Home-made $15 W124 LCA Bushing Tool - PeachParts Mercedes-Benz Forum

Jeremy5848 · #1 07-10-2011, 01:10 AM

Sixto has written an excellent guide for replacing W124 LCA (Lower Control Arm) bushings here. I was replacing the Lower Control Arms on my '87 300D Turbo (W124, OM603) because one of the inner bushings was bad. I discovered that I also needed to replace the outer bushings, which are pressed into the wheel carrier. Unfortunately, I did not have the expensive tool needed to remove the old bushings and install the new ones and decided to build my own tool. This tool, or something similar, probably will work on other models of Mercedes.

Sixto's thread has excellent pictures of the commercial tool. I made a trip to the local hardware store and managed to make my own tool from three galvanized steel pipe fittings and several 1/2 inch bolts, nuts, and washers. The total parts cost was about US$15.

Parts List with cross-reference to part names used by Sixto to describe the commercial tool

A. 1 each 1-1/2" x 2" nipple (dual-purpose "removal receiver" and "installation receiver" Note: see text)

B. 1 each 1-1/4" x 2" nipple ("installation drift")

C. 1 each 3/4" coupling ("removal drift")

D. 5 each 1/2" bolts in sizes from 5 to 7 inches (Because the bolts at the hardware store were not threaded all the way, I had to change to shorter bolts as the bushing gradually was pushed out or in. With a bolt threaded all the way, only one is needed.)

E. 2 each 1/2" nuts (one to use and one to lose)

F. Assorted 1/2", 5/8" and 3/4" washers (they bend if you use only one)

The head of the bolt and the nut both take a 3/4" wrench. I used a 1/2" ratchet and a deep 3/4" socket on the nut plus a 3/4" combination wrench to counter-hold the head of the bolt. I put some anti-seize on the threads of the bolt(s) to reduce friction. These were normal coarse-thread bolts (13 threads per inch, I think).

To remove a bushing from the wheel carrier you need parts "A" and "C" plus two or three of the bolts, some washers, and a nut. In the next two pictures, the parts are pictured individually and as they were used, with the old bushing in the middle. Part "C," the 3/4" coupling "removal drift" was just small enough to go through the hole in the casting. That was just luck. As you tighten the nut, the head of the bolt pulls part "C" and the bushing out of the wheel carrier and into part "A," the "removal receiver."

Note that part "C" is not as slender as the real "removal drift;" it can damage the bushing as it works since it presses on the inner part of the bushing as well as the steel outside. Since the bushing being removed is presumably bad anyway, this does no harm but I do not advise using this tool to remove a good bushing. It might damage the bushing, it might not. Yours is the risk to take.

The next picture, a double image, shows the front and back sides of the casting in which the bushing mounts. The casting is part of the wheel carrier and the pictures show the tool in the process of pushing the old bushing out.

With the old bushing out, I cleaned the hole in the wheel carrier with steel wool and lubricated both the hole and the outside of the new bushing with anti-seize compound. Oil or grease, anything slippery, would probably work just as well to ease the bushing into its new home. Here is a picture of the installation tool.

The installation tool is made from parts "A" and "B," plus the bolts, nut, and washers. Part "B" is another lucky piece - it's the same diameter as the outside of the bushing so it can push on the bushing without damaging it. Unfortunately, it's just a bit too big to go through the hole in the carrier or it could be used for removal also.

When I tried to use the installation tool, I discovered why the "installation receiver" in the commercial tool has an edge cut off (see the pictures in Sixto's thread). It turns out that the front side of the wheel carrier has a reinforcing boss that gets in the way of the receiver. My receiver (part "A") was too large; I needed to cut about 1/3 off of its length and then cut an edge like the commercial tool.

Rather than do that, I decided to use part of a 1-3/4" chassis punch as a substitute "installation receiver." It fit well enough that I was able to use it without modification, saving me some time. This assembly is shown in the next two pictures. The piece from the chassis punch is on the left side. You may not have such a thing, in which case you will have to use a hacksaw on your part "A" to make it work.

Since the home made tool does not center the bushing as well as the commercial tool, you have to make sure the bushing is going in straight. My first try was cock-eyed and I had to stop, remove the bushing, and start over. The second try everything went well. Here is the newly installed bushing.

With the new bushing in place, it took only a little more time to install the new LCA and button up the suspension. Tomorrow I'll do the other side. Wish me luck!

Jeremy

1980sd · #2 07-10-2011, 01:27 AM

That's very slick! Thanks for the write up.

compress ignite · #3 07-10-2011, 03:50 AM

Youse De Man !

charmalu · #4 07-10-2011, 04:58 AM

Jerremy, another great Pictorial. this needs to be a Wiki over in the DIY section.

Would a piece of all thread work so you wouldn`t need so many washers?
When I made mine for the W123 Trailing arm bushings, I used a piece of 5/8 all thread.

Charlie

Jeremy5848 · #5 07-10-2011, 12:22 PM

Quote:

Originally Posted by charmalu

Jerremy, another great Pictorial. this needs to be a Wiki over in the DIY section.

Would a piece of all thread work so you wouldn`t need so many washers?
When I made mine for the W123 Trailing arm bushings, I used a piece of 5/8 all thread.

Charlie

The use of multiple washers was because of the span from the edge of the pipe nipple to the center where the bolt head or the nut is pressing. What you need is a 1/4 inch thick washer to take the stress without bending. You can't find those at hardware stores so I used multiple "regular" washers. (The big ones are sold as "fender washers.")

It would not be difficult (for me) to make a thick washer out of scrap metal but once you start doing things like that, your thread ends up with sentences like "First, clamp a piece of 1" steel in your Bridgeport mill." It's too easy to forget that not everyone is blessed with a garage full of tools so I try to do my DIYs with the KISS method and inexpensive materials from hardware stores and Radio Shack.

BTW, everything I did can be replicated with metric or British parts (do the cousins still use the Imperial system?) depending on what your hardware store sells. The only critical factors are the holes in the bushing and in the wheel mount casting. As long as the parts fit it doesn't matter what the numbers say. Tip: Buy the new bushings first, take one with you when you go shopping for hardware.

PS: I don't have a Bridgeport.

Jeremy

pwogaman · #6 07-10-2011, 12:57 PM

Very nice!

ronald7410 · #7 07-10-2011, 02:40 PM

Nice write-up. A mallet wouldn't be able to get that chunk out?

riethoven · #8 07-11-2011, 07:51 AM

Using the big side of a Greenlee Chassis Punch is a great idea Jeremy. I have several of them. I must have the right size. That is truly brilliant!

Jeremy5848 · #9 07-11-2011, 01:09 PM

Quote:

Originally Posted by riethoven

Using the big side of a Greenlee Chassis Punch is a great idea Jeremy. I have several of them. I must have the right size. That is truly brilliant!

I'm sure you meant "truly desperate" but thanks anyway. I used the same trick to change the spin bearings in my Maytag Neptune washing machine.

Jeremy

Jeremy5848 · #10 07-11-2011, 05:08 PM

It was fortunate that I started working on the left side of the car. As tough as that bushing was, at least it showed me that my home-made tool worked and that I could remove and install an LCA bushing.

The right side, OTOH, is much worse, possibly rusted in place. So far I've snapped in half four 1/2" fender washers (POW! pieces all over the garage) and broken a 1/2" bolt. I tried soaking the bushing in PB Blaster and heating the wheel carrier with a MAPP-gas torch but that has not yet helped. The bushing has moved a tiny bit, just enough to see, so I know it's not completely frozen solid and I think the tool is not binding. I'm using my longest (24") breaker bar on the 3/4" socket which ought to be enough leverage; the left side came out with just a ratchet.

I've sent Laura for another bolt and am making do with one of the longer bolts. The only thing I can do is keep trying and maybe see about getting the proper tool that Sixto has access to. I'd hate to break that, though, it's an expensive tool.

Otherwise, I can try to remove the wheel carrier and take it some place that has a hydraulic press. I've never removed a wheel carrier; it doesn't look like a fun job. Another option, since the bushing is not yet wrecked, is to put the car back together and take it to a shop, let them try. That will be expensive, especially if they have to take the wheel carrier off.

Am I missing anything?

Jeremy

sixto · #11 07-11-2011, 05:57 PM

You probably missed lunch

Sixto
87 300D

Jeremy5848 · #12 07-12-2011, 01:16 AM

Quote:

Originally Posted by sixto

You probably missed lunch

Sixto
87 300D

Indeed, and dinner was late too.

I rebuilt the tool using sockets, figuring a half-inch drive socket was stronger than a pipe fitting. The removal tool was made from a 1-1/8" socket as driver and a 36mm socket as receiver. The sockets also automatically center the 1/2" bolt, a big convenience. This is shown in the next two pictures.

I used the new, stronger tool to push the bushing in the opposite direction (towards the front of the car). This loosened it so that when I reversed the tool, the bushing popped free and I was able to extract it.

The installation tool was also rebuilt with sockets. I used a 32mm socket as the driver and wanted to use a 1-1/4" socket as receiver but I don't have one so I used a 1-3/16" socket instead. Once the bushing was centered in the hole and pushed about half way through, I changed the 1-3/16" socket for the 1-3/4" chassis punch and finished the installation.

I'm tired. It's been a long day.

Jeremy

sixto · #13 07-12-2011, 01:40 AM

How did you get around the gusset?

Sixto
87 300D

Jeremy5848 · #14 07-12-2011, 12:15 PM

Quote:

Originally Posted by sixto

How did you get around the gusset?

Sixto
87 300D

I'm guessing you mean that part of the wheel carrier casting that faces forward and makes centering the bushing installation tool difficult? In yesterday's work, I got the new bushing started and pulled in about half way using a 1-3/16" socket as the receiver. I wanted a 1-1/4" socket but don't have one yet. With a 1-1/4" socket as receiver, the bushing should pull all the way in.

The 1-3/16" socket does not quite clear the bushing so I had to switch to a 1-3/4" Greenlee chassis punch; it has to sit with an offset because of the gusset but it has a 3/4" center hole so the 1/2" bolt can be offset in the compensating direction. Since the bushing is already halfway through the hole in the casting, the chassis punch does not have to be perfectly centered. Crude, but it works.

Jeremy

Elvis_Presley · #15 06-19-2014, 12:41 PM

Here is my version of the homemade tool, which worked great. I considered sockets too, but didn't have the right size for the pusher (the right size could work great for the pusher, and wanted to grind off the angle for the receiver, which i think is very necessary. Also, the shorter receiver would make it much easier for the tight space. I am actually surprised it could be done with a socket.

Here is the Baum tool and my tool (pictures attached):
The only tool I used to make this was a bolt cutter (you could use a hacksaw), to cut the threaded rod, and a cheapo grinder.
1. I cut two lengths of 1/2" threaded rod. You need a longer one for pushing the old bushing out. The shorter one is less cumbersome for putting the new bushing in
2. I ground of the threads of the 1 1/4" nipple so that it would go through the hole when used to push the old bushing out. I also ground off the sharp end for a better pushing surface.
3. I used part of a 1" plumbing union as the receiver. Ground off the angle as in the expensive tool. This is necessary as there would be interference otherwise on the side that it has to go--towards the back of the vehicle.
The only issue I had was in pushing in the first one. It kept going in at an angle. I realized I needed to grind off more the angle on the receiver. Then it worked fine. R and R and the second side was easy--in under an hour.

I had most of these parts laying around. I had to go to the hardware store for the larger removal receiver (1 3/4" nipple ) and the 3/4 washers (you need two , plus one 1/2"). If you have to buy everything, I this option is cheaper than the other homemade option. 1 2' piece of threaded rod less than one bolt--and you need a few bolt in the other option. You also don't have to keep changing bolts, so it's quicker. This is how we do it "In the Ghetto".