mikefamig

I've been reading about flushing the ABC system and decided to open one of the strut bleeders to see how that goes. I've had trouble with brake bleeders being stuck in the past and wanted to see how difficult it would be to open.

On my 2005 R230 the bleeders are fairly easy to get to but the first one that I tried to open was very tight. I had to put a 13mm wrench on the bleeder body and an 11mm on the bleeder valve and it was very difficult to turn. When I did manage to turn the bleeder open the strut drained very quickly after only cracking the valve a very little bit open. Then it was again very difficult to turn closed.

Is this normal? It is as if the threads are a press fit. The valve never did crack open loose but only budged a very little bit. This makes me hesitant to touch the other three bleeders for fear of damaging one.

Mike.

kbob999

Do you live in a salty or humid area? Maybe they are rusted in place?

If this were my experience, I would use a penetrating oil and maybe apply 500 degrees of heat before cracking the others.
Once the fluid is out, you could remove the bleed nipple completely to see if the the threads are messed up. Normal precautions for getting dirt in the system applies.
I did this on my car and had no issues with cracking open and bleeding each corner. Was no different than bleeding brakes.

mikefamig

"I did this on my car and had no issues with cracking open and bleeding each corner. Was no different than bleeding brakes."

Thanks, that is what I wanted to hear. The car has always been garaged and only has 26k miles. The bottom of the car is almost as clean as the top. I will try one more bleeder and see how it behaves.

I don't consider it absolutely necessary to open the bleeders in order to flush the system and I'd rather just not open them if it is going to end up being painful. Most accounts that I've read online just bleed from the return line and I found one Mercedes document that says to not flush at all. They just recommend replacing the filter with a new 3 micron filter. I think that the original was 10 micron?

The first bleeder that I opened was so hard to turn that I was happy just to get it to close and stay dry again.

Mike.

mikefamig

I'd rather leave the bleeders undisturbed than deal with repairing them at this point. If I ever need to replace a strut or do another repair that necessitates bleeding I'll deal with it then.

Mike.

Agent-A01

It is not necessary to bleed the system.

Once you replace anything in the system, you can just do STAR rodeo test OR play with the raise function for a bit and drive it.
Air will go to the reservoir on it's own over time.

kbob999

The bleeding is to remove the mainly dormant fluid stuck at the ‘dead end’ at the strut. It is not circulated with the rest of the fluid.
It was clearly darker than the rest of my ABC fluid after driving 1000 miles.

mikefamig

Thanks, good to know.