Hard steering wheel
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Hard steering wheel
Hello,
Bought a 2008 ML320 CDI last week, all was fine at first though i thought the steering had some rough spots here and there while turning. Checked fluids all is good. Now i start the vehicule the steering turn from left to right without any hesitation , i Drive for maybe 30 seconds and then i have to put all of my strenght into turning that wheel. Apparently the pump was replaced prior to me buying the car, i wonder if the oil could be the problem.
There is no weird noise coming from the pump and i have taking a look at the steering joints and all seems ok.
What could it be?
Thank you for your input
Bought a 2008 ML320 CDI last week, all was fine at first though i thought the steering had some rough spots here and there while turning. Checked fluids all is good. Now i start the vehicule the steering turn from left to right without any hesitation , i Drive for maybe 30 seconds and then i have to put all of my strenght into turning that wheel. Apparently the pump was replaced prior to me buying the car, i wonder if the oil could be the problem.
There is no weird noise coming from the pump and i have taking a look at the steering joints and all seems ok.
What could it be?
Thank you for your input
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Do you know if the P/S reservoir was changed along with the pump?
You said apparently. Did the previous owner tell you that it was changed?
You said apparently. Did the previous owner tell you that it was changed?
Last edited by Maj. Dundee; Oct 26, 2019 at 04:22 PM.
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Thanks
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Whenever the P/S system is opened, e.g. replace part, the eng is not to be started until the bleeding process is conducted.
In all probability, the problem was with the reservoir which has a screen inside it that dampers noise. If that screen ruptures you will have the problem that you now have.
I suggest that you raise both front wheels off the ground, turn the key to pos. #3 (do not start the eng). Remove the reservoir cap and you or someone else must turn the steering wheel all the way to one side and then to the other repeatedly while you looking into the reservoir, do not see any bubbles. Turning the steering wheel might take up to 20-30 times before the bubbles disappear.
Take it for a test drive and if the problem still exists, you must replace the reservoir and conduct the same procedure again.
Buy the reservoir and from a dealer only.
In all probability, the problem was with the reservoir which has a screen inside it that dampers noise. If that screen ruptures you will have the problem that you now have.
I suggest that you raise both front wheels off the ground, turn the key to pos. #3 (do not start the eng). Remove the reservoir cap and you or someone else must turn the steering wheel all the way to one side and then to the other repeatedly while you looking into the reservoir, do not see any bubbles. Turning the steering wheel might take up to 20-30 times before the bubbles disappear.
Take it for a test drive and if the problem still exists, you must replace the reservoir and conduct the same procedure again.
Buy the reservoir and from a dealer only.
Last edited by Maj. Dundee; Oct 31, 2019 at 05:51 AM.
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Whenever the P/S system is opened, e.g. replace part, the eng is not to be started until the bleeding process is conducted.
In all probability, the problem was with the reservoir which has a screen inside it that dampers noise. If that screen ruptures you will have the problem that you now have.
I suggest that you raise both front wheels off the ground, turn the key to pos. #3 (do not start the eng). Remove the reservoir cap and you or someone else must turn the steering wheel all the way to one side and then to the other repeatedly while you looking into the reservoir, do not see any bubbles. Turning the steering wheel might take up to 20-30 times before the bubbles disappear.
Take it for a test drive and if the problem still exists, you must replace the reservoir and conduct the same procedure again.
Buy the reservoir and O-ring from a dealer only.
In all probability, the problem was with the reservoir which has a screen inside it that dampers noise. If that screen ruptures you will have the problem that you now have.
I suggest that you raise both front wheels off the ground, turn the key to pos. #3 (do not start the eng). Remove the reservoir cap and you or someone else must turn the steering wheel all the way to one side and then to the other repeatedly while you looking into the reservoir, do not see any bubbles. Turning the steering wheel might take up to 20-30 times before the bubbles disappear.
Take it for a test drive and if the problem still exists, you must replace the reservoir and conduct the same procedure again.
Buy the reservoir and O-ring from a dealer only.
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Whenever the P/S system is opened, e.g. replace part, the eng is not to be started until the bleeding process is conducted.
In all probability, the problem was with the reservoir which has a screen inside it that dampers noise. If that screen ruptures you will have the problem that you now have.
I suggest that you raise both front wheels off the ground, turn the key to pos. #3 (do not start the eng). Remove the reservoir cap and you or someone else must turn the steering wheel all the way to one side and then to the other repeatedly while you looking into the reservoir, do not see any bubbles. Turning the steering wheel might take up to 20-30 times before the bubbles disappear.
Take it for a test drive and if the problem still exists, you must replace the reservoir and conduct the same procedure again.
Buy the reservoir and O-ring from a dealer only.
In all probability, the problem was with the reservoir which has a screen inside it that dampers noise. If that screen ruptures you will have the problem that you now have.
I suggest that you raise both front wheels off the ground, turn the key to pos. #3 (do not start the eng). Remove the reservoir cap and you or someone else must turn the steering wheel all the way to one side and then to the other repeatedly while you looking into the reservoir, do not see any bubbles. Turning the steering wheel might take up to 20-30 times before the bubbles disappear.
Take it for a test drive and if the problem still exists, you must replace the reservoir and conduct the same procedure again.
Buy the reservoir and O-ring from a dealer only.
So i did all that is writen here, the oil rushes out of the reservoir when i turn the steering wheel. i saw some bubbles but also waves of oil gushing out the reservoir, is that normal? I took the reservoir out, apparently the hose to the pump wasn't tight enough cause i didn't loosen it to get it out. Cleaned the reservoir to make sure it wasn't clogged or anything reinstalled and tightened everything, same thing happens, oil is getting out without any bubbles. Should i replace the reservoir has said? Or investigate further?.
Thanks again
Trending Topics
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
There should be no gushing if the eng. was not running. If not that is a sign of air entering the system.
Did you withdraw some fluid so the level is 10mm below the level, #2 in PDF?
Did you tighten the hose clamp?
Did you withdraw some fluid so the level is 10mm below the level, #2 in PDF?
Did you tighten the hose clamp?
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
I ordered a vacuum pump to make sure system is sealed, will have some more development tomorrow.
I took a video of the oil coming out but dont know how to share it if you'd like to see.
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Hello,
So, today i used the vacuum pump to bleed the system, incredible work! Super easy to use and took all the air out of the system. Took the car for a spin , after 2 minutes same thing happened has before, the steering is hard to turn. For sure There is no leak in the system, the pressure held for 5 minutes without moving.
Do you still think that it is caused by the reservoir? Is There any way to check the pump? Could it be the oil?
Thank you
So, today i used the vacuum pump to bleed the system, incredible work! Super easy to use and took all the air out of the system. Took the car for a spin , after 2 minutes same thing happened has before, the steering is hard to turn. For sure There is no leak in the system, the pressure held for 5 minutes without moving.
Do you still think that it is caused by the reservoir? Is There any way to check the pump? Could it be the oil?
Thank you
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
I have already told you that the reservoir must be replaced. Whenever there is a steering problem, everyone believes that it is the pump.
And if you decide to change the reservoir, do not start the eng. until you bleed the system.
And if you decide to change the reservoir, do not start the eng. until you bleed the system.
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Reservoir on its way. Do you have a flush procedure?
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Wow, that brownish metal is not a good sign. Is there anything unusual with the color of the coolant? Check the color because the radiator cools the P/S fluid and it could be leaking into the radiator.
Thread Starter
Newbie
Joined: Oct 2019
Posts: 11
Likes: 0
2008 ML320 cdi, 2001 911
Hello again,
Received the Reservoir yesterday. So i flushed all the fluid to make sure i would start on a new base, replaced the reservoir, did all the procedure to replace, test drove and no change...Since i knew the pump was replaced i did not think it could be that but still i decided to remove it. Had a check at the model number and it was a good one but for a pre 05/08. So i found a used one with about 50K on it cause i just wanted to make sure the pump would do the difference, installed it this morning and miracle, it works!!! So i now have a used new pump for sale, who would have tought that it would do such a difference, they really are the same in every way but inside must be something different.
Thanks again for your support
Patrick
Received the Reservoir yesterday. So i flushed all the fluid to make sure i would start on a new base, replaced the reservoir, did all the procedure to replace, test drove and no change...Since i knew the pump was replaced i did not think it could be that but still i decided to remove it. Had a check at the model number and it was a good one but for a pre 05/08. So i found a used one with about 50K on it cause i just wanted to make sure the pump would do the difference, installed it this morning and miracle, it works!!! So i now have a used new pump for sale, who would have tought that it would do such a difference, they really are the same in every way but inside must be something different.
Thanks again for your support
Patrick
