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stock79 01-26-04 03:37 PM

Grinding noise/front brakes
 
After about 5 to 10 brake appliciations, I get a scraping noise from the front brakes and the pedal gets soft. I have a 79 and the condition is worse on a warm day. The pads are worn but still legal. I'm assuming heat is a factor, the longer I drive the worse it gets. I bled the brakes with speedbleeders so the fluid is clean and there does not appear to be any leaks. Isn't there some grease that goes on the caliper? I know 79 frt. brakes are poor, is there an easy upgrade. Thanks

black_sunshine 01-26-04 11:45 PM

Things to check are this:

Make sure the pads' backs and "ears" have SILICONE brake lube on them. Make sure your callipers' pistons aren't binding. Check the anti-squeak/knock tabs, and verify their condition/orientation (the solid tabs go on the top of the calliper, the springgy ones go on the bottom, relative to the orientation of the calliper when mounted). Check for fluid leaks. Check the vacuum hose(s) going to the brake booster, and verify the operation of the check valve. Check the master cylinder/proportioning valve. The pads should have no less than 4mm of material left on them. Verify that you used DOT3 brake fluid (or higher). You may want to rebuild the callipers since the rebuild kit is easy to install, and only costs a few dollars; the same applies to the master cylinder.

Speed bleeders are good, but it really helps if you've got a friend to operate the pedal, while you open and close the bleeder valve (the old fashioned way). Remember, sometimes air can leak in through the threads. To remedy this, I use a small ammount of teflon tape on the bleeder threads, making certain not not to have any excess get inside the calliper. Another method is to seal the threads, run a hose from the bleeder to a cup of brake fluid and pump it a few times. This doesn't always work, as air can get trapped within the bleeder hose. The fool-proof method is to use a vacuum pump (make sure those threads are sealed!). I think that any of the FB callipers/pads/rotors would fit on your car, but I can't verify this.

stock79 01-27-04 12:08 PM

Thank you for all the info!.First thing I am going to do is replace the pads and grease the backs and ears.


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