Mercedes-Benz Forum banner

1 - 4 of 4 Posts

·
Registered
2005 E55
Joined
·
785 Posts
Discussion Starter #1
Hey guys,

This issue is happening with my W211 E55 but there seems to be a lot of power steering experts on the W163 forum and I followed the procedures on this forum to do the exact procedure on my ML350 with great results. From what I understand, power steering systems are quite similar on all M112/113 cars.

So here is the issue. Power steering fluid leak from the reservoir seal. Replaced seal, reservoir from dealer and correct fluid. Bled the car with wheels up, engine off. Started car, bled the system and everything seemed good.

Next cold start, I hear the pump groan and fluid foam and leak out of the reservoir cap. Bleed with engine off again (50 times lock to lock, wheels up) but as soon as the engine is started the pump sucks in the fluid in the reservoir and the fluid starts to foam.Turn off engine and more fluid foams out of the cap.

The strange thing I noticed is the fluid being sucked into the pump quickly when engine is started, seems like the return line can't keep up (?)

If I manually add fluid into the reservoir while the fluid is being sucked into the pump while the engine is running, the pump will stop groaning and the fluid won't foam. There is still turbulence and small bubbles in the reservoir. But on the next cold start, the fluid foams out of the reservoir almost instantly.

I'm kind of stumped, I ordered another genuine reservoir from the dealer in case a big air bubble blew the filter in the first one. I'm going to bleed it correctly again and if it keeps happening I'm guessing it's time to replace the pump. There are no leaks from the rack or any other lines, but there is a sloshing sort of noise coming from the rack area while the wheel is turned from lock to lock...could it be big air bubble stuck in the rack?

Thanks in advance
 

·
Premium Member
2000 ML55 sold? 2013 ML500,? 2015 C250 estate wagon, 1927 Dodge 4 sedan, 1929 Dodge
Joined
·
4,914 Posts
Sounds like it has a broken strainer or never had one. If you did the L/L 50 times you would imagine the air would be all gone. See how it goes with the new reservoir.


Sent from my iPhone using Tapatalk
 

·
Registered
2005 E55
Joined
·
785 Posts
Discussion Starter #4
UPDATE.

Took the old pump and it had about half a inch of play in the shaft. Put in a new pump with the new reservoir and the PS system is fixed!
 
1 - 4 of 4 Posts
Top