Rebuilding entire suspension 87' 560SL. Tips, Pointers and HELP! - Page 2 - PeachParts Mercedes-Benz Forum

david s poole · #16 09-23-2006, 11:27 AM

one thing that will make life a lot easier here is to completely remove the front sway bar.if you do the subframe will hang down all by itself one side at a time.it will be low enough to allow easy access to the motor mounts.when i do this job i am not usually removing the lower control arms so i just unbolt the sway bar brackets from the front horns on the chassis rails.

red560SL · #17 09-23-2006, 02:56 PM

That's exactly what I did David. I found out early that the frame wasn't going to get past it if I didn't. Four quick bolts and it's out. Piece of cake.

-Tony-

red560SL · #18 09-24-2006, 10:22 AM

I'm very careful when working on cars or when doing anything that could be dangerous. I'm in my late 40's and have never broke a bone, had any kind of surgery or even a cut. Well the Mercedes changed my near perfect score.

Yesterday I was in the middle of changing the bushings in the Idler Arm. Those darn things are frozen in there. I was able to get the top bushing out by using a flattened punch from underneath. I soaked everything with liquidwrench for hours. The top took me at least an hour to get out. Next I needed to get the bottom bushing out. What I did was use the old bolt that came out of it. The bolt would fit through the hole and stop at the bushing which was perfect. I tried coming in from the top and extended the bolt out the bottom. I then strapped a piece of iron with a hole in it for the bolt to pass through. The iron would then fit accross the frame. I then took a hammer and kept striking the bar. My hammer struck back and hit my hand. I was weiring super strong nylong gloves to help keep my hands cleaned. I saw that the glove was not cut so I felt the pain would go away and it was nothing major. My glove started to feel like a sponge. I started to take off the glove and blood started pooring out. It kind of put me in shock for a second. I rushed inside and started irrigating the cut and saw that it was quite deep and bleeding very badly. I wrapped it up and headed for urgent care. Well here I am the next day with 4 stitches in my hand. It wasn't until after I arrived at urgent care that I remembered I had taken 3 aspirin about 2 hours earlier. No wonder my hand was bleeding so badly. The doctor said that it was probably good it was bleeding like that as it kept the cut clean.

The moral of this story is, no matter how cautious you think you are, you're not cautious enough. This is the last thing that needs to be removed and I can then begin re-assembling everything. Now I'll be forced to step away for a few days so I will not be able to update you wonderful Internet Mercedes freaks on my progress. I know I'm just going to love this car when I'm done. Can you believe I've only driven the car twice since I've owned it? I didn't want to cause any additional damage so I saved some money for the repair work and hear I am.

I just wanted to let those who might be following this thread what happened so you don't think I'm SUPER SLOW at repairs by not updating this until the middle of next week. Sure I'm slow, but not that slow.

Have a great Sunday everyone,
-Tony-

Strife · #19 09-24-2006, 12:12 PM

Sorry you got hurt...please don't think people will think that you are slow. I probably take 2-3X shop time to do some things. Frankly, I don't care. I will do things slowly, and by the book on this car (for a CHANGE). I look at maintenance on this car as a continuous process, not as a "do it all at once" (except where practical because of the proximity of other tasks) sort of thing.

david s poole · #20 09-24-2006, 12:43 PM

sorry to hear about your mishap.my hat is off to anyone who would attempt these repairs without a lift.

red560SL · #21 10-05-2006, 07:12 PM

Well the stiches are out of the hand and I'm back to work on the suspension project. I finally got that idler arm bushing out and the new set all in. Subframe all assembled, tie rods in, upper and lower control arms in, shocks, ball joints, driver's side wheel bearings and roter all installed. All I have left is one tie rod on the passenger side, hub and wheel bearings and rotor as well as the breaks to be installed. I'll finish all this once the four lower control arm cam bolts and nuts arrive (see my warning).

WARNING - The Mitchell CD Manual has incorrect torque specifications for the lower control arms. It states they are to be torqued at 133ft pounds. I thought this was high and even tightening I felt it was too much. In the process of torquing to these specs I stripped a nut. I replace it with another and went to the next one. I decided to torque it a bit less at 150ft lbs and have it retorqued at the service center when I have it aligned. On the last nut I busted the bolt in half! This was lucky on my part because I found out these specs are completely wrong!!! I decided to purchase another manual and bought the manual at Manuals Unlimited. First off it's a much better manual and is the actual shop manual. I looked up the torque specs and these are to be torqued at 88ft lbs and NOT 133ft lbs as specified by Mitchell.

Since I have over torqued these bolts I have stressed them and they are no longer safe in my opinion. Because of this I have reordered the lower control arm cam bolts and nuts. I should have them here by Monday and I'll finish this frontend up. It's just one delay after another I guess.

Now I have a question for you professional machanics or extreme weekend machanics. How in the world do you torque the lower control cam bolts that are in the front of the car? These are 22mm nuts and there is no way to attach a socket to a torque wrench and fit it in the space that's available. Even dropping the sway bar won't help. Is there some special torque wrench or additional tool needed to do this? I have no problem torquing the rear nuts, but with what I have right now it seems impossible to torque the front. Do you just torque the back and get a feel for the pressure and then tighten the front based on the feel/pressure you had on the rear?

I've attached a couple of pics so you can see where I'm at.

Thanks guys,
-Tony-

Richard Wooldridge · #22 10-06-2006, 01:53 AM

Hi Tony,
Looking Great!

Its nice to see all those new parts in there. On those lower control arm bolts, would they fit in from the opposite direction, and would that make a difference? When I replaced the sub-frame on my '82, I didn't bother with a torque wrench, just tightened them until they felt "right", and they've been fine. I imagine you will be taking it to a shop for a front-end alignment soon, maybe if you just do the same the shop will take care of the adjustments and torque everything properly all at the same time. Or, maybe not...

red560SL · #23 10-06-2006, 02:28 PM

Thanks Richard. That's about what I figured. I can go from the opposite side and I thought about doing it that way, but I also thought that by doing it this way the cam on the bolts would then be in the opposite direction. I'm thinking those cams are there for a reason and didn't want to switch the dynamics. On the two rear facing cam nuts I can torque without a problem so I'll torque those to the proper specs and get a feel for it. Then I'll just feel the settings on the front (maybe a bit less than what I felt). When I go in for the alignment I'll ask them to check all the torques. I've decided to go to the dealer as Mercedes is special and requires special equipment. Heck just look at that super expensive $1,100 spring compressor they have (ie, Klan):

http://www.samstagsales.com/klann_spring.htm

I found a knock-off for under $250:

http://www.toolss.com/wbstore/main.asp?ACTION=PROD&TYPE=&CTMP=1&CAT=&SUB=&PROD=924-0231&Search=&LowCt=0

This does NOT work for the front springs and even the Klan doesn't work for the front. For the front springs you just have to raise the car high enough and swing the lower control arm low enough to pull them out. To be safe I used a C-clamp at the top of the spring and spring housing to hold the spring in so that when it pops out it doesn't shoot across the room. It worked great! To put the spring back in I removed the compressor. Went together like a charm.

I just received the new cam bolts so I'll going to try and finish this up today. Then I'll be moving on to the rear of the car. Boy that looks scarry!

Did you notice the electrical wires hanging down are all newly shrink wrapped?

http://www.peachparts.com/shopforum/attachments/tech-help/36871d1160089730-rebuilding-entire-suspension-87-560sl-tips-pointers-help-dside-4.jpg

While waiting for the new cam bolts I decided to remove the hardened wrap that was on the wires and re-shrink wrap them. It gave it a nice polished look and will help protect those wires for a few more years. I used a high tempurature shrink wrap.

Thanks
-Tony-

red560SL · #24 10-10-2006, 07:25 PM

Well the front suspension is 98% completed. I have everything together except for the calipers. The reason the calipers are not yet on is because I noticed the rubber dust covers on the pistons were rotted and/or dried. So I ordered a rebuild kit and will complete that when the kit comes in. I believe the kits will arrive tomorrow. From what I understand I'll have to adapt a line from my air compressor to the hydraulic line to the caliper. Then I'll put the caliper over the old rotor with the old pads and add air pressure which will extend the pistons out. At that time I'll evaluate whether to extract the pistons and go through it or just replace the outside rubber covers.

Anyway I decided to get started on the rear of the car. My plan for the rear is similar to the front:

1. Replace Trailing Arm Mount Bushings

2. Replace Subframe Mount Bushings

3. Replace Differential Mount Bushing

4. Replace Rear Flex Disc (front one already replaced when I went through the tranny)

5. New Rotors

6. New Disc Pads

7. New Parking Brake Pads & Springs

8. New Wheel Bearings (more on this)

To do this job I found I had to remove the exhaust system and loosen the emergency brake cable so that you can feed the cable through the rear hub to remove the drift pin in order to take out the emergency brake cable.

I also had to remove the rear flex disc from the differential. The reason for this is that you can't remove the Trailing Arm Mount bolts as they will hit the disc. Removing the flex disc makes it pretty easy to slide the bolt out. To do this you have to loosen the driveshaft mount so that you can slide the driveshaft forward enough to remove the flex disc.

Once the caliper and rotor/drum is removed, I took out the center screw holding the axle and slid back the axle . I then removed the emergency brake cable and removed the upper sway bar link from the trailing arm. The next step is to remove the shock. What I did was loosen the two nuts on the bottom of the Trailing Arm, but did NOT remove them entirely. I then removed the back seat (or lack of one) and the side trim in order to get at the top of the shock mount. Next I used a floor jack to support the Trailing Arm so I can safely remove the top nut of the shock. Once removed I released the jack pressure and removed the two nuts on the bottom of the shock. Keep in my that my car is about 2 1/2ft off the ground. You'll need this distance in order to slide the shock out from the bottom.

Now that that shock has been removed it's now time to use that $250 spring compressor tool I bought. I provided a link to this above. This worked perfectly!!! I colapsed the spring, lowered the jack and removed the spring without any problems at all. This was much easier than the front spring (you don't use a compressor for that one).

Now the Trailing Arm is completely free other than the two 24mm nuts and bolts connected to the subframe. Removing these two nuts is a real *****. What I did was support the rear subframe with a floor jack and removed the subframe mount (see pics). Doing this allowed me to lower the subframe just enough to give me the room needed to slide the bolts out. Once out all I had to do was give it a little bit of a wiggle and the entire Trailing Arm came out. At this point you really don't need to keep the jack since the other side of the subframe was not removed and can easily support this.

red560SL · #25 10-10-2006, 07:29 PM

So now the Trailing Arm on the driver's side has been completely removed. The next step would be to replace the wheel bearings. I've read several posts in this forum regarding this procedure and some would like you to think this is not a DIY. I however believe anything can be done if you just take your time and have the right tools. My plan is not to actually do the wheel bearings myself. Instead I'll have a local machine shop do the removal and installation of the new bearings and seals. However the removal of the flange requires a special tool called a "Pin Wrench Socket". For this vehicle it requires the SIR tool M 0027 which I purchased here:

http://shoptoolsshoptools.com/shopexd.asp?id=1051

This special tool fits the back side of the flange where the axle goes in. I have attached a picture so that you can see where this little tool goes. This nut is on pretty tight from what I understand and like everything else Mercedes, they have a special tool you can attach to the flange with a breaker bar and turning this nut will separate things. However you can also thread bolts through the flange and use a pipe to achieve the same thing or just weld a piece of pipe to an old drum and you're good to go.

My plan is not to do this work myself. Instead I plan to take the Trailing Arm along with the flange and the special socket to my local machine shop and let them take care of all this. Since this is a Mercedes we are talking about, and we all know how "special" these guys are, I'll print out the shop manual explaining all the steps required for replacing the bearings. When doing this you must replace the rear axle tension crush spacer on each wheel, and you only get one chance to pretension it (compress it) correctly, error means tearing it all back out and trying again so the manual and my instructions should help them get it right. I'm confident in the machine shop's ability to complete the job correctly and they're a great bunch of guys over there, but I'll be making sure they do it right of course.

I believe the special tool will arrive by Thursday or Friday so Friday is likely the day I'll bring this "driver's side" to the machine shop. If I'm lucky they'll have it done by Monday and I'll reassemble the driver's side. Once that is done I'll remove the passenger side and do the same thing. I should mention I'll be using synthetic grease for this step since synthetics tend to not break down like regular bearing grease might.

So some of you might be wondering why I'm not doing both sides at the same time. Well it's because I am not a machanic and I need a reference so that I can put this all back together the same way I took it off. By doing one side at a time I'll have something to look at. Note that the last time I worked on a car to this level I was about 16 years old. I'm now in my late 40's so I don't remember the difference between a control arm and a trailing arm. I'm just a guy that wants to say "hey, I did it all myself!".

I'll keep you posted on the progress as promised,
-Tony-

wbain5280 · #26 10-11-2006, 12:08 AM

Tony

I read your entry from 9/24 and it reminded me of a similar thing that happened to me. My thumb was cut while in auto shop class and it blead inside my nitrite glove. We must be very careful when working on our cars. Make sure you wear gogles too, your eyes are very precious. Brake fluid and battery acid are bad for ones eyes.

I really liked reading this thread and I'm glad your bringing your car back to specs.

red560SL · #27 10-13-2006, 06:03 PM

After careful inspection of the front calipers I decided to completely rebuild them. What I did was use an old set of pads and placed it between all the wheel cylinder pistons. I created an air hose out of an old brake line and put a ball valve between it. I attached this to the inlet of the brake line and presurrized the wheel cylinder which pushed out all the pistons just to the point of making it past the inner seal. I then removed the pads and gave it one last blast of air and one piston popped out. I then had to wiggle the other three to get them free. On the other side I found one of the calipers stuck so I made sure to extract that one first. There is no rust or pits in either the pistons or the cylinders so I'm good to go. I did clean things up a bit of course. In fact I have the calipers soaking in the parts cleaner now and will reassemble them tomorrow.

While the cylinders are soaking, I went back to work on the rear end of the car. As you know I have already removed the trailing arm from the car. Today my special tool to remove the slotted nut arrived. On the back of the flange you'll see the slotted nut. This nut is also bent over the grooves once you assemble it and have the right amount of free play. So what you have to do is unbend those little tabs and insert your special tool in the grooves. I used a screw driver to remove the outer seal and retaining ring. I then fired up the compressor and used my 1/2" impact and in a matter of a few seconds, the nut came right off! At this point the axle is still attached to the flange by means of pressure. What I did was take one of the old bushings from the trailing arm and used that as a punch tool (bottom right of pic). It's rubber and fits perfectly around the slotted shaft. It took about 5 blows and it all came apart (see pics).

I'm now going to take all this to the machine shop and see if they will pull the bearings, races and tensioning ring and press on all the new stuff. If they can do that for me I'll be ready to reassemble the rear driver's side.

At this point I can say the rear of the car has been pretty easy. As long as I can get the machinist to take care of the bearings I'll be happy with my progress. Today I asked the Mercedes dealer what they would charge to do nothing more than remove and replace my bearings and races. Keep in mind I have everything taken apart as the pics show. The dealer said it would be $350 for labor!!!

I'm starting to see the light at the end of the tunnel. Maybe another week or two of messing around and I'll be ready for a test drive.

Later,
-Tony-

red560SL · #28 10-18-2006, 10:23 PM

Yes I'm still here folks! I had a little delay or should I say setback? I noticed a problem with the rear subframe when I was cleaning it up for the new subrame bushings. In fact I had to ask for help here to verify what I found. The thread for this problem can be found here:

560SL Rear Subframe Question - Is this correct?

So far it doesn't seem there is any major problems and I can continue with my suspension rebuild, but as you'll find from the above post, I ended up removing the entire rear subframe and differential from the car. In the long run I think this will make it a bit easier to attach the trailing arms anyway.

So here's where I'm at. In my last post I brought my driver's side trailing arm with hub and bearings to the machine shop to have them press out the old races and bearings and install the new ones. They have completed this and the total cost was $60. They even set the end-play to .04 - .06 as specified by the manual. So that wasn't that hard now was it? Today I dropped off the passenger side to them to have that one done. So for a total of $120 for their labor and the parts cost of $93.54 + synthetic grease, I now have this all completed. I should be able to pick up the other trailing arm tomorrow afternoon and I'll attach them both to the subframe at the next chance I get.

Since I took out the entire subframe it also meant the differential had to be removed. This was actually quite easy to do and only requires three bolts and the disconnection of a sensor. The axles were already removed from the wheels so it was easy. And since the differential was removed, I'm also going to replace the CV boots. I ordered them today so I probably won't get them here until Monday. I also decided to purchase all the support bushings for the differential and they too are on order.

The front calipers are all done being glass bead blasted. This afternoon I took some time to place masking tape over the cylinders and openings of the callipers and tomorrow I'll paint them. Once dry I'll place them on the rotor and install the pads. This means the entire frontend will finally be completed!

With my little setback and the ordering of additional parts (hey don't tell the wife), it has set me behind. I might not be able to have the suspension completed for another two weeks. But I do know one thing, it should be awesome!

Tomorrow I'll take some additional pictures of the rear subframe, differential and trailing arms so you can see what a naked rear end of a 560SL looks like. It's scarry and my wife can't believe I did it. Obviously I'm not as fast as those guys on OverHaulin (love that show), but I bet I'm just as particular.

Later guys,
-Tony-

red560SL · #29 10-19-2006, 05:50 PM

Here are some pics of the entire rear with everything out. The spring on the right still has the spring compressor installed and the one on the left does not. You can tell from those pics that this compressor is probably a must as you have to compress it quite a bit to extract the spring. The rear end is sitting on a cheap transmission jack that I purchased at Harbor Frieght (about $50).

The other pic shows the driver's side trailing arm. What you'll notice is a can of silicone lubricant and a 5/8" all-thread going through both trailing arm bushings. I found installing these bushings are a real ***** with just a c-clamp and rubber mallet, but if you use some all-thread, a couple of washers, nuts and silicone lubricant it's a piece of cake. It didn't take a whole lot of torque for my bushings, but if it seems like a lot of torque when you do it you might want to cut a 2"x4" to fit between the arms just to be sure you don't break/stress something.

The front callipers are all painted and I'm about ready to reassemble them and place them on the rotors. I'm still waiting for parts before I can complete the rear end, but I expect them to be here the first of next week.

Later,
-Tony-