Make your own linkage Parts - PeachParts Mercedes-Benz Forum

ujourdan · #1 08-24-2007, 12:26 PM

This is for all of you who have the plastic linkage sockets in their cars.

A while back one of my throttle linkages with the plastic ball joints broke and I was able to "fix" it with a small hose clamp. After inspecting my other linkages, all have the plastic ball joints, I found one more plastic ball joint with a crack. After trying to locate the parts for hours, I decided to make my own. I found the metal ball joints in the parts list for a 1985 Diesel on Fastlane ( C7025-26867 Throttle Linkage Socket ) and ordered a few. I got some plated steel rod from Home Depot and cut is to size and put 5mm thread on. If you do not have a metric tap and die set, just find a good hardware store and buy some 5mm threaded rod. Put the linkage sockets on with some thread locker and adjust to length and angles. I have spent $7 for the parts and now have a linkage that will probably outlast me. There are some pictures attached.

lietuviai · #2 08-24-2007, 10:04 PM

It would probably be a better idea to add a lock nut at the end of the new socket then use any lock-tite on the threads. That way you can still make some adjustments if you still need to.

ujourdan · #3 08-24-2007, 11:03 PM

Great Idea!! Why did I not think about it.... huh??
Will do it for the net one I have to replace. Thanks for the suggestion

..Udo

a2t · #4 09-04-2007, 11:21 AM

Good topic. I was driving my 87 300D turbo last night and the ball joint for the cruise control popped off the throttle linkage. Then, the rod got jammed into throttle body, leaving me at a permanent 3000 rpm. Good thing I was on highway. I drove it rest of way home, using brakes to slow back to 70 mph since it wanted to run 100 or so. Front brakes smoking badly, overheated. My dealer should spot me a new set of front brake pads!

So, I notice all the ball joints on throttle linkage are plastic, all cracked too. I don’t really care for fabricating new ball joints, but I do have 1 off an older benz that was all metal. Looks like same ball diameter as my plastic ones, don’t know about rod size though.

I will try and refit metal versions to replace plastic. Don’t want that problem ever again! Wonder if any of the metal versions fit?

nhdoc · #5 09-04-2007, 12:09 PM

Quote:

Originally Posted by a2t

Good topic. I was driving my 87 300D turbo last night and the ball joint for the cruise control popped off the throttle linkage. Then, the rod got jammed into throttle body, leaving me at a permanent 3000 rpm. Good thing I was on highway. I drove it rest of way home, using brakes to slow back to 70 mph since it wanted to run 100 or so. Front brakes smoking badly, overheated. My dealer should spot me a new set of front brake pads!

This is not a good thing to do...you could have easily overheated the brakes and lost them completely once the fluid got hot enough to boil...anytime you are faced with a situation like this the best thing to do it pull over as soon as you can find a safe place to do so and find out what is wrong that's causing the throttle to stick. Don't ever ride the brakes for an extended period. Even if you don't lose them completely you'll likely warp your rotors if the brakes got too hot and could damage the wheel bearings too...all damage that could easily be avoided.

dieseldiehard · #6 09-04-2007, 01:32 PM

I would report this incident to the dealer and copy the NHTSA, or maybe better the other way around. It clearly is a safety related failure and I am going to replace all the plastic ends on my 603's as soon as I can gather the metal ball sockets, I made linkage for my 115 when I adapted a Weber carb on it and still have some all-thread rod that was special order (don't ask, it was a heck of a lot more than threading solid rod

)
Can you imagine what an inexperienced driver might have done if this happened to someone who paniced or ran into something because they couldn't think of how to shut the engine off or worse, shut the engine off by turning the key to the lock position and thereby locking the steering wheel then coming into a curve?

As long as it goes on record eventually it gets someones attention at MB, not that they care but it might be subject to a recall if there are enough cases reported.

Hatterasguy · #7 09-04-2007, 01:38 PM

Quote:

Originally Posted by a2t

Good topic. I was driving my 87 300D turbo last night and the ball joint for the cruise control popped off the throttle linkage. Then, the rod got jammed into throttle body, leaving me at a permanent 3000 rpm. Good thing I was on highway. I drove it rest of way home, using brakes to slow back to 70 mph since it wanted to run 100 or so. Front brakes smoking badly, overheated. My dealer should spot me a new set of front brake pads!

So, I notice all the ball joints on throttle linkage are plastic, all cracked too. I don’t really care for fabricating new ball joints, but I do have 1 off an older benz that was all metal. Looks like same ball diameter as my plastic ones, don’t know about rod size though.

I will try and refit metal versions to replace plastic. Don’t want that problem ever again! Wonder if any of the metal versions fit?

You should have down shifted to 2nd. Slowed it right down, then shut the engine down, put it in N as soon as it dies so you can come to a stop. Make sure to turn the key back to the start postion so the wheel doesn't lock.

You can get new throttle links from the dealer dirt cheap, I think I paid $10 for the last one.

a2t · #8 09-04-2007, 02:05 PM

Phil sells the new throttle ball joints here

http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=22Y0KLGMW2680OMX8R&year=1987&make=MB&model=300-DT-002&category=C&part=Throttle+Linkage+Socket

But these are the same ***** plastic part that failed. I tried the metal ones I pulled from an early 80s (?) model that had metal ball joints. They fit the shaft and ball perfect, so Im trying to figure out which older style benz's used interchangeable metal.

I know about driving like that, I didnt want to. Long trip, late at night, wanted to get home. I kept revving throttle and it worked out to be holding around 2k rpm, still tough to keep fluid from boiling.

That car is on double secret probabtion far as Im concerned. I dont need anymore crap like this going up. Its funny how silly, stupid little things can get you in a lot of trouble!

Brakes, engine, OK. I was letting off, letting cool for 20 sec inbetween. Thankfully Atlanta traffic moves quick!

I dont really see how I can blame MB, this car has 261k miles on it. Stuff breaks eventually...

dieseldiehard · #9 09-04-2007, 02:55 PM

Older Mercedes all the way back to the late 60's used the metal ball joints, its too bad they went to plastic in the 124 chassis, what could that possibly do? lower weight, naw theres only a few grams involved, it had to be lowering the cost, presumably to increase profits for the stockholders or Schrempp?

Here's an excerpt from BusinessWeek mag:
Q: Why were Schrempp's deals a mistake?
A: They were a mistake because the strategies –- for Mercedes and Chrysler and all of its associated brands -- were so different. For years, Mercedes' car brand sat at the top of the world as far as prestige, durabilty, and reliability. Starting in the mid-1970s through the mid-'90s, with the iconic 450-series, it was the ultimate car brand. It was the finest-engineered car you could buy.

Contrast this with Chrysler. During the same period, it was constantly looking for what rabbit it needed to pull out of its hat to stay alive. Were it not for the minivan, introduced in 1982, Chrysler would have been gone sometime in the 1980s. Schrempp has done a great deal of damage to a company that had a rock-solid reputation by cobbling it together with a company that slithers from crisis to crisis. We have a huge mismatch here.

DDH

Hatterasguy · #10 09-04-2007, 09:36 PM

My car is 20 years old and I have only had to replace one linkage. But it was my fualt because I broke the plastic ends.

In my book any part that lasts 20 years owes no one anything. Nothing lasts forever.

Lube them with a little ATF once in awhile and don't break them, they will last a damn long time. And when they break they are cheap to replace. Whats the problem?

a2t · #11 09-06-2007, 06:33 PM

Quote:

Originally Posted by Hatterasguy

My car is 20 years old and I have only had to replace one linkage. But it was my fualt because I broke the plastic ends.

In my book any part that lasts 20 years owes no one anything. Nothing lasts forever.

Lube them with a little ATF once in awhile and don't break them, they will last a damn long time. And when they break they are cheap to replace. Whats the problem?

The problem is when they do break you'll find yourself going 70 mph, some minivan pulls into fast lane going 50, you hit the cruise off button and nothing happens cuz the linkage popped off and jammed into throttle body, then you almost rear end em.

But I agree, if the plastic ones last 261k miles, how much more can you ask?

Well, I can ask for the metal ones, I guess. But if not, then I guess I will opt for plastic.

So...do the metal versions from 123 fit my 124 or not?

a2t · #12 09-15-2007, 11:33 PM

OK I got the metal ball ends from an 81 300D at the dealer. They fit my 87 300D turbo just fine, threaded right onto the rods and all.

Cant say this learning process was fun, but hey, at least I got genuine MB metal rod ends for all of $2 a piece with my dealer discount

.