[hduff]

I have the infamous '79 Seville rear calipers on my ride. They had seized from sitting too long, so I replaced them and flushed the system.

I'm having trouble getting the parking brake adjusted following instrucstions at http://www.73-87.com/7387garage/chas...n/reardisc.htm (down the page under 'Adjust Caliper Parking Brakes').

Pulling down on the lever offers no resistance, so I'm attempting to follow step #2 from that page with no success. The shaft wants to screw itself into the caliper body; if I hold the shaft outby the nut, the shaft just spins freely.

What to do?

[Frisco]

I have attached this PDF file before and found it to be helpful adjusting the GM disc brake calipers with the built in parking brakes.

[hduff]

Originally Posted by Frisco

I have attached this PDF file before and found it to be helpful adjusting the GM disc brake calipers with the built in parking brakes.

Thanks. I guess I have just not pulled on the lever enough.

I'm beginning to hate these brakes.

[Frisco]

Originally Posted by hduff

Thanks. I guess I have just not pulled on the lever enough.

I'm beginning to hate these brakes.

I used them on my coupe because the brackets and discs were there when I purchased the unfinished coupe. I mistakenly thought having 4 wheel discs would be a great way to go.

I do NOT recommend this style (with the built in parking brake by GM) of rear calipers. If you really want rear discs that work and are much easier to install, use the front calipers (the mounting bracket is the same as used for these calipers) and manufacture or purchase a parking brake that attaches to the third member.

Had I known how much of a pain they were to get adjusted and keep them that way, I NEVER would have gone that route. You MUST use the parking brake to keep them adjusted. I had to make a lever to increase the mechanical advantage to enable the short Lokar emergency brake handle to be able to apply enough force to engage the built in parking brakes. I posted this info on this site in the past. The stock drum brakes on the 9" rear are more than sufficient and MUCH cheaper and easier to set up and service.

[hduff]

I found this link which details the inner workings of the brakes (mostly on page 2):

http://classicbroncos.com/reardiscs.shtml

What a complicated mess.

IIRC, some states don't allow third-member parking brakes. From what I've read, the better design is the later GM discs that essentially use small drum brakes inside the disc rotor as the parking brake. I believe that this is the design inspiration for the Wilwood brakes.

[Rickracer]

You'd be money and time ahead to just trash that whole system and switch to later model S10 or Camaro rear brakes with the disc/drum system. They work VERY well. I've got Camaro "LS" brakes on the front of my S10, and 2000 Blazer discs on the rear, and riding in my truck, if you're not strapped in, I can make you kiss the windshield,
I contemplated using the Camaro LS brakes on the rear of my truck as well, but the S10 brakes were a much better balance with the strong front weight bias of the small pickup. The rears only lock up in an all out panic stop, and even then, only when the front brakes have caused significant weight transfer to the front, then the RABS system takes over and modulates the rear brakes,
In a sedan, the Camaro rear brakes would likely be a better solution.

[Maxwell007]

Everyone is entitled to their own opinion but I wouldn't throw away your brake system just yet. True...these calipers do have some issues but they can be made to work.
To adjust a balky caliper, try this-
1. Attach a large adjustable wrench to the parking brake arm (this to give you plenty of leverage).
2. Turn the arm to apply the parking brake.
3. With the brake fully applied, hold pressure on the arm and put the flat end of a large screwdriver into the groove cut on the disc piston. (the dust boot fits into this groove but you can still grab the lip of the groove with the screwdriver)
4. Apply some pressure on the groove with the screwdriver toward the rotor. (What you are doing here is trying to apply the brake by prying the piston with the screwdriver).
5. With pressure still applied on the screwdriver, return the parking brake lever back to it's relaxed position.
I have been a brake salesman for a major brake manufacturer for over 30 years and learned this technique from a customer of mine years ago. What you are doing is forcing the adjuster to move. After doing this, if you will use your parking brake regularly, you shouldn't have any more problems.

The post that you referred to is not entirely correct. It says not to use rebuilt calipers since they do not have new pistons. I do not know for sure about others, but ours all have new pistons and new hardware included in the rebuild. I don't even know where you would find a new caliper since they are so old. I am sure no one makes new ones anymore.

Anyway, sorry to ramble, but try this and see if it helps. I've done this many, many times before and it usually works well.
Good luck.