S-Class (W220) 1999-2006: S 320 CDI, S 320, S430, S 500, S 600

Power Steering Leaks

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Old Oct 6, 2014 | 07:50 PM
  #1  
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From: Hickory, NC 28601
S500
Power Steering Leaks

My 2001 S500 p/s leaked really bad. I have checked the reservoir, pump, and the lines come out of it - no leaks or cracks. I traced back to the two copper lines that connected on top of the steering assembly. I hope this make sense. I really don't know what is the proper name for it. See attached picture (you can see the lines on the right and above of the inner tie rod).

My questions are:
1. Can the experts help to provide p/n forthe gasket or the whole line?
2. Is there a special tool I have to purchase for this nut?

Thanks in advance.
Attached Thumbnails Power Steering Leaks-img_2608-1-.jpg  
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Old Oct 7, 2014 | 02:15 PM
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From: New England
2006 S430 4Matic
Those are banjo bolts. Most likely a torx bit. They have to be tightened down. You may have a problem getting something in there. You may have to remove some items to get to it. Make sure you use the correct fluid to top it off.
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Old Oct 7, 2014 | 10:16 PM
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From: Ball Ground, GA (N of Atlanta)
2003 S500 2007 GL450
Using a 1/4" bit that fits the fastener, and turning it with a 1/4" box-end wrench (ring spanner), or a 1/4" socket in a pull handle, would be my approach.
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Old Oct 9, 2014 | 06:31 PM
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From: Hickory, NC 28601
S500
Got the metric Allen stubby today, used 6mm tighten it almost 3/4 turn. Top off p/s fluid, crank the car and it still leaked. Can anyone help what the p/n for the O ring for this banjo fitting? Thanks in advance.

PS. I used part.com but doesnot show the details.
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Old Oct 15, 2014 | 10:40 AM
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'03 S55 (79K miles)
I don't know the oRing pn. And I don't have personal experience (yet) on PS for this connection.

Is it rubber oRings there? Usually banjo bolts have copper or aluminum crush washers on both sides of the banjo.

If indeed rubber, your ps fluid is Pentosin CHF-11S, you would need to be sure to use Viton-based material. Natural rubber can get hard and crumbly in the presence of Pentosin CHF11S, a synthetic hydraulic fluid.
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Old Oct 16, 2014 | 05:35 PM
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From: Hickory, NC 28601
S500
I decided to fix it this weekend - The problem solved.

The fix is quite simple (you don't have to remove the steering gear assembly braket, but can make the job easier):

1. Place the vehicle on jack stands. Place a catch pan directly underneath of those p/s hoses
2. Remove both banjo bolts (Thougt only one banjo fitting was leaked on mine: if you don't remove the one from the left, it's impossible to take the bolt out of the banjo fitting). You have to pull the p/s hoses away from the engine block and wiggle it around to get clearance to take the bolts out. Start witht the one on the right.
3. Use a tooth pick to remove top and bottom O-rings (is not a crush wahser). See image IMG_2696
4. Clean the sourounding area
5. Clean and apply small amount of P/S fluid on the new O-rings. I bought the kit at Adavance ~ $15. See attached for part number. Make sure to match the correct size.
6. Reinstall O-rings in the banjo fitting. Try to get a feel how the top O-ring is install. The bottom one is a little tricky since there is not much room to get your fingers behind it.
7. Pour some fresh p/s fluid in to flush out the old one. This step you don't have to, but since you are there already why not flush the system out. I know, CHF11S is expensive. You can get on the net for $20, however, I didn't have the time so I decided to purchase at Advance for $25.
8. Clean and reinstall the bolts. The easiest way for me is to get the bolt on the right in first, finger tight, then install the left bolt.
9. Top off p/s.
10. Without engine running, turn steering wheel L then hold for few seconds. Repeat this step for R. You can check the resevior and see alots of air bubbles.
11. Top off if needed, close the cap, crank the engine, turn steering wheel L and R couple times. Turn off engine check p/s fluid, top off if needed.

Congrats.

Hope this will help someone with the same problem.
Attached Thumbnails Power Steering Leaks-img_2696.jpg   Power Steering Leaks-img_2697.jpg   Power Steering Leaks-img_2698.jpg  
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