GL Class (X164) 2007-2012: GL320CDI, GL420CDI, GL450, GL550

Power steering pump leaking from weird place

Old Nov 17, 2022 | 02:52 PM
  #1  
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2001 S500 (W220) / 2007 GL450 (X164)
Power steering pump leaking from weird place

I had some issues with my power steering and since the beginning I have changed a lower hose, the resovior twice, the pressure hose. Now the guy is telling me the pump is leaking from some random “unserviceable” place.

my question is is there a way to fix this without a new pump? Has anybody else had a leak from this area?

also the guy was saying stay away from aftermarket pumps is that true? What about used ones?




Last edited by Mikchek; Nov 17, 2022 at 02:55 PM.
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Old Nov 17, 2022 | 08:55 PM
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No. The dude is probably wrong. it’s the $3.50 O-ring that sits up higher between the pump inlet and the Reservoir where your mouse pointer is. Or a cracked reservoir dripping down on the area you’ve circled. Do yourself a favor and try that before you get took.

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Old Nov 17, 2022 | 09:22 PM
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From: Atlanta, GA
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Originally Posted by Max Blast
No. The dude is probably wrong. it’s the $3.50 O-ring that sits up higher between the pump inlet and the Reservoir where your mouse pointer is. Or a cracked reservoir dripping down on the area you’ve circled. Do yourself a favor and try that before you get took.
Thanks for the reply! that’s actually what he just changed. That O ring was leaking so we changed the reservoir. After that he said it was still leaking and it was determined that is where is is leaking from.
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Old Nov 17, 2022 | 10:43 PM
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Well, if that’s the case, once you’ve got the Reservoir off changing the pump is a piece of cake. LUK or OEM Mercedes are good places to start, or some thing with a German name that has a warranty attached to it through FCP Euro.
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Old Nov 18, 2022 | 12:46 AM
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From: Atlanta, GA
2001 S500 (W220) / 2007 GL450 (X164)
Originally Posted by Max Blast
Well, if that’s the case, once you’ve got the Reservoir off changing the pump is a piece of cake. LUK or OEM Mercedes are good places to start, or some thing with a German name that has a warranty attached to it through FCP Euro.
thanks again! I just got it changed but it feels really stiff when I turn. I’m hoping it smooths out.
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Old Nov 18, 2022 | 08:12 AM
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Originally Posted by Mikchek
thanks again! I just got it changed but it feels really stiff when I turn. I’m hoping it smooths out.
rarely is this the case. Something else is wrong.
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Old Nov 19, 2022 | 02:30 PM
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From: Atlanta, GA
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Originally Posted by Max Blast
rarely is this the case. Something else is wrong.
I just took it back to the guy who put it in and he says because it’s only giving problems when going slow or at standstill I need a pump with higher output.

wtf I thought the pump for the car is the pump for the car
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Old Nov 21, 2022 | 09:47 AM
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You have speed sensitive variable steering.
sounds like you’re stuck in highway mode. Wheel speed sensors are the trigger for that, ensure you don’t have esp/bas cautions.

A pump is a pump - it should put out constant pressure at all rpms and should not be the cause, unless it is weak.
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Old Nov 21, 2022 | 03:03 PM
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Originally Posted by Max Blast
You have speed sensitive variable steering.
sounds like you’re stuck in highway mode. Wheel speed sensors are the trigger for that, ensure you don’t have esp/bas cautions.

A pump is a pump - it should put out constant pressure at all rpms and should not be the cause, unless it is weak.
Or it is not providing power steering boost at all, and the effect is only noticeable at low speeds.
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Old Nov 23, 2022 | 09:22 AM
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The guy is supposed to look at it tomorrow but It’s getting better over time. Is it possible there was just air in the system?

is there a way to bleed the system myself?
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Old Nov 23, 2022 | 10:20 AM
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After replacing the pump you should have left the cap off the reservoir, started the vehicle, then turned your steering full right and held it, then full left and held it. Doing that a few times should release any air in the system. Check the fluid for proper level afterwards. Rinse and repeat.
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Old Nov 23, 2022 | 10:42 AM
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Originally Posted by Miguk_Saram
After replacing the pump you should have left the cap off the reservoir, started the vehicle, then turned your steering full right and held it, then full left and held it. Doing that a few times should release any air in the system. Check the fluid for proper level afterwards. Rinse and repeat.
does it need to be in the air when you do this?
can I still do it now?
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Old Nov 23, 2022 | 10:48 AM
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Possibly air in the rack?

Yes it takes time for the air to be purged. It can be done at any time. For the sake of the rack, and tie rods, crank the steering wheel back and forth while creeping forward.
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Old Nov 23, 2022 | 08:40 PM
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Originally Posted by Mikchek
does it need to be in the air when you do this?
can I still do it now?
No, the vehicle does not need to be lifted. Just try to be on a somewhat flat surface to keep the fluid from spilling out of the reservoir.

You can perform the steps any time. Keep in mind that this addresses the possibility of air in the lines, however, there is no guarantee that it will resolve your issue.
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Old Dec 16, 2022 | 04:25 PM
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so I got the pump changed again and this time used a Bosch pump. Everything was working fine but then all of the fluid leaked out AGAIN!
After hours of searching they finally put some dye in and said it is leaking from the steering rack.
I'm so blown right now!

Is it at all possible that they caused the leak when they changed the pump, reservoir, or the pressure hose?
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Old Dec 16, 2022 | 06:23 PM
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Originally Posted by Mikchek
so I got the pump changed again and this time used a Bosch pump. Everything was working fine but then all of the fluid leaked out AGAIN!
After hours of searching they finally put some dye in and said it is leaking from the steering rack.
I'm so blown right now!

Is it at all possible that they caused the leak when they changed the pump, reservoir, or the pressure hose?
Where on the steering rack? Is it where the high pressure hose goes in to the rack? Or the low pressure hose? Or somewhere else?
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Old Dec 16, 2022 | 08:45 PM
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Originally Posted by eric_in_sd
Where on the steering rack? Is it where the high pressure hose goes in to the rack? Or the low pressure hose? Or somewhere else?
i will find out tomorrow. The notes just say on the drivers side. The leak was originally slow but what ever the did they made it faster
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Old Dec 16, 2022 | 08:49 PM
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Originally Posted by Mikchek
i will find out tomorrow. The notes just say on the drivers side. The leak was originally slow but what ever the did they made it faster
Both the high and low pressure hoses have o-rings where they enter the rack. You are supposed to change those o-rings when R&R'ing the hoses.

Not clear why they would have changed either hose, but maybe the hoses were leaking. But if they changed the hose, it should have come with a new o-ring.

And you wouldn't need to remove the hoses from the rack to change the pump. So this is a bit of a mystery..
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Old Dec 16, 2022 | 10:43 PM
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Originally Posted by eric_in_sd
Both the high and low pressure hoses have o-rings where they enter the rack. You are supposed to change those o-rings when R&R'ing the hoses.

Not clear why they would have changed either hose, but maybe the hoses were leaking. But if they changed the hose, it should have come with a new o-ring.

And you wouldn't need to remove the hoses from the rack to change the pump. So this is a bit of a mystery..
the hose was leaking pretty bad. When the guy changed it we didn’t see a leak at first.
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Old Dec 17, 2022 | 07:53 AM
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Originally Posted by eric_in_sd
Where on the steering rack? Is it where the high pressure hose goes in to the rack? Or the low pressure hose? Or somewhere else?
the tech said it’s leaking from the outer seal on the drivers side and it has nothing to do with any of the past repairs

change reservoir & a hose on reservoir
change pump
change pressure hose

he also said he doesn’t recommend the repair kit
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Old Dec 17, 2022 | 11:52 AM
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Originally Posted by Mikchek
the tech said it’s leaking from the outer seal on the drivers side and it has nothing to do with any of the past repairs
he also said he doesn’t recommend the repair kit
Sounds like a power steering rack is in your near future. I'd change the tie rod ends while you're in there.

I baby my power steering - I never turn the steering wheel when the vehicle is not moving - but still this makes me nervous. Probably ought to change my steering rack on a preventive basis.
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