Pagoda SL Group
W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: Cees Klumper on November 02, 2008, 18:55:12
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So today I decided to go replace my rear wheel bearings; have been having an intermittent squeel from the right rear wheel, not influenced by the parking or disk brake, so I figured it would be the bearing. Went ahead and purchase bearing sets for all four wheels ("can't hurt, not expensive, originals are 40 years old").
I decided to go by the Haynes manual for the task. From the description it was a bit daunting and I considered dropping the car off at Van Dijk's, but went ahead anyway. Started with the right-rear, and disassembly of the driveshaft, brake disc, parking brake shoes, brake plate and old bearing all proved surprisingly easy. I installed the new bearing and oil seal and am getting ready to do the left side next.
Now for my question: the Haynes manual calls for a rather elaborate re-assembly procedure, requiring the removal of all three rear springs and rubber stops to enable the extreme upward movement of the axle tubes before re-fitting the right axle - this is to ensure, according to 'Haynes', that the circlip on the axle clears the sliding inner bearing o.k.
From the looks of 'my' circlip, and the ease with which the axle came out on dis-assembly, I would expect the axle to go back in quite easily, but I don't want to risk the problem that Haynes describes by not following their instructions. At the same time, removing those springs, particularly the center one, is a lot of work.
Has anybody re-assembled the right rear axle without removing the springs etc., just sliding it in and passing the circlip through the sliding bearing without a problem? Or had I better comply with the instructions (that would provide a good excuse to finally order and fit those new progressive-rate springs).
Any experiences/tips appreciated!
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Cees,
I'm not sure at what point they started to use these sliding sleeves with the circlips as you describe. I recall reading this same thing in the Haynes manual as weel. I've got a 230SL, though, and this rear axle does not use that circlip--thus I did not have to go through the routine you describe. Perhaps, Joe or Dan would be able to answer this better than I can.
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Cees, if you haven't already done so, you might want to read through Joe's "Rear Wheel Bearing Tour": http://index.php?topic=4487
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Hello Cees,
Yes, it sounds like a lot of extra work. I have never had issues, but I always put the car on stands so the diffential assembly is near horizontal. Position your jack stands out near the end of the axle tubes so the weight of the car holds the rear end horizontal. Add weight to the trunk if needed, and you should be fine.
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Thank you Waqas and Joe - I completely forgot there was a 'JA17 Tour' on this very subject. I will study it carefully before proceeding; also good to hear that the springs don't necessarily have to come out!
I will report back when I complete the job.
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From reading the 'tour' just now, I can already report two things:
- the bearing I found on the right-hand axle was the wrong kind (i.e. it is a 'regular' bearing, not the 'rolling cylindrical' one) - I imagine this would have put (a lot of) strain on that bearing, which is in fact the side of the car that produced the squeel
- there was no grease in the old bearing whatsoever!
It seems probable now that the bearing has started to spin in its housing (causing the squeel), which I will treat to some punchmarks and loctite when I put the new one in ...
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Cees,
You may want to consider drilling and tapping for Zerk grease nipples at the axle ends so that you can grease these rear bearings without having to disassemble everything. It's something that Dan Caron once mentioned. I did this with my 3.27 and it seems to work well. I plan to grease every 3000 miles along with the fronts and everything else.
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Cees .... I have also replaced right side axles without removing springs etc without issue (though a 230SL). I also do not worry about the ball verses barrel bearings. There was a period of years when MB deleted the barrel bearings and superseded it with the ball bearing. My cars both have ball bearing right side bearings and they have worked well for many miles.
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Thanks Jim. Actually SLS in Germany has an 'info' page on their website that has a drawing to explain the slightly changed angle at which the right rear axle moves during driving, and it shows that there is a slight difference; the text says that a roller-type bearing will tend to wear out quicker as a result, and they recommend the (more expensive) barrel/rolling-cylindrical-type. I did buy such a bearing already from Van Dijk, so will be installing that one just to be safe.
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Progress report is that, tonight, I put the new cylindrical bearing, new oil seals, gasket etc., in fact the whole right-hand side back into commission. Difficult part was to get the new bearing into its housing (which I had treated with a punch to ensure that the new bearing will not spin, following Joe's advice) - you can't really get to it as the whole assembly goes back into position. Getting the new inner oil seal into place was also a bit difficult. I raised the axle to horizontal position, but not beyond (i.e. I did not remove the springs) and the axle slid in just fine.
Also challenging was reconciling the need to have a lot of bearing grease packed into the same space where gasket shellac (to get a good seal on the oil seals) is also present, right next to the bearing housing, which I wanted to keep as clean (i.e. no grease) as possible to promote a solid fit so as to minimize the risk of it starting to spin. I think I managed though.
In retrospect I know now that the old right-side bearing was not installed properly (it was loose), was not greased and was not the recommended type, so I guess it was no wonder it failed.
Now onto the left hand side!
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I like to use Loctite stud and bearing fit on the bearings when installing them. I put it on the outer housing and on the inner shaft mount. It can really help a bearing seat and give a little insurance on a good fit.http://www.henkel-technical-services.co.uk/PDF/TDS/646TD.pdf For a looser fit and probably a great product for these bearings I like the Loctite bearing mount. I see it is now available in a stick form http://www.midwayautosupply.com/pm-12071-220-loctite-loctite-bearing-mount-stick-32-oz-39150.aspx These products require a clean surface. Loctite sells a primer but I have found starting fluid to work great. Definitely a light sanding with some emery cloth also helps the sealant. I have used that bearing mount on some very badly worn shafts with great success.
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This afternoon I finished the job by doing the left side. Toughest part, now that I have the right-side experience, turned out to be the thicker spring on the handbrake shoes; turns out it is far easier to install that one (the one closest to the handbrake cable connection) first, then the one on the opposite end, because it is a 'looser' spring.
Anyway, I went on my test drive and, low and behold, the squeel is still there (sigh) - so although replacing the bearings and seals was no doubt worthwhile as a preventive measure (likely I won't be having to replace those again in my lifetime), the culprit that started it all is still there! I suppose I should have done more diagnosing before I dove in. Next step will be to put the car on axle stands in the rear, starting it and putting it in gear, to see if I can pinpoint the noise. Most likely cause now I think is that something (exhaust clamps for instance) is rubbing against the driveshaft.
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Hey Cees, sorry to hear you are still squeelin. I must commend you, however, on going for it on the bearings and axles. I am afraid to death of mine - mainly because I will have to farm that job out (read $$$).
I wonder what your squeel sounds like exactly? As Waqas and others might recall, I chimed in once about my own high-pitcher that I was hearing. It sounds a lot like another squeel I sometimes hear when I tap the brakes on a downhill. High and whistly is how I'd describe it. But I hear this one mainly when I am underway and usually after a longish drive (and often on curves). Logical culprit is bearings but with your experience, I may just wait a little longer and see what you find!
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There is some interesting reading on the m-100 forum regarding replacing the right rear wheel bearing and ignoring the proper procedure of removing the springs and lifting the axle tube ends to their highest points. There is a big chance damage to the sliding joint could happen. I think the best info about this is from Chris Johnson in the third post from the top.
http://www.m-100.cc/forum/topic.asp?TOPIC_ID=1710
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James and Cees,
The timing of this is interesting. Having read this thread, I too had decided to replace my rear wheel bearings to try and tackle this sound. Now I'm not so sure anymore.
As James mentioned, I've heard the whistling sound from the rear (seems like the right side). It kicks in around 45-55mph and just stays like a constant whistle (kind of like a loud brake squeal). Tapping the brakes makes no difference, and neither does making turns. I'm sure it is not just wind, as it rings much louder when I go through a tunnel or an underpass. It's definitely a whistle and not a moaning sound.
So, might we all have a similar problem? Mine is definitely speed related, and I'm not sure how to debug this with the car stationary. (dyno-tester maybe?)
Can you describe the squeal in more detail?
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quote:
Originally posted by waqas
... I've heard the whistling sound from the rear (seems like the right side). It kicks in around 45-55mph and just stays like a constant whistle (kind of like a loud brake squeal). Tapping the brakes makes no difference, and neither does making turns. I'm sure it is not just wind, as it rings much louder when I go through a tunnel or an underpass. It's definitely a whistle and not a moaning sound.
Well, it is quite a sharp, 'tinny' squeel as if two metal objects are rubbing against each other, and it is rather loud. With the windows up, I can still hear it easily and often wonder what bystanders may think. With respect to the bearings, I thought it might be caused by a spinning bearing, but not a worn one (as that is being described as more of a rumble/groan, which this definitely is not: this is crisp, clear, high-pitch and 'on-the-surface, exposed-to-air').
It started about 3 years ago as an intermittent sound. Then more frequently, until now it's about always there, also at (very) low speeds, as in stop and go traffic. It seems to go away at higher speeds, but with the extra road and wind noise it's a bit hard to really tell. It changes with speed, so it is speed related and not engine RPM related. It does seem to come from the right rear but now that I have replaced and cleaned just about everything on and around the axles and break discs, it's hard to believe that it could be e.g. a brake pad. But I may go ahead and replace those now as well; for a few years I have had spare sets front and back sitting on the shelf, but since the current ones are still so new-looking, I have not replaced them. Then again, my sound is like Waqas': it does not go away when tapping either the brakes or applying the handbrake, which is why I thought it would have to be the bearing.
Maybe it is the break disc itself, rubbing against the dust shield, or against 'something' else. But before I put on the wheels yesterday, I spun them around and no noise.
What I am thinking besides the brake pads, as I mentioned in my previous post, is 'something' like an exhaust clamp (I did replace my exhaust system maybe a year before the sound started) rubbing against the driveshaft. Also because the sound barely changes when I swerve from side to side, or whether I am going over a speed bump or what have you, so it seems barely affected by the relative position of the wheels/axles.
The noise is so pronounced that I can't imagine not being able to pinpoint it after more diagnosing, and one of the steps is putting the car on axle stands (such that the wheels are in the same position as while driving), starting the car and putting it in drive, so that the rear wheels and the whole driveline can rotate. I won't be lying under the car then, incidentally. But I did apply this 'procedure' once before to find and correct an imbalance on the drive shaft of my Triumph Spitfire, 30 years ago and it worked perfectly then.
Replacing the bearings can be done by the average DIY'er (I know because I am one) - took about 11 hours in total, which included some lessons learned-time, and I figure that if the springs and shocks would have to come off, that would add maybe two hours. You would need a good spring compressor, but those can be had relatively cheap (I paid something like $60 for my set of three from Monroe, quite good quality) and those come in handy for a variety of things anyway. And it's like anything on our cars: tackling it yourself, provided you are careful and don't cause damage like to the sliding bearing, is very gratifying and you know the car that much better for future reference.
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I had the same annoying noise a few years ago. In my case it turned out to be a problem within the handbrake.
Gerard Wuisman
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quote:
Originally posted by gwuisman
I had the same annoying noise a few years ago. In my case it turned out to be a problem within the handbrake.
Gerard, do you remember the exact problem?
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Hello JG,
Interesting information. I always use the barrel/roller beaing on the right side. The roller/barrel bearing, besides being able to hinge, will handle higher loads. It is usually the ball bearing which fails on either side.
It appears that the higher torque V-8 differentials like the 3.27 are the only ones with the snap rings on the axle. Consider that the Mercedes 6.3 has 435 lbs. or torque! I will set up one of these V-8 differentials on the work bench and see exactly when the snap ring engages the slot in the sliding sleeve.
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Hello Cees,
The emergency brake assemblies on the disc brake cars can often be the most troublesome part of the bearing change. I have some information and photos here which may help you next time. I will add this information to the tour also.
Here is a photo all the emergency brake parts;
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This photo shows a backing plate with the parts installed. The adjuster can be installed in either direction so take note which way it is pointed for re-assembly otherwise adjustment may be backwards but will work fine.
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Two special tools will make the job quite a bit easier. One can easily be home made, the other is an inexpensive spring tool. Grind a round screwdriver shaft or similar for the home made tool.
Download Attachment: (http://images/icon_paperclip.gif) special tools.jpg (http://www.sl113.org/forums/uploaded/ja17/2008111005820_special%20tools.jpg)
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Use the home made tool to release the retainer springs first. Push in then do a quarter twist to release. The retainer spring hooks through the hole in the backing plate see photo of the back view.
Download Attachment: (http://images/icon_paperclip.gif) removal of retaining springs.jpg (http://www.sl113.org/forums/uploaded/ja17/2008111005937_removal%20of%20retaining%20springs.jpg)
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Download Attachment: (http://images/icon_paperclip.gif) back view.JPG (http://www.sl113.org/forums/uploaded/ja17/200811101234_back%20view.JPG)
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After both retainer springs are removed use a large screwdriver to pry the top brake shoe far enough to remove the adjuster. this will loosen up the entire assembly enough so that you can remove both upper and lower return springs with the spring tool.
Download Attachment: (http://images/icon_paperclip.gif) remove adjuster.jpg (http://www.sl113.org/forums/uploaded/ja17/20081110146_remove%20adjuster.jpg)
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Both emergency brake tools can now be remved. Next remove the cam assembly by pushing the connecting pin out.
Download Attachment: (http://images/icon_paperclip.gif) removal of cam unit.jpg (http://www.sl113.org/forums/uploaded/ja17/200811101551_removal%20of%20cam%20unit.jpg)
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There is a special "C" clip which must be removed before the emergency brake cable can be dis-connected from the backing plate.
Download Attachment: (http://images/icon_paperclip.gif) removal of emergency brake cable.JPG (http://www.sl113.org/forums/uploaded/ja17/20081110179_removal%20of%20emergency%20brake%20cable.JPG)
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Continue the axle removal by unfastening the 13mm nuts around the axle.
My re-installation of the emergency brake assembly is the reverse order of above. I prefere to deviate from the factory assembly sequence in that I install the brake adjuster and top return spring last instead of first.
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Cees ... After some research, I believe the correct name for the bearing is a spherical bearing. The purpose is to allow the axle center line to move without putting stress on the bearing. See the picture below.
When I looked up the baring price several years ago, it was about $500; I just checked today and it has dropped to about $130 so price is not a good reason to not use the correct bearing.
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Jim,
Do you have the part number for this spherical bearing? I have the [supposedly] correct bearing for my 1966 coupe from Mercedes (Part number 008 981 4225) and it's the ball bearing type. They are the same for both left and right sides. I was told the spherical bearing is only used on the rear axles of the V-8 cars.
Are the spherical bearings also used for the original axles of our straight-sixes? (same for both left and right sides?)
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Cees/Jim--this bearing is a self-aligning roller bearing. It's manufactured by FAG and the number is 20208. I just purchased and received one from SLS for about $95.00 or so.
George Des
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I also paid about EUR 80 or so for my spherical (thanks Jim!) bearing. As I posted before in this thread, the one on the right-hand side axle was a regular 'straight' ball-bearing type. It had more play in it that I would expect, but as it turned out was not the cause of the squeel problem, so maybe it was still ok. I believe it was the oriiginal bearing. No grease anywhere in sight, so I am still glad that I replaced it with the new spherical one.
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Wagas .... The number I have for the right rear bearing is 000 981 05 06.
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Wagas .... The number I have for the right rear bearing is 000 981 05 06.
Jim, thanks for the part number. It corresponds with the Technical Data Manual (Issued October 1969). I always forget it has part numbers for certain items.
To summarize my understanding: the right rear bearing is the Cylindrical Roller bearing 000 981 05 06 and the left rear bearing is the regular ball bearing 008 981 42 25.
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Wagas,
The bearing number you are using is the MB number. The 20208 number is the standard bearing number for this self-aligning roller bearing. If you order the MB number, you will get either a FAG or SKF 20208 bearing.
George Des
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Update - this thread got started as a result of me replacing the rear wheel bearings in order to fix a squeel that I thought was coming from the right rear wheel. Replacing the bearings did not remediate the problem though.
Tonight I looked further. I pushed the car backwards and forwards to see if I could locate the source of the squeel. It turned out to be coming from the right front (rather than the right rear) wheel. I took off the wheel, and noticed that the steel brake pad retainer clip was not in exactly vertical. I straightened it, put the wheel back on, and went for a test-drive. No squeel. It's probably to early to pop the champagne, but I have high hopes!
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There is some interesting reading on the m-100 forum regarding replacing the right rear wheel bearing and ignoring the proper procedure of removing the springs
http://www.m-100.cc/forum/topic.asp?TOPIC_ID=1710
M-100 cars (600 Limos and 300SEL 6.3's) didn't have springs, these cars all came equippped with air suspension.
The original application of the self aligning bearing was for the right side of the 300 series cars because of the variable ride height. I don't think any 113 cars came fitted withe these from the factory, but the ball bearings failed frequently, so the reccomended replacement on the right side was the more expensive bearing from the air suspension cars. I believe that all V/8 cars with either air or coil springs had the barrel roller bearings on the right.
A whistling or ringing sound could be a pinion bearing or improperly set pinion tension. When an axle bearing fails the sound usually is a low frequency (growl) because of the slower speed the axle shaft turns at.
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I have a 1970 280sl, my rear axle is in pieces and I plan to start reassembly shortly. I read extensively before dismantling it and this included the M100 threads. These do state that you should insert the right half-axle with both axle tubes pushed up as high as possible so that the axle clips into a circlip in the sliding sleeve to ensure that the sliding sleeve moves with the axle shaft. My sliding sleeve assembly does not have a circlip to clip the axle into nor is there any place to put one so I assume that it is not missing. It was not in the axle tube when I took it apart. My right rear axle did have the correct self aligning roller bearing on it. The MERCEDES-BENZ type 250sl-280sl Catalog B 1968 that came with my car does not show any circlip on page 86 where the rear axle is displayed. The right and left axle tubes differ in that the right axle tube has a ridge about 4 inches outside the splines to stop the axle moving too far through the sliding sleeve.
It seems that these circlips were not on all the rear ends. This would imply that you do not need to elevate the rear axle tubes when reassembling these rear ends. Perhaps these circlips were only found on the more heavy duty 3.27 rear ends?
What has been the experience from anyone out there who has recently rebuilt their rear end?
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There were no circlips when I installed my 3.27.