PeachParts Mercedes-Benz Forum - View Single Post - Brake Pedal Lacks Firmness. Not sure what next to do...

JamesDean · #13 10-30-2012, 08:06 AM

Update!

OK So my reverse bleeder kit arrived yesterday and I was excited to give it a try, even though it was raining like hell. I pulled in the garage and gave it a go.

I read the instruction and they said that it might take multiple methods of bleeding to get all the air out. In the past I've used the pressure bleeder and my shop recently did the 2-man pump method.

I started at the rear passenger wheel and injected 12 squeezes worth of fluid into the system. Then went around the normal pattern of bleeding, using 6-7 pumps each as the instruction indicated. I sucked out fluid as the reservoir filled up. The fluid that came back in the reservoir, was (no surprise) still very clean. I could still clearly see the bottom of my reservoir.

After that bleed, I gave it a quick drive. No really notable improvement. I could still feel air in the pedal. I cannot completely fault the tool as I was hurried to perform the work and probably didn't follow the instructions to a T. It was raining, I was tired and just wanted to get it done with.

So after I got some dinner my friend and I tried the 2-man bleeding on just the front brakes. After that I got a noticeable improvement in pedal pressure. I didn't have enough time to do the rear, but the difference of the combined reverse pressure bleed and 2-man bleed was good enough for the time being.

So, in summary, I think that the instructions were right, to get all the air out you need to do multiple bleeding techniques. I've been doing solely pressure bleeding for years on the car and it really didnt make a huge impact. So if I was someone struggling with this similar problem I would do the reverse-bleed and then the two man style bleed.

I'll post another update later in the week after the weather calms down and I can do a full 2-man style bleed.

I know some people on here will say: bah, the that contraption didn't do anything, it was the 2 man style that did it. However prior to using the reverse-bleed tool my shop did do the 2 man style bleed and it was not nearly as effective.