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J

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Discussion Starter #1
My parking brake has stopped being useful (and I need it on my T56 car). The pedal locks, and disengages with the lever, but the car will roll. It used to work fine. Any suggestions on where to start? I will be swapping the "storage" wheels for the 18s tomorrow or Monday, so I will have the chance to take a good look...
 
M

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Assuming everything is in good working order, I'd suggest adjusting the parking brake shoe.

I believe you need to remove the rear rotors and adjust the actuating drum for the parking brake shoe.

There is a toothed ring that you'll see that sits in the parking brake shoe's circumference.

It's a little trial and error but it works; adjust the shoe/actuating drum with the parking brake off, install the rotor and rotate it, remove the rotor and re-adjust until the rotor can't turn anymore. Finally remove the rotor and back the drum down a couple of notches.

Lastly re-install the rotors, brake assembly then test the parking brake by activating it and seeing if you can rotate the axle/lug nut studs/rotor assembly by hand.

HTH
 
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Discussion Starter #3
Their was a nice thread on adjusting the parking brake, but I cant find it.
 
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I posted the instructions several years ago, but SEARCH won't pull it up. I can re-post it.

NOTE--Comments below revised 7/11/06

Per the FSM, the "notched wheel" (Adjuster Nut) inside the park brake unit is used to achieve the proper OD of the brake show. The Adjuster Screw threads into the body of the Adjuster Nut, and what you are actually doing is adjusting the threaded portion to create a spec clearance between the shoe and inside of the brake rotor.

Rough adjustment of the park brake shoe can be done by moving the shoe out of position to clear the Adjuster Screw so it can be rotated. If the adjustment is already close, just rotate the screw 180 degrees and re-check the adjustment.

There is a special tool (a gage) that is used to set the dimension, but in the field, no one is likely to have that tool. PBR does have some specific recommended limits to how far you can take the adjustment. The nominal dimension of a properly adjusted shoe against a NEW rotor is 190mm, or ~7.48", and the max adjustment is about 5mm, with a minimum shoe lining thickness of 1.5mm--after that, replace the shoe.
 
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Thanks Bill! I searched (of course), and didn't find anything. I wonder how Hack is getting along with the updates... I hope that all our old stuff isn't lost. We've been here so long that I forget most stuff I have talked about...

Jason.
 
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Discussion Starter #7
How is the parking brake adjusted for rear drum cars? Is there already a thread up for that?...if so sorry
 
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If I can add a little here...

I adjust one side parking brake shoe at a time. What I mean is I remove both discs, and adjust one side. This way...there is no extra drag from the other brake shoe as you are trying to adjust each side equally. After adjusting the first side, I remove that brake disc and adjust the other side. Then install the other disc when you are done.

I have found that if I didn't do this 'one side at a time with the other disc removed' method...the first parking brake to be adjusted was done properly...and the second side to be adjusted would then be (falsly) loose. This looseness would be due to the drag of the parking brake shoe on the opposite side being transmitted throught the differential.

This not an issue with an open differential if the tranny is in Neutral. But, left in Park...or with a good working posi...both discs removed is the only accurate way I have found to adjust the parking brakes.

My 2 cents

Gary
 

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Not so long ago I upgraded my '93 Caprice with rear axle from '95 9c1. I also replaced rear cables to fit the parking brake. So now I have rear disc brakes and issues with parking brake adjustment.
I've read Parking Brake Adjustment Repost but still can't get it to work.
I used Adjusting Screws to set clearance between rotor and shoe and cables. And cables adjuster underneath the car.

After all these adjustments when parking brake is activated I can't not turn he wheel by hands. But it still doesn't hold the car, even on a small hill.
 

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Is the cable left/right equalizer in place and adjuster (ties the 2 rear cables together). Have you had a second person apply the park brake while watching what's happening under the car? The point is that aftermarket park brake cables for the disc brake system do not include the equalizer, which was included on the OEM version. Curious if you did address this, and how you did it.
 

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After installing rear axle I cleaned and lubed parking brake mechanisms so I know for sure that they are moving.
Then I installed new (Dorman) rear cables. The front one has the same part number for drums and discs so I didn't replace it. I also used the old equalizer, which I had with drum brakes setup to connect cables.

First of all I adjusted parking brake shoes. Then tightened up the cables using equalizer untill parking brake mechamism started to move. I was working alone so I could observe only driver side.
After that I pushed parking brake pedal 6 clicks as mentioned in manual.
It looks like driver side parking brake mechanism moves further than passenger side.

Could it be an issue with passenger side cable?
 

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Is any further adjustment possible at the equalier? I would check that first. Also, be sure the right-side brake cable is secured to the axle housing (use big tie-wraps) and that the right side cable is being held down by the cable guide, which is on the housing - right side only.
 

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Yes, at the moment there is plenty of room for adjustment at the equalizer. I tried to tight it, but it only results in parking brake pedal stiffness and also activating parking brake mechanisms.
I've done this procedure 3 times, checking every component, but each time I'm getting the same result: with applied parking brake I can't turn wheels by hands, but it won't hold the car on the hill.

I routed new right side cable the same way as old one was: metal braket near the right caliper, two tie-wraps on the axle and cable guide on the differential cover.

It seems like right cable doesn't pull the parking brake mechanism enough. To check it, I disconnected right cable from parking brake mechanism and measured the lenght before and after applying parking brake, it's only 6mm.
I also tried applying parking brake when only left or only right brake rotor is on the car. In case left is on I can feel the resistance on 5-6th clicks. In case right is on pedal resistance is not that substential.

P.S. I didn't replace parking brake shoes because there is plenty of material left. Inside rotor diameter is 190mm, which is ok. Shoes were set to ~189,5mm.
 
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