It's doable but a PITA. The shaft that comes from the steering wheel (with the 2 flats on it) will telescope into the column. I had to carefully use a pry bar to slide it up towards the wheel.

First remove the allen bolt that connects the coupler to the steering box. You can then pry against the coupler and move the shaft towards the steering wheel until you have enough room to take out the top bolt and slide the coupler out.

Mark it well! Once you get the coupler out and if the wheel isn't locked it will spin freely and make getting the wheel straight a REAL PITA!

For installing it slide it onto the steering wheel shaft, replace the allen bolt and pry it back down onto the splines. You'll swear it'll never slide back down but it will.

I used a flashlight to check to make sure the "slot" on the steering box was aligned so the allen bolt would go in.

Make sure you get the bolts back into the slots! You don't want that sucker rattling loose

I adjusted my steering box and fixed the coupler and it drives soooo much better!

Someone else may have a better procedure but this worked for me numerous times. MARK IT so you don't have to do it numerous times

Remember, 116's are the best!

Oh yea, I did it all from under the hood.

Good luck!

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

Yes, they are.

So I should lock the wheel before I start to make this easier? Red nail polish
to mark it?

Thanks!

__________________
Ginny in Denver-ish
78 300SD, 265K (mine)

I'd say lock the wheel and mark it with something that won't rub off easy. Maybe check the marks right before you slide the coupler off.

I didn't mark mine and it took about 4 or 5 tries to get it straight The tires looked straight, the wheel looked straight but when I drove it the steering wheel was crooked.

I got good at pulling the damned thing though

When I did my driveshaft bearing I marked it with spray paint. Maybe line up the "crack" in the coupler and hit it with a spray bomb? Thank God I marked THAT!

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

Side load on the bearing.

Can you prove that the gearbox and column are in perfect alignment and that the body does not flex with load and road forces?

The truth, your post was outright dumb and warrants your addition to my Ignore List of Shame. 1980sd has a valid alternative that is both cheap and retains near-stock functionality.

Ah, yes, I recognize that 300SD now.

I used a bit of fuel hose in my W116 coupler when I rebuilt it.

Now I need to replace the one on SWMBO's R107 ( 380SL) . That's not gonna be fun....

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)

So I got some photos of my coupler and a video of it in motion.
My rubber parts are toast. And when it was put in (or back in)
the allen heads are UNDER instead of reachable from the top.
CRAP!

__________________
Ginny in Denver-ish
78 300SD, 265K (mine)

Turn the wheel and get them pointed up

I'd spray the whole thing with some penetrating oil and let it sit before tackling it. I used an allen wrench with a piece of pipe for a breaker bar to break the bolts loose.

It'll be worth it!

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

Duh! LOL!
Will do!

__________________
Ginny in Denver-ish
78 300SD, 265K (mine)

I would enjoy being placed on your ignore list....

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Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

I did my w116 coupler today. Followed Kerry's instruction on removing wheel and coupler. One caveat: I did remove the four bolts that holds the turn indicator part, and that gave me the room I needed to remove and install easier. Road trip was incredible; like a completely different car! The responsiveness is great, I don't have any more noise in the cabin than I did before (door seals are slated for summer.. ), no buzzing in the wheel. I did notice that I have a little play in the steering box, that can be addressed at a later time, its not much.

Thanks Dokter Bert!

OP and those who have done this mod, any ill effects after long term use? I think I will be doing this tomorrow.

__________________
http://closeupcleaners.com/benzsig3.jpg
'96 S420 - 126k
'73 450SEL (Sold)

Did it, and it totally changed the way the car drives. My coupler had no rubber left whatsoever, so you can imagine the amount of play I had. Feels like driving a new car.

One question though. Everything is buttoned up but I can still see about half an inch of shaft coming out of the steering box, unlike the picture in the SD1980 posted. Is it supposed to be that way or is my coupler not on the shaft all the way?

__________________
http://closeupcleaners.com/benzsig3.jpg
'96 S420 - 126k
'73 450SEL (Sold)

Excellent thread, great pics. I've had the same rattling, and after reading this thread and one more I'm convinced this coupler is the culprit. Like someone else, my Allen bolts are facing downward, but I also don't really know much about the components of the steering column and even what a coupler does/is. What's the main difference between these two methods of repair (dokter bert's vs. the one 1980 300sd posted)? Which is easier? I'm very new to this and have limited expertise.

Thank you!

Ok, my worn out coupler is definitely the cause of the rattling, so I'm trying to replace it. Because it seemed like the 3/8" bolts with 11/32 brake hose was the easier repair, I decided to go that route. Well I haven't gotten very far. I can't get the 2 allen bolts off that hold the coupler on. I did like someone suggested and sprayed on (a bunch) of penetrating lubricant, let it sit, even bought a set of allen wrench sockets for my 1/4" ratchet (couldn't find them in metric for my 3/8" ratchet). It is righty tighty lefty loosy here, yes?

Next step is a breaker bar, I guess, for more leverage...any ideas on how much I should pay for one of these, or if there are any other tips I can try?

__________________
1980 300SD Turbo Diesel
"Bailey's. Mmm...creamy. Soft, creamy beige." - Old Gregg

I finally was successful in getting the steering shaft telescoped enough into the column that the coupler (still attached to the steering rod) is separated from the male part of the gear box (splines?). But I can't get the coupler off still as I can't move it up / down / to either side enough for it to get clear of that part coming out of the gear box. Is there something I missed? I followed someone's instructions here (mostly, except I took both Allen bolts off at once, oops) and pried it toward the column till it was separated. Of course now I've messed with it so much that it's not gonna line up right, but I don't think I got to the point where I could mark it. sigh...my mechanical skill is only enough to get me in trouble.

So now I'm stuck under a tree in the side yard until I can get this thing done...at least it'll make me stick to it!

__________________
1980 300SD Turbo Diesel
"Bailey's. Mmm...creamy. Soft, creamy beige." - Old Gregg