Individual Liberty — Individual Responsibility 

Well, I managed to pick up the caliper. Then I came home to take the old one off. I used some PB Penetrating Catalyst and waited a bit. The bolts that hold it on are 5/8 inch bolts, and I have just two 5/8 inch sockets. Somehow my 5/8 inch impact socket for my air gun disappeared along with some other tools. Go figure.

Anyway, I borrowed a 1/2 inch breaker bar and a 1/2 inch drive 5/8 socket. Unfortunately the thing is a 12 point socket. I managed to get one of the bolts off. The other one (the one just over the axle) is being a pain in the neck. A bruised thumb, sore elbow and another trip to the parts store to get a six point 5/8 inch socket and I still haven't managed to break it loose. I'm not going to quit though. I will get this car running and stopping safely.

It's supposed to rain tomorrow. The car is still up on jack stands, with the wheels off. I've got a 10x10 popup canopy I'll put over it and work in the rain if I have to. I've put too much time and effort into this not to get it done. If I can't break the bolt loose the "normal" way tomorrow, I'm going to try heat (very carefully, I don't want to burn up my car after all). I have a feeling I'm going to end up replacing the bolt as well as the caliper, but that shouldn't be a problem. Bolts are cheap.

Funny thing is, I don't remember this being so hard to do the last time I changed the brake pads. You have to take the calipers off to do that and I remember it being much easier back then. Maybe it's the difference between using a hoist provided by my cousin's shop and doing it on my back, but somehow I doubt it. Maybe it's just the rust.

This is unbelievable. I'm beginning to suspect that in the entire 32 years that my car has been on the planet the calipers have never been removed. The rotors are the original rotors, riveted to the axle. Changing the rotors generally involves drilling the rivets out. Happily the brake pads have been changed many times.

Contrary to my earlier comment, changing the pads on these older Corvettes isn't that involved an operation. All you have to do is remove a cotter pin, knock a retention pin back and slide them vertically out of the caliper. As long as they're not tight against the rotor that is. You can always open the bleed screws and press the pads back to make the job easier. Putting the new pads in is the reverse operation. The calipers don't have to come off, unlike with every other disk brake system I've ever worked with.

Removing the rear calipers is a major pain. The front ones are a bit easier because you can turn the wheel to get better access to the mounting bolts. Not so with the back ones.

The trailing arm that serves to locate the axle has a raised square metal pad on it that bounces against the suspension stop on a hard bump. This metal pad reduces the clearance on the forward mounting bolt to a minimum. The calipers are cast iron. So is the mounting flange. The bolt passes through the caliper and into the threaded portion of the flange. There's a backing plate just behind the flange to prevent brake dust from getting into the suspension. Beneath the axle and slightly to the rear is a transverse leaf spring. Passing just under the arch of the leaf spring is the exhaust pipe, one on each side. Between the exhaust pipes sits the spare tire in a case to keep it clean.

What this means is there's not a lot of clearance in this area to work with. Knowing that it has been a long time since the calipers were removed, I used some Blaster PB Penetrating Catalyst to try to break the rust free. In the past this has been my friend on a lot of stuck fasteners. I tried using an air gun to remove the bolt. I used a 5/8" socket with 1/2" drive. I also tried using an 18" long breaker bar. The bolt wouldn't budge. The man that I borrowed the breaker bar from is even bigger than I am, and he's also pretty strong. He couldn't break the bolt free either. I tried hanging my weight off of the breaker bar. It still wouldn't budge. Then, believe it or not, I rounded off the straight walls on a six sided deep socket, turning it into a piece of junk. The corners of the bolt are slightly rounded, but it wasn't the bolt that gave way, it was the wrench!

I even went so far as to try leverage. I made certain that my brand new 5/8" deep well socket (the one I bought to replace the one I rounded out) was firmly engaged and tight against the caliper. I placed an 8 foot long two by four over the handle of the wrench and applied as much weight as I could to it. The two by four broke in the middle. The wrench didn't move. The bolt didn't move.

I'm still not done. Tomorrow I'm cleaning everything out to get rid of all of the grease, oil, and other petroleum products. I'm taking an old towel, soaking it in water and wrapping it around the axle. Then I'm going to take a propane torch to the flange the bolt screws into, while a friend works the bolt back and forth with the breaker bar. Maybe by expanding the flange around the bolt it will come loose. Even with all of that, I'm keeping a bucket of water or sand handy to put out any fires that might start. The last thing I want to do is burn my car down to the ground or even to burn the bearing seals.

If I still can't get that bolt to turn, I have one last option I'll try. If it comes to it, I'll use a saw and cut the bolt between the caliper and the flange. Once I have the caliper off, I'll drill out the rivets in the rotor and remove it. Then I'll drill out the remnants of the bolt and re-thread the hole.

There's no way I can safely drive the car with bad brakes, and I intend to drive it. One way or another, I'm going to get that bad caliper off of the car and get it replaced with the rebuilt one I bought yesterday.

I just never thought it would take thismuch work to do it.

Since you'd have to use slightly over-sized bolts once you re-tapped this side, you might consider re-tapping the other side as well, so you have matching bolts on both sides.

Yes indeed, that could be a potential pitfall. Fortunately thread repair kits often include a metallic insert so that the re-threaded hole has the same dimensions as the original. Often a hole rethreaded this way works better to fasten the parts together than the original.

I'm hoping the torch does the trick too. The other option is way too much work.