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Hoping someone can lend some insight.

I replaced the pads on my 330ci today; I've done this on other cars but this was the first time on my 330. I was extending one of the front pistons to apply lubricant after cleaning the caliper, and I went too far. The piston came loose and a small amount of brake fluid spilled out of the caliper. After cleaning and re-greasing, I was able to get the piston back in its guide, and retracted it fully. I have watched for several hours now and see no sign of leaking brake fluid, and the brake fluid reservoir is exactly where it should be. Am I OK?

Also, I've got some suggestions for the brake pad change FAQ:

1. Check to see if your new pads have a metal anti-squeal shim, similar to the stock pads. If not, your best bet for preventing squeal is to order and install these shims. (For my car, it's NAPA part # BA0842017.)

2. If you're still having squeal problems, apply anti-squeal compound to the backs of the pads in the places the pads contact the piston or caliper. Be sure to give the compund time to set up (I recommend an hour or more), and after reassembling the caliper, give it some more time to dry before braking.

3. Clean the entire caliper and regrease the piston, getting under the dust boot with the grease. Sticking calipers can cause nasty problems.

Thanks for replies.
 

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cakennedy said:
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I was extending one of the front pistons to apply lubricant after cleaning the caliper, and I went too far. The piston came loose and a small amount of brake fluid spilled out of the caliper. After cleaning and re-greasing, I was able to get the piston back in its guide, and retracted it fully. I have watched for several hours now and see no sign of leaking brake fluid, and the brake fluid reservoir is exactly where it should be. Am I OK?
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What exactly were you lubricating while extending the piston? I hope it wasn't part of the piston that rides inside the caliper bore and is covered with brake fluid. Petroleum based lubricants will do horrible things to the brake system if they make it into the fluid side of the sysem.

If you were careful about not damaging the piston seal and dust boot when you inserted the piston back into the caliper, chances are the car is fine. You definitely got air into the system and will need to bleed the brakes or else you will probably suffer from a soft brake pedal. Since the brake system operates as high as 1500psi, you won't be able to tell if anything is damaged by just letting the car sit. Start the motor and push hard on the brake pedal a dozen times. Check for leaking fluid and check the reservoir level. If everything checks out, go for a short drive folowed by a fluid level and leak check. Check again in a couple days just to be sure.


Ed
 

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If you spilled brake fluid from the piston you need to bleed that brake. You undoubtably have a bubble there that will make that particular brake spongy. Second, There is no need to put anti-squeal on the inboard pads.. It's only needed on the outboards that are in a fixed position and rely on riding a single point. Bleeding the brakes will be a simple process though. Good Luck!
 
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