Author Topic: Steering Shaft Coupling & Gearbox (Read 30776 times)

bpossel · « **on:** January 14, 2007, 07:53:03 »

Last year I replaced some seals in my old steering gearbox, only to find this a temporary fix. [

!]It started leaking again recently, so I decided to replace the steering gearbox and be done with this leak.

I finally was able to pull the gearbox out last night. A slight bit of rust was holding the gearbox to the steering coupling. Note: the box is heavy! I am sure it will be a challenge to re-install and ensure that all the alignment marks are in the right spot… I had installed the pin tool on the inside of the car, as per the BBB, but it fell out during my pulling on the box. Also, I had to use the mechanical alignment (inspection) hole, vs the power steering hole, whereas only the mechanical hole was open all the way up. No "inner" hole was visible in the power steering? Not sure why? :?: Any advice here :?:

Before I install the new gearbox, I am now thinking that, while its out, to go ahead and replace the bushings in the coupling.

I have the inside cover plate pulled up as far as it will go, which is not very far up. So being able to see what I am doing is very difficult. Also, from below (outside the car) and looking into the shaft hole opening, also very restricted.

:?: My question is… how do I remove the coupling to be able to replace the bushings? Since I have to go by mostly “feel”, I am hoping that one of you that have done this job can provide me with some guideance and suggestions.

I will take some pics and post….

As always, thank you!
Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

graphic66 · « **Reply #1 on:** January 14, 2007, 12:03:52 »

I have heard that you should also replace the mounting bolts as they can stretch and cause problems where the box mounts to the frame.

George Davis · « **Reply #2 on:** January 14, 2007, 13:49:22 »

Bob,

I may be wrong, but I don't think there are any bushings to replace in the 280 SL. Perhaps you're thinking of the bushings that the earlier cars have? The 280's have an all-metal u-joint, but no plastic parts down there.

Would you mind telling us where you got your new steering box, and how much?

Thanks,

George Davis
'69 280 SL Euro manual

bpossel · « **Reply #3 on:** January 14, 2007, 18:53:12 »

Hi George, you are correct. The later 113’s seem to have a different coupling. Seems that this later one is not serviceable, rather you must replace it…. Expense!

Here is a picture of the coupling on the car right after I removed the steering box.
Download Attachment:

view-of-coupling.jpg
37.67 KB
Here is a pic of my new steering box and my old, leaky box...
New box, nice & clean!
Download Attachment:

new-steering-box.jpg
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Old box... coughing up it's last bit of fluids...
Download Attachment:

old-steering-box.jpg
60.03 KB

With a little more persuasion this afternoon, I was able to raise the steering column cover a bit more. There was one 6mm allen bolt holding the coupling on the shaft. I removed this allen and again, with some persuasion, pulled the coupling off.
Pic of cover pulled back.
Download Attachment:

steering-column-cover-pulle.jpg
63.11 KB

Here is a pic of the coupling cleaned up. It does have some rubber bushes, but mine looked good. Maybe all the grease and crud protected them through the years? I noticed a red mark on the coupling. This matches the red mark found on the lower bolt holding the steering gearbox. It also matches the red mark on the inside wheel well where the bolt attaches. It also matches a red paint mark on my steering arm.
Download Attachment:

coupling-up-close.jpg
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Here is a pic of the coupling with bolts that hold the steering gear box in place
Download Attachment:

coupling-and-bolts.jpg
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Here is a pic of the new box installed
Download Attachment:

new-box-installed.jpg
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Some other comments on replacing the steering gear box...
When I removed the coupling and cleaned it up, I then did a dry fit to the new box. It didnt slide on... I used a screw driver and carefully expanded the coupling a bit at a time, along with some antiseize paste, I finally was able to slide it over the shaft and onto the new box. If I had not done this, it would have been impossible to install the box while trying to slide it onto the coupling.
I also did a dry fit (on the bench), with antiseize of all of the bolts, both large ones and the small 6mm allens for the coupling. This greatly helped in reinstallation. They slid in like butter during the re-installation... I will replace the large bolts that hold the steering gear box at a later time. Will remove one bolt at a time and replace.... Also note that I was not able to slide the coupling over the steering staft or onto the new gearbox with the allen bolt slightly started. They had to be completely off the coupling to install. Then had to "blindly" install them because I still could not see behind the cover plate as I was working down there.

George, I bought this rebuilt box from Mercedesparts.com. Cost me $427 (excluding core). This was the cheapest I found. The person who sold it to me said that they get them from C&M Hydraulics. Supposedly a very good company who rebuilds and tests per factory spec.

Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

rwmastel · « **Reply #4 on:** January 15, 2007, 08:05:24 »

quote:
Originally posted by bpossel

Hi George, you are correct. The later 113’s seem to have a different coupling. Seems that this later one is not serviceable, rather you must replace it…. Expense!

Here is a picture of the coupling on the car right after I removed the steering box.
Download Attachment: view-of-coupling.jpg
37.67 KB

Yes, very different indeed!

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both tops
1994 E420

George Davis · « **Reply #5 on:** January 15, 2007, 13:35:35 »

Bob,

nice pics and write up, and thanks for the info on where you got the new steering box!

George Davis
'69 280 SL Euro manual

mdsalemi · « **Reply #6 on:** January 15, 2007, 14:42:51 »

Hello Bob,

I for one, and probably quite a few others with original steering boxes, (albeit not leaky!

) would be interested to hear what your driving assessment is with the new unit in place. Did it "tighten up" the handling, or is it about the same, just without leaks?

Inquiring minds would like to know.

Kudos on the writeup and photos; good solid work indeed.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

bpossel · « **Reply #7 on:** January 15, 2007, 18:04:59 »

Hi Mike,

Just got everything back together tonight. Bled the system this morning and did a few other things while I had the front end up on jack stands... and while I had a vacation day today.

Very raining outside, so didn’t want to take for a "real" test, but I did back the car up this evening and repositioned it into its usual spot in the garage. I can tell you that it really feels very different

! It feels a lot tighter than my old box. With my old box I could wiggle the steering wheel back and forth and the wheels didn’t move. With the new box, the wheels turn immediately. I guess I would describe my old steering box as "sloppy" compared to the new box. With my old box, if I turned my wheels to their full left or right position, the system would squeal a little. Now… nice and quiet!

Probably wont take it out until the weekend for a real test. I will post an update then.

Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

bpossel · « **Reply #8 on:** January 17, 2007, 06:55:11 »

Hi All!

I called C&M Hydraulics Tech Support line last night. I believe they are in Las Vegas, not in CA.? I confirmed that they do not sell directly to the public, rather they sell through distributors. The tech seemed very knowledgeable and said that they only work on Mercedes gear boxes and have been doing this for years. I also discussed with him the leaks that I had in my old box and the fact that last year I just replaced the upper and lower seal. The tech confirmed that if the upper and lower seals are leaking, that actually there are many other seals in the box that are probably leaking. Many times the seals harden over time and just lack of use and proper maintenance (ie. Fluid changes). So just replacing the outer seals many times will not resolve the leaks. (Jeff, sounds like you did yours the right way! Complete overhaul!)

When I mentioned that my old box felt a bit sloppy, he said that this is from my “leak by” condition and with the internal leak(s), the box was not building up enough pressure. Sounds logical?

I asked him about the warranty on these rebuilt boxes and he said that it is through the reseller, so if you have a issue with the box, you work it out with the reseller that you purchased it from and they in turn deal with C&M and resolve it. The tech also mentioned that it is very rare that he sees any of their rebuilt boxes come back.

Just thought that I would share this add’l information with you…
Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

ja17 · « **Reply #9 on:** January 17, 2007, 20:27:01 »

Hello Bob,

Those fine splines make it difficult to center the steering wheel unless you carefully mark exactly how it came off. Have you had any issues here?

Joe Alexander
Blacklick, Ohio

bpossel · « **Reply #10 on:** January 17, 2007, 20:51:44 »

Hi Joe,

I actually have not driven the car yet, except to reposition in the garage. The C&M Hyd. guy said that I will need to get an alignment for sure. He said that usually the toe-in will need to be readjusted after the install of a new box.

I used a homemade pin tool in the bottom of the shaft (per the BBB), and held it in place with some duct tape, so I was able to hold the wheel in the same place. I also ensured the pitman arm was installed with the mark aligning with the shaft on the new box. The box comes delivered in its "centered" position.

So, I hope its all lined up....

Any other advice?

Thanks Joe,
Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

ja17 · « **Reply #11 on:** January 17, 2007, 23:42:38 »

Hello Bob,

As long as the wheel is centered and the wheels are nearly straight, you should be OK. If you are off more then a spline the wheel will be quite off center and the turn signal cancel will not work correctly. Unfortunatelly correction would require uncouping and adjusting as required at the splines. Very minor correction can be done with the tie rods lengths.

Joe Alexander
Blacklick, Ohio

bpossel · « **Reply #12 on:** January 18, 2007, 04:20:24 »

Thanks for the guidance and info Joe!

As I removed and reassembled my steering box, it seemed to me that most likely when these cars were originally assembled, that they: installed the coupling on the gear box in its centered position; then installed the gear box on the car; then installed the steering column with wheel; then the pitman arm…?

Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

Abbas · « **Reply #13 on:** January 18, 2007, 04:56:28 »

Hi Bob,
I have a similar problem - leaking Steering box .. do you remember what seals you changed. How many parts you had to open until you got to those seals - did you have to take the whole gear out as well.
I want to change the seals before I purchase a new one.

Here is an attachement of the Steering parts if you do not mind pointing me to the ones you changed back then. Thnks

Download Attachment:

Steering.gif
37.61 KB

Abbas

280SL W113 1969 Ivory
E280 W124 1995 Silver

bpossel · « **Reply #14 on:** January 18, 2007, 07:31:53 »

Hi Abbas,

Hard to see which seal by the diagram, but the seals I replaced was the one seal directly under the large round disk on the top of the box and also the seal directly under the lower end, under the lower plate, around the shaft area. You can see the replaced seal (blue color) on the lower end my old box (refer to attached pic).

When I did this last year, I left the box in place and only disconnected the pitman arm and unscrewed the allen bolts.

Overall a total waste of time!!!

To do it right, you really need to pull the box out and dismantle it and replace all seals. At that point I think it would also need to be adjusted per factory spec.

Jeff removed his box and replaced all the seals and had success!

I would recommend either leaving it alone and living with the leak or replacing the entire box. This is only my personal opinion based on my experience.

Bob

Download Attachment:

old-box.jpg
43.97 KB

bpossel (Memphis, TN.)
'71 280SL / '97 E320

jeffc280sl · « **Reply #15 on:** January 18, 2007, 08:52:05 »

Bob,

I'm glad your steering box replacement went well. I can't imagine a reason for needing an alignment after doing this job. I don't think any of the geometry changed. You removed the pitman arm and put it back in the same location.

Attached is a diagram of the box where your system leaked. The red o rings or seals are the parts you replaced. Anything is possible but maybe the leak occurred where I have marked in blue because the o rings marked in green were not replaced. That's the only thing I can come up with.

Jeff C.
1970 280SL 4-speed

Download Attachment:

steerbox.jpg
54.1 KB

bpossel · « **Reply #16 on:** January 18, 2007, 08:58:57 »

Hi Jeff,

Actually, Joe was right! After his post last night in regard to the steering wheel alignment, I thought I would drive it to work this morning (first real test drive due to havy rains over the weekend). Ended up turning around after a block. Anyway, the steering wheel is not lined up. Its off by about 15-20 degrees. So I will have to disconnect the coupling again, and move the steering wheel and then reconnect the coupling. I want to get it all as close as possible and then "maybe" do another front alignment?

Bummed!
Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

jeffc280sl · « **Reply #17 on:** January 18, 2007, 10:18:53 »

I thought you were referring to a front end alignment, camber and stuff. I understand the need to align the steering wheel.

Jeff C.
1970 280SL 4-speed

Abbas · « **Reply #18 on:** January 19, 2007, 12:20:31 »

Jeff and Bob,
Many thanks for this nice colored photo of various seals. Are these standard O-ring types. I guess the middle Semi-Rectangular is needs to be purchased from MB directly.

Abbas

280SL W113 1969 Ivory
E280 W124 1995 Silver

jeffc280sl · « **Reply #19 on:** January 19, 2007, 15:24:53 »

Abbas,

I would buy the MB repair kit. It used to be $24 or so. That way you get the correct o rings, oil seals and gaskets.

Jeff C.
1970 280SL 4-speed

rwmastel · « **Reply #20 on:** January 19, 2007, 22:59:47 »

quote:
Originally posted by Abbas

Download Attachment: Steering.gif
37.61 KB

Abbas,

I don't know what manual this picture is from, but it looks like part #117 is a major (complete) reseal kit. It points to a lot of parts!

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both tops
1994 E420

Abbas · « **Reply #21 on:** January 21, 2007, 03:21:26 »

quote:
Originally posted by jeffc280sl

Abbas,

I would buy the MB repair kit. It used to be $24 or so. That way you get the correct o rings, oil seals and gaskets.

Jeff C.
1970 280SL 4-speed

Jeff is there a part number for this kit I could reference.

Abbas

280SL W113 1969 Ivory
E280 W124 1995 Silver

bpossel · « **Reply #22 on:** January 21, 2007, 05:17:14 »

Abbas,

These kits are available at many suppliers. The dealer and also others. Arizona Autohaus sells them for $21 US.
http://autohausaz.com

Download Attachment:

steering seals.jpg
33.02 KB

bpossel (Memphis, TN.)
'71 280SL / '97 E320

Abbas · « **Reply #23 on:** January 21, 2007, 12:08:41 »

While searching the Steering gear parts, I found that there is yet another filter in this car that is new to me. The steering filter (as in the attached image).

Steering Filter.jpg 29.61 KB

Is this filter fitted inside the oil reservoir or somewhere else. How can you replace it ... do you also need those seals around.

Abbas

280SL W113 1969 Ivory
E280 W124 1995 Silver

ja17 · « **Reply #24 on:** January 21, 2007, 22:05:33 »

Hello Abbas,

The filter is below the metal plate in your power steering fluid canister. Remove the spring under the lid and pull the plate at the bottom of the reseviour out. The part sequence in your illustration is wrong. The plate is actually on top of the filter.

Joe Alexander
Blacklick, Ohio

bpossel · « **Reply #25 on:** January 22, 2007, 18:21:10 »

Update...

I pulled out the new gearbox this past weekend to correct alignment. When I installed it the first time, the coupling must have moved a few splines... causing the steering wheel to be off center.

This time, with the new box on the bench, and the coupling removed from the steering shaft, I installed the coupling on the steering gear box, then slide the entire box w/coupling onto the steering shaft.

The new gear box came aligned in it's neutral, centered position. It has a notch on the gearbox shaft and has a paint mark on the outer edge. This saves having to remove the standard factory nut, using the MB tool (referenced in the BBB) to ensure alignment.

Whats required is to ensure that the coupling pinch slot on the side of the steering shaft aligns with full neutral position of the box, or rather the notch & paint mark on the new box.

See attached pic which shows the coupling on the new steering gear box. The yellow paint mark came already on the box, showing the center position. The red paint marks are the ones that I put on to ensure alignment.

Download Attachment:

coupling.jpg
70.19 KB

With the steering wheel positioned to ensure the notch on the shaft was pointing up and the steering wheel was in it's true straight position, per original factory setting, the new gearbox was installed.
It was difficult to install the new gearbox with the coupling already on, but with all parts clean and with anti-seize, it all slid in nicely.

After installation, this time the steering wheel was only off a slight bit. I corrected this by shortening one tie-rod by a couple of threads and enlongating the other side by a couple of threads (~1/8 inch on each side).

Of course, I will get a professional alignment in the near future.

But for now, all is well and the car drives nicely.

Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

Abbas · « **Reply #26 on:** January 27, 2007, 04:30:10 »

Hello Joe,
I have been trying on the MB catalog to find the MB part number for the Steering Fluid filter but could not get it. Does any one have a reference number. I found part num for the cap gasket 000 236 00 80 but does not know if this is also correct.

Is there a website other than the Russian one where I can check for
this part - because I cannot seem to find the page for the s/f reservoir parts.

Abbas

280SL W113 1969 Ivory
E280 W124 1995 Silver

bpossel · « **Reply #27 on:** January 27, 2007, 06:15:15 »

Abbas,

Try Arizona Autohaus
http://autohausaz.com

Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

Naj ✝︎ · « **Reply #28 on:** January 28, 2007, 11:27:57 »

Abbas

quote:
MB part number for the Steering Fluid filter

000 236 00 55

Download Attachment:

PSF05.JPG
40.82 KB

naj

68 280SL

tel76 · « **Reply #29 on:** November 30, 2009, 21:37:58 »

Jeff,
With reference to your post #15 how do you get to the O rings in green (after the bottom cover has been removed)?

wwheeler · « **Reply #30 on:** June 15, 2011, 17:56:46 »

I am replying to this old thread because there was a question raised by Bob on his first post about the alignment bolt that was never answered.

I just removed my gear box and took pictures of the original plug bolt and the bolt I fabricated to center the gear in the neutral position (#227). I was lucky in that the gear was centered (neutral position) along with the steering wheel when it came out. I could see the dimple in the shaft through the threaded hole. To lock it in place was just a matter of screwing the altered bolt in lightly into the dimple. That dimple moves quickly so it is easy to miss! Now alignment should be right on during the reinstall. By the way, the bolt is a uncommon one. An 8mm fine thread or 1.0 pitch. Normal pitch is 1.25mm for a 8mm thread.

For the originality documenters, (#225) picture is the date in which the casting of the gear box was made. There is also a large white paint blob just out of the picture on the side of the casting next to the adjustment nut (#227).

Use penetrant on the coupling splines about a day before you remove the box!!!!!!!!!

ctaylor738 · « **Reply #31 on:** June 16, 2011, 02:52:06 »

Since this thread has been resurrected, here is my $.02.

I just finished replacing the steering coupler bushings in a 230SL. I removed the tie rod and drag link and dropped the box down. I replaced the bushings and put the coupler back on the steering shaft. I tried with no success to reconnect the box to the coupler. It seemed to me to be a "can't get there from here." There is a bulge in the steering box that fits into a groove in the frame. But I couldn't get the box into the groove without connecting to the coupler, and I couldn't connect it to the coupler without the box being in the groove. So after wrestling with the heavy box for an hour, I decided there must be a better way.

I removed the steering wheel, speedo, cluster and tach so I could access the nuts that hold the collar supporting the steering jacket. I loosened the clamp on the steering lock and dropped the jacket/shaft down and pulled it back a couple of inches. Then I put the coupler on the box, and installed the box on the frame. Then I lined up the shaft to the coupler and pushed the shaft into the coupler without difficulty.

I realize that the BBB says to do it by leaving the steering shaft in place, but this alternative worked for me. The advantages to this approach are that you can ensure that the lower coupler bolt goes into the groove in the shaft on the box. And with the mark at the top of the steering shft right in front of you, it's easy to be sure of the box/shaft alignment.

I'll take messing with the dash over dealing with the steering box any day. If I ever do another coupling, I will leave the box in place.

George Des · « **Reply #32 on:** June 15, 2012, 10:31:06 »

This is an old post, but I'll second what Chuck said in his post above. I changed out the bushings on the coupling a few years back and re-installed the box as recommended in the workshop manual. It was a real challenge and in the end it went in uncentered and the directionals did not cancel properly. It was such an ordeal to wiggle this monster in at the time, I decided to live with it while I continued to sort out other issues arising out of my total rebuild of the car. I finally decided to go back in there to fix the problem while at the same time installing a freshly rebuilt power steering box. I took Chuck's advice this time. While it was somewhat of a chore to remove the tach, speedo and center instrument cluster, it was a breeze to put the box in place with the coupling already installed in the center position and then to insert the steering wheel shaft into the coupling while looking directly at the alignement mark on the steering wheel shaft.

George

George Des · « **Reply #33 on:** November 01, 2012, 11:30:15 »

I know this is a really old topic but did want to weigh in with some info. I replaced the power steering box on my 230 SL with a C&m rebuilt unit and now have everything lined up properly so the blinkers cancel correctly, steering wheel centered, bushings on coupling tight, etc. While in there, I also replaced all three ties rods and the dampner. Short test drives showed I needed to do some slight tweaking of the toe-in but otherwise, the steering is a world of difference from what it was. Very tight and responsive like it should be. Will now get a good, professional front end alignment to ensure toe, camber and caster are set according to specs. Very happy with the C&M unit so far. Now on to have that T51-200 brake booster worked on--idle speed increases noticeably when foot held on pedal--no leaks apparent anywhere else in the lines, so i suspect a leaky diapragm

ptooner · « **Reply #34 on:** November 02, 2012, 00:45:57 »

Quote from: bpossel on January 22, 2007, 18:21:10

Update...

I pulled out the new gearbox this past weekend to correct alignment. When I installed it the first time, the coupling must have moved a few splines... causing the steering wheel to be off center.

This time, with the new box on the bench, and the coupling removed from the steering shaft, I installed the coupling on the steering gear box, then slide the entire box w/coupling onto the steering shaft.

The new gear box came aligned in it's neutral, centered position. It has a notch on the gearbox shaft and has a paint mark on the outer edge. This saves having to remove the standard factory nut, using the MB tool (referenced in the BBB) to ensure alignment.

Whats required is to ensure that the coupling pinch slot on the side of the steering shaft aligns with full neutral position of the box, or rather the notch & paint mark on the new box.

See attached pic which shows the coupling on the new steering gear box. The yellow paint mark came already on the box, showing the center position. The red paint marks are the ones that I put on to ensure alignment.

Download Attachment: coupling.jpg
70.19 KB

With the steering wheel positioned to ensure the notch on the shaft was pointing up and the steering wheel was in it's true straight position, per original factory setting, the new gearbox was installed.
It was difficult to install the new gearbox with the coupling already on, but with all parts clean and with anti-seize, it all slid in nicely.

After installation, this time the steering wheel was only off a slight bit. I corrected this by shortening one tie-rod by a couple of threads and enlongating the other side by a couple of threads (~1/8 inch on each side).

Of course, I will get a professional alignment in the near future.

But for now, all is well and the car drives nicely.

Bob

bpossel (Memphis, TN.)
'71 280SL / '97 E320

I did this job several years ago on my 230SL. It actually went pretty smoothly considering but the mark for the pittman arm was a little bit ambiguous. I took a guess and wound up one spline off. That allowed the car to turn sharper one way than the other (I forget which) so I wound up having to take it off and move it one spline. A major PITA. I didn't have to do any alignment afterwards. I removed the steering wheel while I was working on the problem and I simply lined up the front wheels straight ahead and centered the wheel when I put it back on. Interestingly, I pulled mine because of play in the steering and when I got it off I found most of the play was in the coupling and not the box. Since I already had it off and the new one in hand, I went ahead and replaced it anyway. I was hoping it would solve my chronic leak too but no such luck. I now have a set of seals for the pump and I'm working up the energy to pull it off.

Gerry

George Des · « **Reply #35 on:** November 02, 2012, 11:38:25 »

I had the same problem with the pitman arm until I cleaned it up really good and saw that there is an alignment mark scribed on the bottom surface right on the shaft bore. There is also what looks like a weld deposit on the side surface that I first mistook for the alignment mark--while it does provide a good "lead' to finding the alignment mark, if you do use it it will be about one spline off.

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