Tight Steering - Rebuilt Box - PeachParts Mercedes-Benz Forum

BIGRED · #1 07-21-2007, 02:29 AM

Hi All...

I rebuilt my entire suspension front and back. The only thing not replaced were the springs and the bearing holders for the front end.

While I was at it, I installed a rebuilt steering box. The car was on blocks for weeks. After driving it I noticed the steering being very stiff so the company sent me out a replacement. Still stiff. I checked my idler arm and steering damper for binding and correct torque All OK there....So I tried to loosen the box a tiny bit... no change.

The thought hit... what about the power steering pump? No leak, no weird nose, but I don't know the symptoms when they start to fail. I don't that the tools to test the pressure on it so any help or suggestions will be really appreciated.

Thanks in advance
Don

sixto · #2 07-21-2007, 02:31 AM

Did you bleed the pump?

Sixto
87 300D

BIGRED · #3 07-21-2007, 02:33 AM

I assumed it bled it self....nope didn't bleed it.

BIGRED · #4 07-21-2007, 02:38 AM

Just read about it in the shop manual... the right to left and left to right.. yes I bled it. Also have about 200 miles on it.

Thanks
Don

Ara T. · #5 07-21-2007, 04:01 AM

Are you sure your old box was so sloppy that the new one feels too stiff?

t walgamuth · #6 07-21-2007, 06:36 AM

I put a rebuilt box in my two forty many years back and it took a year to lose its tightness.

I have not installed a rebuilt since, always being able to improve it significantly by adjusting.

Tom W

BIGRED · #7 07-21-2007, 08:58 AM

Quote:

Originally Posted by Ara T.

Are you sure your old box was so sloppy that the new one feels too stiff?

Yes..... I have to work the steering wheel in both directions... it doesn't find center well.

BIGRED · #8 07-21-2007, 09:05 AM

Quote:

Originally Posted by t walgamuth

I put a rebuilt box in my two forty many years back and it took a year to lose its tightness.

I have not installed a rebuilt since, always being able to improve it significantly by adjusting.

Tom W

My old one had its screw backed out all the way. the box was dead.

A year...oh my. If its the box and not the PS pump, then I wonder if the large nut (#17 in the pic) is a bit tight?

cscmc1 · #9 08-09-2008, 02:09 PM

OP -- did you ever rectify this? I am encountering the same issues. Thanks!

t walgamuth · #10 08-09-2008, 06:15 PM

I have two excellent used boxes for sale in parts for anyone considering buying a new one.

Tom W

David4 · #11 08-09-2008, 07:46 PM

Hi Where did you guys get the rebuilt steering box? How much was it? I need one too for my 82 300D

Thanks

Hatterasguy · #12 08-09-2008, 09:51 PM

I rebuilt my own and was pretty pleased with the results.

Considering the parts that wear inside the box are about $490 to replace...I doubt they are true rebuilds unless you are paying $700+, more like a cleaning/adjustment and reseal.

FYI you can order just about every part inside and on the box from MB.

http://www.davidpetryk.net/Mercedes/Steering.htm

I did it myself for the price of a seal kit, if you are mechanicly inclined enough I recomend at least giving it a shot.

BENZSTER · #13 09-11-2008, 07:06 PM

Hatterasguy,

I'm curious as to which parts you replaced to "rebuild" your box. Would they happen to be item #56, the pinion gear and rack assy. as in post #8 above? These are the parts that I am considering replacing in the steering box on my '81 240d. I replaced the original with a rebuilt unit a couple of years ago and now there is no more adjustment left. I have about 3" of side to side steering play, not very comforting to drive. I've tried going down the rebuilt steering box route again this time but I'm finding that there ain't much rebuilding going on. I've tried two different boxes from same rebuilder and one from another, all are the same crap, after installation and alignment no noticeable difference. My front end was totally rebuilt approx. a little over a year ago so there is nothing else going on to cause the excessive play. When you receive the so-called rebuilt unit the first thing that catches your attention is the amount of adjustment bolt threads that are exposed. Really no adjustment left, which is telling me these are all just a re-seal and pretty paint.
What really gets to me is what MB wants for a replacement steering box, if you don't believe me check it out for yourself. New box = 4400.00 or new MB rebuilt = 2600.00 Sorry, but this is no vintage 300sl this is a mass produced car.

Brgds,

BENZSTER

Hatterasguy · #14 09-11-2008, 08:11 PM

Thats a lot, the dealer wanted $1,700 for a new box for the SDL. They don't offer rebuilt anything anymore.

I typed that wrong, I resealed mine, I bought the $19 kit that Phil sells and cleaned everything up, than adjusted it. Its got about 180k miles on it, and is tight enough, but not perfect.

The pinion gear and circulating ball assy is where you will find all the wear, on the W126 they run about $500. I really doubt that most rebuilders change those, more likely than not they simply use the good ones from the used boxes they get and scrap the rest. Unless you are paying $800 for a rebuild that is, than maybe.

If you can find a junked lower mileage W123 with tight steering, than reseal it with that kit you might be happy with the results. For $20 and some time I figured I'd try it before buying a new box.

BENZSTER · #15 09-11-2008, 08:45 PM

I've looked through the local junk yards and everything I can find appears to be adjusted out to the max, meaning to me that a re-seal is not going to be my answer. I agree that most of the wear should be between the gear and rack assy. It looks like when you adjust the box, the pinion gear is being moved to hopefully a new unused section on the gear face thereby reducing the play. Notice the pic of the pinion gear assy.appears to be wedged shaped.

(http://www.davidpetryk.net/Mercedes/Steering.htm)

I'm thinking this is to accomodate for anticipated wear and adjustment. After talking with a couple of independant shops they are telling me that the rebuilt boxes that they use for customers cars are all the same a very hit and miss process on getting a good rebuilt box. They have also told me that w123 boxes seem to wear faster as say opposed to a w126 box which to me appears at least from an outwardly appearance to be very similar. Maybe a higher internal movement ratio makes it wear faster? For me, replacing the pinion gear and rack assemblies seems to be the logical fix at this time unless some one here has a magic fix.

Thanks,