Check those front wheel bearings - Page 3 - PeachParts Mercedes-Benz Forum

jay_bob · #31 12-15-2014, 07:12 PM

You can hear the roller bearings moving around in there in that video. Mine sounded like I was driving on gravel when I spun it after it totally failed.

I did get the bearings replaced last Friday afternoon. I used the entire 150 g tube of grease between the two bearings. Bearing drift set works great to not only set the races, but if you flip the disk over so that it is flat, it is perfect for setting the grease seal.

Bearing kit also contains all new caliper bolts, and the little hex bolt that secures the rotor. It does not include the clamping nut nor the set screw for the clamping nut. The left side clamping nut showed scoring and damage after the failure so I replaced the clamping nuts. I had to reuse the old set screws as they are a separate part from the clamping nut.

I did the dial indicator thing, got the clamping nuts set right, put the grease cups on, and got the car back on its wheels for the first time in a week.

Be sure to keep a clean work area when packing the bearings and be sure to only have clean gloves on when handling the bearings. I probably went through half a dozen pairs of disposable gloves as I was packing and installing the bearings and hubs. Sorry no pictures, I was too focused on keeping things clean and doing my steps in order that I forgot to pick up the camera.

vstech · #32 12-15-2014, 11:37 PM

Quote:

Originally Posted by jay_bob

You can hear the roller bearings moving around in there in that video. Mine sounded like I was driving on gravel when I spun it after it totally failed.

I did get the bearings replaced last Friday afternoon. I used the entire 150 g tube of grease between the two bearings. Bearing drift set works great to not only set the races, but if you flip the disk over so that it is flat, it is perfect for setting the grease seal.

Bearing kit also contains all new caliper bolts, and the little hex bolt that secures the rotor. It does not include the clamping nut nor the set screw for the clamping nut. The left side clamping nut showed scoring and damage after the failure so I replaced the clamping nuts. I had to reuse the old set screws as they are a separate part from the clamping nut.

I did the dial indicator thing, got the clamping nuts set right, put the grease cups on, and got the car back on its wheels for the first time in a week.

Be sure to keep a clean work area when packing the bearings and be sure to only have clean gloves on when handling the bearings. I probably went through half a dozen pairs of disposable gloves as I was packing and installing the bearings and hubs. Sorry no pictures, I was too focused on keeping things clean and doing my steps in order that I forgot to pick up the camera.

No pics? Ugh, Jaaayyyy... Don't you know you are supposed to have a photographer with you while you work? Sheesh!

How accurate did my old school twist and lock method of bearing setting get?

jay_bob · #33 12-16-2014, 09:13 AM

Pretty close, I just had to tweak it a little and dialed them right in.

Cranked the clamping nuts down snug (so that it was difficult to turn the hub), backed off 1/4 turn (I could feel the tension release), set up the dial indicator, went through about a half dozen iterations of push/pull/adjust clamping nut until it was just right. Hardest part is keeping the clamping nut in position while tightening the set screw. It is pretty sensitive, fraction of a rotation throws it off. I had to go through the process several times because of disturbing the clamping nut while tightening the set screw. Finally got it after a couple of tries.

Tip: set the dial indicator up so that it is reading in the center of its travel. It is most accurate there. Remember you are looking for a differential of 0.01 to 0.02 mm, which is very small. If you have an inch gauge, you are looking at slightly less than 0.001 inch deflection for 0.02 mm. About 3/4 of one division on the outer dial. 0.00079 inch = 0.02 mm to be precise.

Another tip: save and clean up the old dust covers, they work great as a drift to drive on the new dust covers.

dieselbenz1 · #34 12-16-2014, 09:35 AM

Magnetic base mount of dial indicator on hub or on rotor? The distance will affect accuracy and have seem both presented in DIY just wondering where you placed your.base?

jay_bob · #35 12-16-2014, 09:49 AM

While installing, and you have the dust cover off, set the magnetic base on the hub, pointer on the center of the spindle. There is a convenient little divot in the center of the spindle to accept the pointer from the dial gauge. I did this before installing the rotor.

If you are trying to check play after installing the dust cover, like as part of a maintenance check, the objective is to see the difference between the parts that rotate and the parts that don't.

In that case remove your caliper and rotor, hang the (edit: caliper) up out of the way, and go the other direction. Set the base on the hub, and place the pointer on one of the caliper ears. The caliper ears are cast with the spindle assembly, so that is the same point of reference as the end of the spindle with respect to the hub. This saves you from having to open the dust cover.

Just remember to clean the caliper/rotor bolts and put blue loctite on before reassembly. The FSM calls for replacement if removed, but I don't think these are stretch to yield bolts, they are concerned about ensuring there is thread locker present.

Zulfiqar · #36 12-16-2014, 03:04 PM

Is it just me noticing - most bearing failures occur in lower temperature. Worn out grease perhaps? or wrong grease -

I have removed MB green grease from my W124 that looked shiny but was stiff like candle wax and the bearing rollers had a black gooey oil only (didnt resemble any grease I know of).

jay_bob · #37 12-16-2014, 03:36 PM

Did the black stuff smell burnt? That was how my right side was, in the beginning stages of failure. Luckily I caught that one in time, there was no hub or spindle damage yet.

Cold weather definitely changes the viscosity, the grease can't flow as well when it's cold.

sokoloff · #38 12-17-2014, 12:12 PM

Nice write up - thanks.

The bearings on my 210 are original and unmolested. Been thinking about doing them for a couple of years. I've done the bearings on my 240D and my ponton, but it's been years. You interested in doing another one while it's fresh in your mind?

When you say you used the entire 150g tube of grease, is that between the two wheels or all on one wheel? I'm assuming it was for the entire front end. Do you recall what the spec is for the recommended amount of grease? For most cars I seem to recall it being 65 - 70 g per side.

Zulfiqar · #39 12-17-2014, 01:22 PM

Quote:

Originally Posted by jay_bob

Did the black stuff smell burnt? That was how my right side was, in the beginning stages of failure. Luckily I caught that one in time, there was no hub or spindle damage yet.

Cold weather definitely changes the viscosity, the grease can't flow as well when it's cold.

not exactly a burnt smell but a rotten smell - it was not super slick either and had coated the rollers in a nice shade of grayish purple (looked like blueing - but cleaned out with acetone) - no sparklies in the grease either.

packed it up and set it by hand - I have a different technique, I once advance by hand and note where it is, then advance with a screwdriver in the pinch bolt opening and note where it stops - I place it a bit before the center point of both. Never had issues and the wheel is not sloppy.

wheels run really cool too. For weight I have an old lab scales - 60 or something grams of grease in a baggie along with bearings in it, work it in, remove bearings and install, install grease seal, make cone out of baggie and push grease into hub like a baker does icing on a cake.

Before I had the scales I would eyeball the grease cartridge and spoon out the required height of grease from it.

I do own a dial gauge - but its usually missing when I need it (borrowed or hidden somewhere)

jay_bob · #40 12-17-2014, 02:07 PM

Quote:

Originally Posted by sokoloff

Nice write up - thanks.

The bearings on my 210 are original and unmolested. Been thinking about doing them for a couple of years. I've done the bearings on my 240D and my ponton, but it's been years. You interested in doing another one while it's fresh in your mind?

When you say you used the entire 150g tube of grease, is that between the two wheels or all on one wheel? I'm assuming it was for the entire front end. Do you recall what the spec is for the recommended amount of grease? For most cars I seem to recall it being 65 - 70 g per side.

Yes the spec of 65-70 g per side is correct.

70 x 2 is 140. I figure you are going to lose about 10 g on your hands while trying to pack the bearings. Also not every bit comes out of the tube.

jay_bob · #41 12-17-2014, 02:28 PM

Quote:

Originally Posted by Zulfiqar

not exactly a burnt smell but a rotten smell - it was not super slick either and had coated the rollers in a nice shade of grayish purple (looked like blueing - but cleaned out with acetone) - no sparklies in the grease either.

That was how my right bearing was. Definitely discolored, funky smell (but not near as bad as the left - that stuff smelled like the grill after a long shift at McDonalds), residue cleaned off the spindle with brake cleaner on a paper towel. I did not reuse the bearing, I went ahead and bought 2 sets.

Quote:

Originally Posted by Zulfiqar

packed it up and set it by hand - I have a different technique, I once advance by hand and note where it is, then advance with a screwdriver in the pinch bolt opening and note where it stops - I place it a bit before the center point of both. Never had issues and the wheel is not sloppy.

I am a newbie at this, I did not want to fail so I used the dial gauge method. Vstech is old school and he can set them by feel. I am not that experienced and I was doing it by myself at home.

Quote:

Originally Posted by Zulfiqar

wheels run really cool too. For weight I have an old lab scales - 60 or something grams of grease in a baggie along with bearings in it, work it in, remove bearings and install, install grease seal, make cone out of baggie and push grease into hub like a baker does icing on a cake.

Before I had the scales I would eyeball the grease cartridge and spoon out the required height of grease from it.

I do own a dial gauge - but its usually missing when I need it (borrowed or hidden somewhere)

I did the similar trick, after smearing the spindle with a thick coat, I mounted the hub, but before I installed the outer bearing, I took the tube and shot as much as it would stand into the hub/spindle space. That used up about 80% of the tube once I got both hubs mounted. The last bit I put into the dust cover, the FSM for the 124 (the 210 bearing design looks to be the same as the 124) calls for 15 g of grease in the cups.

I also made sure to put some extra grease on the outward face of the outer bearing where it rubs against the clamp nut. I did this after setting the bearing play so that it would not affect the reading.

Zulfiqar · #42 12-17-2014, 05:52 PM

yes the 210 hub and bearings are similar to W124 - same procedure applies, one thing to make sure is that you dont overfill the grease, it can stall in the hub and can also push out from the grease seal as the wheel spins.

overfilled can also create problems when hammering on the dust cover - too much grease can become hydraulic and blow out the grease seal.

jay_bob · #43 12-17-2014, 06:38 PM

Good point, that is why they specify the quantities (65-70 g in the bearings/hub, 15 g in the cup).

That is also why the size of the tube is 150 g, it pretty much guarantees you can't under/overfill it, as long as you are balanced in the distribution between the two sides and use it all, except for the waste on your hands and what's left behind in the tube.

Those clever engineers...

NickCox · #44 02-06-2015, 11:56 AM

I think the spec is 60 g in hub bearings and 15 g in dust cap...

Guessing like most things there is a little slack on the spec.

jay_bob · #45 01-02-2019, 05:13 AM

Just had to replace the bearings on my 2008 E320. Very similar setup to the W124 and W210 (and I’m sure many others).

There is one critical difference between the W211 and the older models however.

On the W124 and W210 there are a series of ridges cast into the outside face of the inner end of the hub. These pass by an inductive sensor in the housing, set perpendicular to the spindle, that counts the ridges to determine wheel speed. On the W124 this is just used for ABS but on the W210 it goes into the computer and used for many things. The sensor is a simple inductive coil that checks for the disturbance of the magnetic field as the ridges go by.

On the W211 they changed the inner grease seal to include a circular ring of magnets embedded in the outer surface, and the inner end of the hub is smooth on the outside. The sensor is now a Hall effect type, that is sitting in the face of the steering knuckle assembly, parallel to the spindle.

When setting the grease seal, it must be perfectly flush with the face of the hub and no deeper. I inadvertently set the first one about 1 mm too deep and it caused ABS/ESP errors because the sensor could not reliably detect the magnets. I put the car on Xentry and drove up and down my street and it was just enough gap to make the data intermittently not OK. $14 and a new seal later and everything is fine. Luckily I did them one at a time so I was able to learn and do the second one correctly the first time.