brake pads/caliper--need help! - PeachParts Mercedes-Benz Forum

JamesDean · #1 11-24-2005, 02:39 AM

hey ,

I am doing my front brakes...
I am having trouble with this outter piston..it seems to be stuck in the position as if i were braking..i have tried a crowbar--all that seems to do is wiggle my rotor a little bit. I have the reservoir cap off. I managed toget the back pad in after having to muck with that stupid heat shield. I tried to take off the caliper but i cannot get to the second bolt with anything its behind that tie rod...any words of wisdom?

Thanks
Kris

#2 11-24-2005, 03:17 AM

Been helping him for awhile now:

Update:

Wrong two bolts...got the right two identified.

Piston stuck (I think) becuase it is so far out that it is cockeyed going back in and needs to be seated properly.

Brakes at 3 in the morning...fun!

JamesDean · #3 11-24-2005, 04:16 AM

ive called it a night at 4am...i cant seem to budge these caliper mount bolts...i will retry in the morning...get that thing off thats goign to be a REAL pain!...clean the pistons etc and pray to god it all comes out nice

then onto the other side wheel...and pray to all the dieties in the heavens that its straight forward and easy no trouble

Ara T. · #4 11-24-2005, 04:40 AM

This happened to me once, the piston just got really really stuck, I just kept using my screwdriver and all the strength I had to get it back in. But yours sounds worse if you couldnt even get it out using the leverage of a crowbar.

MS Fowler · #5 11-24-2005, 06:54 AM

After you remove the caliper, you can try to push the piston back in using a large C clamp, or even a vise, if you have one that will fit the spaces involved.
You can also go the other way. There is a tool that grips the inner diameter of the piston. The tool can then be tightened to provide more grip, and then with a twisting motion, the piston can be removed. You will probably find rust pits all around the piston. For a shorterm fix, you can polish/buff the piston and reinstall with a new seal. The better solution, once calipers become stuck, is to replace the caliper with a rebuilt one.

JamesDean · #6 11-24-2005, 12:00 PM

i cant even budge these caliper mount bolts...they are in there pretty good...im going to find a 19mm in 1/2 drive and see what that gets me

tjohn · #7 11-24-2005, 12:35 PM

A little wd-40 or pbblast will go a long way. Also, have you slapped a cheater bar onto the ratchet? A little mechanical advantage makes all the difference in the world.

JamesDean · #8 11-24-2005, 01:16 PM

ive been hosing em down with WD-40...i dont have anytthing i can use as a cheater bar

I am now using a 1/2" drive with a deep socket 19mm

WANT '71 280SEL · #9 11-24-2005, 01:43 PM

Use a cheater bar. The caliper needs to be replaced with a rebuilt one. Autozone sells them pretty cheap. They're rebuilt MB ones BTW. They're around $25 + $20 core charge. You'll have to order them over the internet. Don't forget to buy brake hoses for them as well from Fastlane.

Thanks
David

RAYMOND485 · #10 11-24-2005, 01:54 PM

1984 300d Turbo 135k
Go To Auto Zone For 1/2 2 Ft Cheater Bar Best Tool To Work On
Brakes Or Use Small Pipe To Slip Over Tool Tap The Tool To Seat
19 Mm Socket

Brian Carlton · #11 11-24-2005, 02:03 PM

Quote:

Originally Posted by JamesDean

ive been hosing em down with WD-40...i dont have anytthing i can use as a cheater bar

I am now using a 1/2" drive with a deep socket 19mm

You can't break them loose with a 1/2" socket wrench and a 19mm socket.

It's marginal with an 18" breaker bar. It'll take almost everything you have.

#12 11-24-2005, 02:08 PM

Quote:

Originally Posted by Brian Carlton

You can't break them loose with a 1/2" socket wrench and a 19mm socket.

It's marginal with an 18" breaker bar. It'll take almost everything you have.

Especially if the previous people used locktite like they were supposed to.

I've found the breaker bar I have gives me enough to break them loose. They go "pop-wham" and then are loose...and I have a new porthole in my knuckle

Just get in a good position...and give it some force.

Or use a 1/2 drive pnumatic impact

Brian Carlton · #13 11-24-2005, 05:18 PM

Quote:

Originally Posted by Brandon314159

Especially if the previous people used locktite like they were supposed to.

Every time I have put them back on, I've never used Loctite. I cannot imagine these bolts having any possibility of coming loose if they are torqued to 90 ft.-lb. I believe the spec is 80 ft.-lb. and another 10 just makes it that much more impossible for them to back out.

I never want to tear the head off due to Loctite seizing the threads.

JamesDean · #14 11-24-2005, 05:29 PM

I am trying some Liquid Wrench to see if that helps. I'll let that sit for a while then im going to toss on the 19mm deep well and the 1/2" drive and go at it...maybe my next investment should be an aircompressor and some tools...hmmm

kris

#15 11-24-2005, 05:37 PM

Quote:

Originally Posted by Brian Carlton

I never want to tear the head off due to Loctite seizing the threads.

Locktite doesn't sease the threads (atleast to the degree rust would)...it actaully provides a medium between the metals.

On boats this is often used between dissimilar metals (aluminium/stainless) to prevent corrosion.

My 300SD had blue locktite on all of its bolts...

I wouldn't worry about them coming off if properly torqued but I WOULD worry about corrosion

Just a thought