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Discussion Starter #1
I have just recently replaced the steering box because it was leaking, and now there is this loud humming noise when i turn the steering wheel to the left or to the right. Could it be that the power steering pump needs to be replaced also ?
 

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Discussion Starter #3
Did you bleed the air from the system? Also did you replace the old fluid with new fluid that meets spec?
Yes new fluid was replaced. I do not know if my mechanic bled the air from the system. Do i need to go back to him, or is this something i can do on my own ?
 

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You can do it yourself but since you paid the mechanic to do the job, it should really be done by him. That's part of the job. See if he bled the air out and ask him what type of fluid he put it.
 

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Discussion Starter #5
You can do it yourself but since you paid the mechanic to do the job, it should really be done by him. That's part of the job. See if he bled the air out and ask him what type of fluid he put it.
I brought him the original Mercedes fluid. Can you guide me with the bleeding process ?
 

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Jack up the front of the car. The front tires should not be touching the ground. You don't have to do this, but it makes turning the steering wheel easier and faster. Open the power steering reservoir cap. Start the engine. Then turn the steering wheel from lock to lock 9 or ten times.

Go check the reservoir and see if the fluid level is the same. If it is the same then most likely there isnt any air in the system. If the fluid level is lower, that means there was air in the system, and it came out. If you see this then you need to add fluid, and repeat the same steps of turning the wheel from lock to lock. Continue doing this until the fluid level stays the same.

It would then be a good idea to go on a drive for a little while (15 minutes). When you go back home check the fluid level again after your drive.

Hopefully this will solve the groaning problem.
 

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Discussion Starter #7
Is there a reason i should jack up the front tires ? I did not jack up the front tires, removed the cap with the engine running, and turned the steering wheel all the way right and left 2-3 times. I still get that noise. The power steering fluid seems to be the same. Do i have to turn more times the steering wheel ?
 

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Well it just makes turning the wheel easier. You don't have to jack it up. I would turn it lock to lock a few more times to be sure.
 

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Couple of things.

First it is very common to need a power steering pump rebuild directly following a steering box replacement due to the much higher pressures from the rebuilt box.

Second, as I recall if air is introduced in the system it is very difficult to remove and requires 30 turns full lock to lock

Seth
 

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Discussion Starter #11
Couple of things.

First it is very common to need a power steering pump rebuild directly following a steering box replacement due to the much higher pressures from the rebuilt box.

Second, as I recall if air is introduced in the system it is very difficult to remove and requires 30 turns full lock to lock

Seth
What will happen if i don't rebuild the power steering pump, and i just leave it like this for now ?
I did the 30 turns full lock to lock, and the power steering fluid level is the same and the sound still exists when i turn the steering wheel.
 

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So there is no foaming in the reservoir?

Would be ok to drive for the time being. They usually get louder over time and you may start to experience abnormalities when turning the wheel
 

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Discussion Starter #13
So there is no foaming in the reservoir?

Would be ok to drive for the time being. They usually get louder over time and you may start to experience abnormalities when turning the wheel
There is no foaming at all in the reservoir, and the fluid level has stayed the same.

If i just drive like this for a while, it will not cause any damage to the recently replaced steering box ?
 

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I would follow the suggestion made in post #4. Take the car back to the shop that did the work.

Sent from my XT1080 using Tapatalk
 

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Not sure if this will help but awhile back i had my power steering pump replaced and mechanic put the PS fluid in wrong tank he never worked on these cars and its pretty hidden so make sure youre checking the right reservoir it should be under the plastic cover with the star on middle of the engine. sounds pretty dumb but it happened to me so hopefully it didnt happen to you.
 
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