

 

[JHL]

I just ordered my third rebuild kit for the fronts in as many years, I have already got callipers with s/s inserts and it doesn`t seem to make much difference so I`m reluctant to replace them. I have one of those Mytivac pumps but I found the best way if a little time consuming is to gravity bleed them.

IMHO C3 brakes are poor design, fine when they work but in my experience thats not very often, I`m surprised GM got away with it for so long and I would beware of cheap rebuilt callipers, you only get what you pay for.

J.

 

[Bullitt]

I think the leaks are more attributed to the design of the stock and replacement seals. The S/S inserts are more to protect from dielectic corrosion between the cast caliper and the aluminum pistons. My brake pistons looked as if a radioactive rat chewed on them. Has anyone tried the O-ring seals and pistons, available through most Corvette mail-order dealers? Some are touted as a race-design, but anything that's better than the factory is something I'm willing to give a shot.

--Bullitt

 

[Wolverine]

Thanks for all the good advice, guys. As usual, you were all right about the leaking calipers. I took the front wheels off this weekend and it's pretty clear that they both are leaking. One leaks from the top and there is brake fluid dripping onto rotor. This explains why it sometimes pulls to the right when braking.

It sounds as though rebuilding is a gamble. The previous owner had them rebuilt two years ago. I guess I'd better get new ones.

I have three questions:

Where is a good place to order them and what is a reasonable price?

Is it best to go with AC Delco or are there after-market brands that you would recommend?

The pads aren't worn much at all. Is it ok to put them back on, or should I get new ones? If I get new ones, what tpes are least likely to squeak?

Thanks again for all your help.

Brian

 

[69MyWay]

Brian,

Try www.vettebrakes.com


I think you will find the price they charge for the O-ring replacement caplipers is very reasonable. Very nice people, and they can answer your technical questions.

I think you will spend around $350 for the whole set.