69 e-brake not engaging

[Michael L.]

Guys,

I'm trying to adjust the e-brake on my 69 after completing a total resto. I followed the instructions in the CSM but no matter how far I run up the adjusting nut I can't get the brakes to engage, even with the e-brake handle fully pulled up. Not sure if there is a secret to figuring this out or if I have to just pull the rotors and see what's going on. Thanks for any help.

Mike

[Owen L.]

Re: 69 e-brake not engaging

You may have done the following but I'll offer what I've done:
With the cable nut backed off so the cable has substantial slop, adjust the shoes' star wheels to the point of not allowing the wheels to rotate and then backing off X-clicks (don't remember the #). After that, adjust the pull-cable nut with the brake handle pulled up X-clicks (again, memory) to stop the wheels from rotating again. If all of this was done and you're out of nut adjustment, you need to ensure the cable is pulling on the shoe levers. If they move a noticeable amount, then the star wheels likely could use a few more tightening clicks. Test and repeat.

[Michael L.]

Re: 69 e-brake not engaging

I was able to get under the car today and I can't find where I would be able to adjust the star wheel. To be clear, this is a 69 so its rear disc and the e-brake set up is the one inside the rotor. There's no mention of a star wheel in my CSM instructions. Am I missing something?

Mike

[Leif A.]

Re: 69 e-brake not engaging

Michael,
Remove the rear wheels and you will see a hole (maybe two holes) on the face of the rotor hub...in between the studs. Rotate the hub until one of the two holes is at the six o'clock position, peek in the hole and you'll see the star adjustment wheel. See picture below

[Owen L.]

Re: 69 e-brake not engaging

I assumed when you mentioned a complete restoration you had done the work and replaced the shoes, springs, etc. The star wheels are inside the rotor's "drum" portion where the parking brake shoes are located. The setup and adjustment is basically the same for all '65 to '82 Corvettes with the '67-'82 being, for all practical purposes, identical as they share the same between-the-seats lever design.

Here's a YouTube link showing the process to adjust. I've only skimmed it but it looks like it is accurate. https://www.youtube.com/watch?v=SAsKA8noG7c I'll also dig out my chassis service manual to see what it says.

[Owen L.]

Re: 69 e-brake not engaging

Here is the adjustment procedure from my '72 CSM:
IMG_0598.jpg

The PB adjustment steps #4 & #5 are where you will see the star wheel through the hole and what's illustrated in the pic (fig 54).

I adjust my cable a little differently than measuring pull weight. Pull the lever handle 8-10 clicks and with the wheels mounted, tighten the adjusting nut so that the tires won't turn by hand. I've found that, for my cars, this engages the shoes so that they hold the weight of the cars adequately with the handle raised about 45-60 degrees.

[Michael L.]

Re: 69 e-brake not engaging

Thanks guys. Like with the typical drum brake setup, I was looking on the backing plate area for the adjustment hole. Owen, that additional info isn't in my CSM for '69. Only the cable adjustment portion is, as far as I can tell. Yes, the parking brake adjustments were supposed to have been totally rebuilt by the place that restored my trailing arms. I believe I used Ikerds but not sure. It's been probably ten years or more since I had them restored. (One of the problems with doing your own restoration in my experience. It takes forever to get it done and stuff you did at the beginning is long forgotten.) When they came back the rotors were already mounted so no way for me to assess the parking brake stuff but I think if I use this method I should be able to get it to work.

The other question I had was if you guys had a trick to adjusting the e-brake on a car with positraction. When I turn the wheel on either side they both turn making independent adjustments of the ebrake as per this technique difficult. Any tips?

Mike

[Joe L.]

Re: 69 e-brake not engaging

The other question I had was if you guys had a trick to adjusting the e-brake on a car with positraction. When I turn the wheel on either side they both turn making independent adjustments of the ebrake as per this technique difficult. Any tips?

Mike

Positraction has no bearing on the adjustment at the star wheels. You adjust one side as described above. Then, you go to the other side and, if necessary, rotate the rotor to align the hole with the star wheel. Then, you adjust that side. It's as simple as that.

[Michael L.]

Re: 69 e-brake not engaging

I guess because the adjustment is supposed to be until there is at least slight drag on the wheel with the handle set at two clicks (as per the 69 CSM) that there would be some impact on the adjustment on the second side to be done, but I'm probably overthinking it.

[Michael L.]

Re: 69 e-brake not engaging

After taking the wheels off and getting a look at the e-brake adjusting star I am unable to get it to move using the upward (towards the floor) adjusting motion that is used in the youtube video on either side. Of note, my adjuster is completely collapsed, with zero threads showing. After struggling with this for a while, I realized that my star adjuster on the passenger side appears to be on opposite side of the spacer that connects the bottom of the shoes when compared to the youtube video. His adjuster appears closer to the rear shoe, but mine is closer to the front shoe. on the Drivers side it is closer to the rear, but I can't get that one to open with the upward toward the floor motion either. Is it possible that the guy who assembled these when they were restored put the star adjuster on the wrong side? For drum brakes, with a self adjustable feature, this would be difficult to do but after looking at the e-brake setup in the CSM there does not appear to be anything that would prevent putting the star adjuster on either side. My question is if this star adjuster is on the other side than it should be, that would mean I would have to go downward with the star, towards the ground, to open the e-brake shoes, correct? Rather than just wack on this thing until I got it to move I would like to know if possible what direction I'm supposed to be moving this thing first off. And BTW the lack of movement is not related to wear or gunk on the adjuster as the parts inside are pristine and the e-brake has not been used since the car has been back together. Appreciate anyone who can set me straight on this.

Mike

[Owen L.]

Re: 69 e-brake not engaging

I don't recall from the last time I worked on my parking brake shoes, so this info is from the same '72 CSM above: The star wheel should be closer to the rear shoe on the left (driver's) side; closer to the front shoe on the right (passenger).

It sounds like your star wheels are installed in reverse orientation – and their adjustments are full retracted, so it's no surprise you are getting no parking brake activation with the lever-cable adjustment.

Are your rotors riveted on? If not, you may want to consider fixing the reversed adjuster. No matter what, you may just have to really exert some pressure on the levering tool to get the star to rotate. They can be pretty stiff and difficult to move, especially if a little (or a lot of) surface corrosion has started on the wheel.

If the adjusters are in reverse locations, yes, I'd assume you'll need to lever in the opposite directions than the instructions indicate.

[Owen L.]

Re: 69 e-brake not engaging

I'm surprised your CSM doesn't have practically identical information to my '72 manual - these publications weren't revised significantly from year to year for these types of service procedures. Does your manual look like this?
Screenshot 2022-12-01 at 7.54.20 PM.jpg

Look in section 5 around pages 35-45. The '72 manual has a specific section for the Corvette disk brake services.

[Michael L.]

Re: 69 e-brake not engaging

Thanks Owen. I'm assuming that the thread on the star wheel and the stud it screws to are standard i.e. non-reversed thread? If that's the case then yes I will definitely have to rotate the star in the opposite direction than what the video shows. If that's the case I don't think I'll have much difficulty getting it adjusted so long as I'm moving it in the correct direction.

Yes my rotors are riveted so pulling them would be very difficult.

Mike