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Life Long Opeler
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Discussion Starter #1
In an earlier post, I stated that there was a grinding noise when it rolled and it was REALLY hard to push. Well, I took one of my wheels off today and it looks like the brakes are actually depressed against the disc. I went and played with the pedal but nothing. I need to take these things off anyway to inspect them and turn the disc, but is there any reason why it's doing this and what do I need to do to correct it?

P.S. I'll take a pic of how crappy they look a little later and get it up here.
 

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Life Long Opeler
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692 Posts
Discussion Starter #2
GOT IT!!! However..................

Well, I unscrewed all of those star pattern bolts and the brakes came loose..............uh.............except for one. Dang, it always has to be one. Top one on the passenger side.

Well, now I've gone and stripped the dang star pattern trying to get this stupid thing off. I was thinking about drilling the thing out, but before I did that, I thought I get your opinions.
 

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Brake Stuck

Sounds like a brake rebuild is about to happen. One of at least two problems are likely.

First, the caliper is seized, which often happens when a car is stored for an extended time, due to absorbed water in the brake fluid corroding the caliper bore and/or piston. The bad news is that both calipers are probably corroded a bit, as are possibly the rear wheel cylinders and the master cylinder. Might require the removal and reconditioning of all, and replacement of the brake fluid. At very least, remove the seized caliper and inspect the bore and piston. And of cource replace (and flush) the brake fluid.

Second possibility is the brake flex hose on that wheel has collapsed internally, which causes it to act like a check valve. I have heard of this but never actually experienced it myself. This requires that the hose be replaced (which might be a good idea in any event ) even if the outside of the hose doesn't appear to be cracked. This also applies to the flex hose for the rear axle.

There has been much discussion here on the merits of DOT 5 brake fluid (silicon based, no water absorption) versus standard DOT 3 and 4 (glycol based). No real consensus, except that they probably shouldn't be mixed, and that silicon-based fluid should probably only be used for brand new seal materials (NO old rubber parts). But DOT 3 fluid works fine in the real (non-racing) world, but MUST be flushed and replaced at least every 3 years, or more often in humid climates.

HTH
 

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Brake Star Bolts

Did you remove the star bolts that fasten the two halves of the calipers together? Did you remove the calipers themselves first(two big bolts that attach each caliper to the hub)? Generally, you NEVER dismantle the calipers, because it is very difficult to get them to seal again. When a professional brake shop rebuilds calipers, they try to leave them intact and only clean up the bore and replace the piston and seals.

If you have gone this far, keep going. You might have to drill out the bolt now, but there should be a nut on the other side that can be split more easily (there are on three of my calipers that I just looked at). The star bolts can be replaced by allen-head bolts and nuts, which should be available from a commercial fastener supply or possibly from a brake re-builder. Good luck.
 

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Life Long Opeler
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Discussion Starter #5
Thanks.

This doesnt sound like fun, especially I've never done a brake job myself. Sounds like it might be a good idea for me to do some of it and then take it to a brake shop for the rest of the work.

Is this kind of stuff very hard?
 

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Voodoou,

You probably won't need to go to a brake shop. But it sounds like you need new (rebuilt) calipers, rear wheel cylinders and hoses.

The calipers are held on by two "regular" bolts, not star bolts. These two bolts are on the inside-bottom of the caliper... the ones that bolt the whole caliper to the "axel-upright'.

If you've taken apart the calipers, don't try to rebuild them yourself. It's not worth the effort nor risk (to the car and your body) to try it. Simply put the calipers back together as best you can and use them as "cores" for new (rebuilt) calipers. You can get all the stuff you need from OGTS. Rebuilt calipers are $99 each (+ $30 each core charge if you don't send back your old core.) I think the calipers come with new pads and "hardware".

It's also not worth turning the rotors. New ones are $38 each. Add in a new pair of front hoses ($33) and you've got a good, reliable, safe front brake system for about $300... and it's all bolt on. The equivalent from a brake shop will cost you much more.

While you're at it, do the rear brakes. New rear wheel cylinders, shoes, and hose will cost about $150. If the drums are still serviceable, have them turned because new drums are a little "pricey" (about $140/pair). It will probably cost less than $50 to have the drums turned.

The whole cost of about $500 plus a couple of week-ends cussing may seem a bit expensive, but have you priced body & paint shops... or emergency rooms lately?
 

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Life Long Opeler
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692 Posts
Discussion Starter #7
What are the star bolts then???

I have four start bolts on each brake. Two at the top and two at the bottom. I took all four out on the drivers side and the caliper came apart. Not totally, but enough where it took the pad off of the rotor and I could turn the wheel. When I took off the last one and spread the thing apart, some break fluid drained out on the floor. I see that I still have a couple of pins that look like it is holding the thing together, and from what I read, Ill need a 1/8 inch flat punch to get those puppies out.

So, what your telling me is that there are two more bolts in the inside somewhere?

Would you like me to take a pic of what I have so you can see what Im talking about?
 

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If you look closely at the caliper and then look at the back of the wheel hub, you will see one bolt at the top and one at the bottom. They are either a 13mm or a 15mm hex (forgot which) those are the ones that you take out to remove the caliper. If the cailper is frozen, you may be able to free it by taking a small pry bar and push the pads back. Loosen the bleeder first. then you should be able to lift the caliper assembly off the rotor.

I had the "check valve" hose happen to me once. I must have hung the calipers by the hose and it stretched it. It would let the fluid go in one direction only and the caliper would hang up.
 

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This is the view from the inside... looking out from the middle of the car so to speak. This view also shows the proper orientation of the caliper (verticle) with the bleeder screw at the top.

Note that these are aftermarket '75 Manta calipers but they are a bolt onto the GT.... through the two mount holes shown. Also note that these aftermarket calipers are assembled with regular "hex" bolts rather than the "star" bolts.

Sorry about the poor quality of the pics, but they were a hasty way to show the mount holes... and in this case, a picture is worth more than 1000 words.
 

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Picture

I really love the value of a picture to explain a point!
One more thing to consider if you are going to order new calipers and rotors anyway should be the "Big Brake Package" OGTS sells. Not much more $ and better stopping, especially if you are getting new parts anyway......
Just wanted to remind you to think about it!
 
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