e brakes

[sam84svo]

I have put new pads and caliper on the back brakes and adjusted e brake cable were it is tight put my e brake is not holding the car. e brake was working before i change the pads and caliper. What do i need to do to get e brake working to hold my svo on a hill.

[kiwi]

Watching this....I THINK there is an adjustment inside the caliper.....

[SVOeric]

I'm a little confused. When you pull the e-brake handle, it's tight, but it don't hold the car ? is that the problem ?

[svono50]

Yep, the caliper piston needs to be adjusted. The piston is basically a two-piece threaded unit that you need to set when replacing pads. It will self-adjust a bit, but if you thread the piston in too far, it would take forever for it to adjust back out. I know there is a recommended pad gap when installing new pads, but I think I just set mine to just be able to slide the pads onto the rotor and it seemed to work well. I could dig back through my pics at home to see if I snapped any details on my install a few years ago if you need it. Good luck.

[kiwi]

I need that info Ted.

[SVOeric]

A quick search produced .020 - .025 as the recommended gap

[RFranklin]

Yes, getting the rear brakes adjusted correctly is a pill. I used the gap Eric noted and still did some trial and error getting right. I actually had to replace a rotor when I had it to close and it wasn't backed off during release. It didn't feel that bad at first, then came the smell and smoke.

[sam84svo]

thanks for help. I well try gaping them right. I did not know I needed to gap them.

[svono50]

Yep, you have to adjust like on drum brakes, but you have to pull the caliper off to adjust with these. Here is the text from the service manual on this, it assumes you adjusted the caliper's piston in enough to get the new pads over the rotor to begin with:

Piston Position Adjustment: Pull the caliper outboard until the inner shoe and lining is firmly seated against the rotor and measure the clearance between the outer shoe and caliper. The clearance must be .794 to 2.381mm (1/32 to 3/32"). If it is not, remove the caliper, then readjust the piston to obtain the required gap. Follow the procedure in Step 2 and rotate the shaft counterclockwise to narrow gap and clockwise to widen gap (one quarter turn of the piston moves it approximately 1.588mm (1/16").

CAUTION: A clearance greater than 2.381mm (3/32") may allow the adjuster to be pulled out of the piston when the service brake is applied. This will cause the parking brake mechanism to fail to adjust. It is then necessary to replace the piston/adjuster assembly following the procedures under Overhaul.

[Nito2v]

Is there a special tool that we can purchase that allows us to turn the piston?

[RFranklin]

Disk Brake Tool Options

You can go a couple of ways. The first one is the Universal Cube that works fairly well. They sell for $5.00 or so. The option is to buy a Disk Brake Service Kit that has a better selection of sizes and work better. They can go for $39.00 and up. If your not a high production shop you can get either at Harbor Freight and for the money they work just fine. Of course these are also available at other suppliers. Here are a couple of pictures for reference.

Disk Brake Cube.jpg Disk Brake Service Kit 2.jpg Disk Brake Service Kit.jpg

[SVOeric]

FYI, the square block will cause nothing but cursing... you really need the tool in the case.

[gbeaird]

FYI, the square block will cause nothing but cursing... you really need the tool in the case.

+1 on that!

[GAboySVO]

Also, the Haynes manual says that you have to loosen the backing nut 1/2 turn before you screw the piston back in. If you didn't do this, the parts inside probably are no longer functioning correctly. I just went through this on the road warrior.

[Nito2v]

Okay, so I will pick up a tool kit. I have been having trouble with the brakes since early spring. I didn't know that you had to gap them so I just pumped the brakes until the piston was close enough to the rotor to hold it still. Could be further out though.

On one occassion I was able to get the E-brake to finally hold the car on a hill. The next day the e-brake wouldn't hold the car again. Not sure what that was about.

The e-brake cable on the pass. side is stretched (doesn't move the lever/arm on the caliper). Also the arm on the pass. side caliper seems to be in a different position than on the driver's side. Slightly further towards the back when disengaged.