Nova sticking front brakes

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Sun 28 Jan 2007 08:25
Nova sticking front brakes - local yokel
89 Nova - OS front wheel got very hot on a five mile journey. Jacked up the front, and the OS wheel is very sticky to rotate compared to the NS.

Clearly the caliper/piston is failing to return - is this a simple case of stripping out the pads and working the piston a few times, or is the slave assembly suspect, and in need of replacement? Car is for sale....
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Sun 28 Jan 2007 10:11
Nova sticking front brakes - piston power
crack off the bleed nipple and push back the cylinder if it will go back! then pump the brakes and repeat, you can also rotate the piston but some times it nips the seal's and they weep fluid, just peel back the rubber seal and squirt wd40 into the cylinder this will make things easier.. or replace the whole damn thing!! good luck
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Sun 28 Jan 2007 12:06
Nova sticking front brakes - Number_Cruncher
There are three (likely - many more not so likely) possibilities, which are; the main caliper piston is sticking, the pads are sticking in the caliper, or the caliper slides are sticking.

Releasing the brake bleed nipple is good advice, because Nova master cylinders are prone to their seals "turning" if you push the fluid back too quickly.

When removing the pads, the pins knock out much easier from the inside of the caliper - the holes for the pins on the inner edge of the caliper are smaler than the outer ones.

Whatever you do, don't be tempted to put copperslip on the caliper slides. These slides have a square section rubber ring, which is intended to pull the single piston caliper back off when you release the brakes. This rubber swells up and sticks if copperslip is used. The only cure if copperslip has been used is a new slide assembly.

If you find the main piston is siezed, then, the best repair is a replacement caliper. Be sure to obtain the correct grease for the slides. In the absence of the correct GM grease, I have found red rubber grease as specified for brake system seal lubrication to be OK.

Number_Cruncher
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Sun 28 Jan 2007 15:41
Nova sticking front brakes - local yokel
Cheers chaps - after a couple of attempts I got quite quick at the cycle of jack, support, wheel off and pads out to lever the piston back in. Seems to be behaving itself.

LY
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