Tight brake caliper - BMW Forum

6670charger · 04-11-2011, 10:52 AM

My left front brake caliper is sticking/tight. It won't let the wheel spin freely.

Does this mean the caliper is shot, or is there a way to adjust it?

Thanks.

jimmythepie · 04-12-2011, 01:21 PM

this is a common problem with BMW, had it myself on my three series. I eventually changed the caliper as I felt having it reconditioned wasn't worth the effort. Once they start doing this it only tends to get worse so bite the bullet now and it sorted. By that I mean if you managed to free it it's going to happen again.

Best of luck with it and happy driving

6670charger · 04-12-2011, 02:49 PM

OK. That's the impression I got from another site. Think I'll try to get this one working for the short term so it'll pass inspection, and get a new caliper to replace it.

Thanks.

tyan_nt · 04-30-2011, 08:27 PM

Curious how you made out freeing up your caliper?

6670charger · 05-01-2011, 01:57 AM

Well, I've worked on it a bunch, but, so far, no change.

I removed the old calliper and replaced it with a used one I had handy. The piston compressed just fine during installation; didn't have to force or anything like that. Bled the brake line properly too. Ended up tighter than before.

Finally, we traced the line up to the ABS control module and bled there. A bunch of black crap came out of it in the fluid. It did release some pressure though, but, now I'm right back where I started from.

I have a feeling the problem may lay in the ABS module and I may have to take it to BMW to have them confirm or deny that, unless someone has a better idea.

brettski · 05-01-2011, 08:11 AM

Try taking it to a specialist brake shop. This is their world and they will probably be cheaper than going direct to BMW. It may be that the ABS unit has some other form of fault that hasn't presented itself as yet. But you probably don't want to find out the hardway that its not functioning as it should.

Jack Dabsy · 05-01-2011, 08:22 AM

I would totally renew the brake fluid too... If there is crap in one line then the others may have too and it can work back thru the system !!!

6670charger · 05-01-2011, 09:13 AM

Quote:

Originally Posted by brettski

Try taking it to a specialist brake shop. This is their world and they will probably be cheaper than going direct to BMW. It may be that the ABS unit has some other form of fault that hasn't presented itself as yet. But you probably don't want to find out the hardway that its not functioning as it should.

Good idea. Hadn't thought of that. I'll have to ask some of my friends if there is one around here.

Thanks.

brettski · 05-02-2011, 05:06 AM

If the brake fluid hasn't been changed recently, start with a total flush with new fluids. Make sure you get as much of the old fluid out of the master cylinder system before you add any new fluid (in other words do it properly). Bleed the fresh fluid through each line and hopefully this will flush any contamination out of the ABS unit.

justin1180 · 05-02-2011, 12:50 PM

you also need to make sure that you check the rubber portion of the brake hose that goes to the caliper. sometimes they will collapse inside. they will allow you to apply brakes but when you release the brakes, the hose will collapse inside and not allow the brake fluid to return up the lines. hence your brake not releasing. if you have the hose disconnected, disconnect it further up the line where it attaches to the hard line and try to spray fluid in the opposite direction and see if fluid comes out.

Jack Dabsy · 05-02-2011, 12:58 PM

I agree, Justin. If a hose fails internally, it will "ACT" as a non-return valve causing the pressure to remain at the caliper! This cannot be inspected visually but if the hose looks recent then I would eliminate that idea until the last resort !

6670charger · 05-02-2011, 02:43 PM

Good suggestions guys. Thanks.

I have to do a little fuel line replacement this weekend anyway, so while I'm in the shop and have it on the hoist, I'll have someone watch/feel the line while I test the brakes. I'll also flush the lines with new fluid.

6670charger · 05-07-2011, 02:10 PM

Good news!! Took it to the shop today and put her on a lift. Bled and flushed the brake lines and put in all new fluid. The old stuff was really dirty. Nearly black when I dumped it in the recycled tank. After flushing and replacing the dirty fluid, and cleaning out the filter, my left front wheel now spins as freely as the right front.

Thanks for all your suggestions. They really helped. It was also a pretty cheap fix.