threeMBs

Pelican Parts has several tech articles on their site.

This is what the author recommends after the Motive bleeding:

"Now, get your family member to repeatedly press the brake pedal down at least five times, and then hold it down. Take care not to push the brake pedal all the way to the floor, as you can actually damage the master cylinder by driving the piston into an usually unused portion of the master cylinder and damaging the seals. Then open the bleeder valve on the right rear caliper. The system should lose pressure, and the pedal should sink to the floor.

When the fluid stops coming out of the bleeder valve, close the valve, and then tell your family member to let their foot off of the pedal. Do not let them take their foot off until you have completely closed the valve, or it will suck air back into the system. Repeat this entire procedure at least three times on each caliper in the same order as described previously.

I recommend that you use this procedure as a final step, even if you are vacuum bleeding or pressure bleeding. The high force associated with the pressure from the brake pedal can help free air and debris in the system."

threeMBs

Were you able to resolve the problem? If yes, wast just keep on bleeding (Motive pressure bleeder again or "manually" the "traditional" way with a helper?) over and over or was it something else that fixed it?

silvergl

To revisit an old thread. Is the purpose of the pressure bleeder to push fluid past the ABS pump? If I jumped the ABS relay, to fire the ABS pump would that push the fluid through? I have done this on other cars in the past, it is actually a really way to bleed brakes. Just hook up the wire to the relay, open the bleeder valve, cross the wires and wait until the pump pushes fluid out, close the valve and move on to the next wheel.

Or, is there another reason to use the pressure bleeder?

chassis

ABS actuation is not specified by MB, or BMW or Porsche.

Pressure bleeder is the prescribed procedure by MB.

Gbike

While changing brakes, check the movement of the ride height sensor arms - if it looks corroded or you can unscrew it and test the movement of it, do that. Mercedes has upgraded that part since the original - I would guess because the original ride height sensors in the early model years were prone to corrosion. I had the original one freeze up due to corrosion and snap in half on one of the arms - I thought it was an airbag failure as the car dropped in one corner (rear) - airbag was fine at 90k miles for me (I replaced it anyway).

The new hight height sensor is a different design than the one I replaced - more nylon bushings vs the original - it's a relatively inexpensive part used on many models - about 65 bucks each and they are rt/left side specific. I looked for cheaper prices online and they were same as the dealer at the time.

(when I called the dealer to see if in stock, they were like "oh, yeah, we always have those iin stock!" - haha - seemed like they were a very common replacement item!

AKSwift

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Hahahaha, looks like someone found it and dug it back up...

silvergl

Necessity is the mother of invention. I was unable to get a pressure brake bleeder, only vacuum. So a with a new Harbor Freight lawn sprayer and a plastic bard I was able to make it work. Basically exactly the same as Motive, but got it done last night. I bought 2 liter of liquimoly, only needed about one plus 500ml of some other fluid. In total I pulled out about 1.2L of fluid. all is clear now, seems to have done the job. I had to order a new PS cap to replace the one I put a hole in to attach to the sprayer.