DIY - Bleeding Brakes
!!! A WARNING UP FRONT !!! - Brake fluid reacts very badly with paint!!! Guaranteed you will ruin any paint the brake fluid touches!!! Be very careful when you are moving any fluid containers over paint (i.e. you might want to bring the fluid to/from the engine compartment from the front of the car instead of over a fender, just in case ...).
I bought a 'power bleeder' for this job (and my other cars), and find it makes bleeding a lot easier - you put the new brake fluid in the power bleeder and pump it up. Then it's just a matter of bleeding at each corner and keeping an eye on the fluid in the reservior. Ideally, when you're finished bleeding all 4 wheels, there won't be any more fluid in the power bleeder and the level in the reservior will be at max or below.
The basic idea is to bleed the longest lines first, so the order to do this is passenger rear, driver's rear, passenger front, driver's front. With the power bleeder, the most time consuming part is jacking up each corner and taking off/putting on the wheels (you might be able to do without, but I wanted to check the brakes - doing the 60K mile maintenance).
Tools/materials:
- clear bottle(s) for draining old brake fluid into
- small hose (1/4"??) for draining fluid from bleeder nipple into bottle
- 9mm wrench for openning/closing bleeder nipples
- 1 liter of DOT 4 brake fluid
- Power Bleeder (I got a Motive, but there are other brands)
The basic procedure is:
1) Take off the cover over the brake fluid resevior (turn the 2 fasteners near the windshield 90 degrees, the front attachment point just slides out).
2) Unscrew the cap from the brake fluid reservior and screw on the cap from the power bleeder.
3) Put ~3/4 liter of DOT 4 brake fluid into the power bleeder, put cap on power bleeder, and pump up to ~10 psi.
4) Jack up passenger rear of car, take off tire, attach hose to bleeder nipple, put other end of hose in bottle, and then crack open bleeder valve just a bit (1/4 to 1/2 turn should be plenty - if you open it too much, fluid will seep past the threads on the nipple). If you're using a clear bottle and have the hose drain the fluid down the side of the bottle, I found that the dirty fluid will stay on the bottom and the new/clean fluid will stay on the top ... so when I got a nice layer of clear fluid on the top I knew I was done with that corner. Tighten the bleeder nipple (not too tight - don't strip it), put the wheel back on, and move on to the next wheel.
5) Repeat #4 for other 3 corners of car HOWEVER you need to keep an eye on the fluid in the reservior, the fluid in the power bleeder, and you need to keep the bleeder pumped up to ~10 psi. Add more fluid if necessary, but you don't want to have too much fluid in there or you'll have to bleed the extra out in the end.
6) When you're on the front wheels, you want to try to guesstimate on the fluid so that there will be none left in the bleeder and the fluid will be below the Max line in the reservior.
7) When all 4 corners (wheels) are done, and you've made certain the brake fluid level is below the max line, relieve pressure by unscrewing the top of the power bleeder, remove the bleeder cap from the reservior, top off if necessary, put the cap on the reservior, put the cover over the reservior back on, and you're done!!!
The first pics are: The Power Bleeder itself, the whole power bleeding setup, and the cap on the reservior.
Last edited by mtnman82; Oct 19, 2008 at 03:46 PM.
In the picture of bleeding the rear brake, you can kind of see how the fluid is darker at the bottom of the bottle than at the top. I have the bottle leaning a bit (careful not to spill ...) so the fluid slides down the side of the bottle to avoid stirring. When I saw it coming out clean, I knew I was good.
Note that 1 liter is about the perfect amout of brake fluid for a flush. I had just a tad left in the can when finished. Cheers!!!
Last edited by mtnman82; Oct 19, 2008 at 03:41 PM.
I need a worst case scenario - can just the bleeder valves be replaced, or will the whole caliper need replacing?
ALWAYS WEAR SAFETY GLASSES when working with this stuff
It is not hard to get a random splash of this in your eyes
Trending Topics

The Best of Mercedes & AMG
My manual says DOT4
https://mbworld.org/forums/e-class-w...uid-flush.html
Seems like a nice deal (after DIY I guess
). Was lurking on the E-class forums and saw this.

I would advise good glycol fluids blended specifically for new ABS and ESP systems.
https://mbworld.org/forums/e-class-w...uid-flush.html
Seems like a nice deal (after DIY I guess
). Was lurking on the E-class forums and saw this.
Score.







