handbrake adjust (c900)

Ok, in absence of a reply, and also due to the fact that the townsendimports.com technical documents are currently offline, I decided to try to figure it out myself. And after a couple frustrating hours of adjusting and testing, I can now say that I have failed.

I tried adjusting using both the piston adjusting screw and the cable adjusters under the rear seat. Using the piston adjusting screw: I was unable to find a setting where the rotor could spin freely with the parking brake off and yet still be stopped when the parking brake was applied. I.e. if I tightened the screw enough to make the parking brake work, the pads would drag on the rotor when the parking brake was off. Adjusting the brake using the cable adjusters gave essentially the same problem.

I'm sure this is a simple matter, as changing brake pads is obviously a routine thing. So what am I missing here?

Thanks,

John

That's strange. I didn't answer because I don't have any ideas beyond what you stated.

Is anything stuck? Does the caliper slide properly?

Not sure yet. Do the brakes work with the pedal? Spin the wheel, have someone push the pedal down, does it stop? Let's figure out if this is just a e-brake thing, or a caliper thing altogether?

Dave

Dave,

Thanks for the reply.

I think that it's ok; I cleaned it when I replaced the pads, and it wasn't very dirty or rusty to begin with. I might take it apart again lube the guide pins (although Bentley states that no lubrication is specified for them). Also (and if this statement excessively complicates matters, we might choose to ignore it for now), I found at one point that I was able to lock the rotor by pushing the parking brake lever with my hand, while moving the lever by pulling the parking brake did not seem to work. Which makes no sense (I could see the lever moving quite nicely with parking brake applied).

I was doing this by myself, but I found that when I propped back the pedal with my heavy toolbox, I was unable to spin the wheels. Although of course the amount of force it takes to turn the wheel by hand and that required to stop a moving car are two entirely different matters.

The car seems to stop without difficulty when driving, although I'm not sure that means much since we're talking rear brakes here.

John

Firstly slacken right off both handbrake cables and make sure that the arm that the cable operates on the calliper is all the way back, that is so the stop on the arm is resting against the mills pin, [roll pin if american]. Adjust 4mm allen screw in the back of the calliper until the pads lock the disc and then back off until you can only just turn the disc. Check that the handbrake is working by pushing the arm forwards. Get an assistant to operate handbrake lever to check that the cables are not siezed then adjust to fit, DO NOT make to travel too short otherwise the rear callipers will not self adjust, 4-6 clicks on the lever is fine. HTH Tom, Saabtech.

Tom,

Thanks for the reply, which I think will be quite helpful. One thing you mention which I find interesting: you say to back the piston off until I can only "just turn the disc." The Bentley manual says something like "until the disc turns freely," meaning to me "no contact at all with the brake pads."

So do I understand you correctly that the pads should be dragging (lightly I suppoose) on the disc? This would definitely make the handbrake adjustment easier.

Also, what of the Bentley manual's talk of adjusting the handbrake cable such that the levers do not spring back quite all the way to their stops?

Thank you,

John

Interesting development:

While parking this evening, I momentarily forgot that my handbrake didn't work, and I pulled on the lever. Surprisingly, there was resistance after 3 or 4 clicks. So I put it in gear and tried to move the car, and the handbrake held the car in place rather well! How is this possible? It didn't work when I tested it two days ago, and I've done nothing but drive a few miles since.

Anyway, I suppose I'll jack it up and make sure the brake aren't dragging, and if not, declare it fixed. But regarding that point: should I accept any contact between the pads and the rotor when the brake isn't applied? Or is very light contact acceptable?

John

It self adjusts.

-Fred W

... an impressive and highly welcome feature. How does it work? My interest is strictly academic at this point.

John

I dunno how it works on a SAAB to be honets, but have read that there is one. On most other cars there is a ratcheting affair (star wheel) that takes up the slack each time the brake is operated beyond a certain amount.

-Fred W

Ok, I think I've got everything figured out:

When I replaced the rear pads in the first place, I think I failed to properly clean and lubricate the calipers. Due to my relative inexperience with brakes, I didn't clean and lubricate the areas on the calipers where the metal parts of the brake pads need to slide. Also, I didn't clean or lubricate the guide pins.

And so I took everything apart again, and cleaned/lubed the critical areas. After this, I found the brakes to be much easier to adjust. In fact, I got the brakes AND parking brake working nicely without much trouble at all.

Thanks everyone for your help.

John

John I do believe that the parking brake will self adjust. I had brakes done and the hand brake was all the way to the top. Each time I used it it tightned a little more until after about a month it was normal. good luck papa