|
ewalberg
Expert
Date registered: Apr 2006
Location: Past: San Francisco. Present: Germany
Vehicle(s): 2000 g500
Posts: 1887
| wheel bearing job... some questions for the experienced
so i've finally taken the plunge into my axle and now i have some questinos.
The left side is almost completely apart, but i can't get the race for the main bearing off the hub. i've copied a a picture from hipine's clubgwagen article showing which race wont budge
Also, i've copied in another picture showing the seals which bolt to the back of the swivel housing. I know the chamfer on the seal is suposed to face the ball so they match surfaces. What about that outer metal plate? It's also got a chamfer on it. On mine the chamfer is facing away as opposed to towards the ball.
If i've gotten this far should i re-grease my CV's? i'm tempted not since it's just one more thing to do.
As a side note neither the inner or outer lock nut were difficult to move. But were kep completely clean... looks like there was some gunk around the rim of the dust cap which reminded me of the gunk they seal doors with.
Thanks ahead of time.
 (main bearing.JPG)
 (swivel seals.JPG)
Attachments
----------------
 main bearing.JPG (8KB - 9 downloads)
swivel seals.JPG (8KB - 12 downloads)
|
|
| |
|
-UG-
Extreme Veteran
Date registered: Jun 2006
Location: Finland
Vehicle(s): GD300, S350 CDI
Posts: 446
| RE: wheel bearing job... some questions for the experienced
It is practically impossible to remove without braking it. I normally break the retaining mesh to expose the inner ring of the bearing. Then I just take a small grinder and grind one section of the ring until it brakes. Simple and fast, but you need to be careful not to grind the hub itself. Some scratches won't hurt, but it can be done without even touching the hub.
-UG- |
|
| |
|
dai
Expert
Date registered: Apr 2006
Location: Oregon USA
Vehicle(s): 300GD 300TD BMW R100RS Landini 80F
Posts: 2110
| Re: wheel bearing job... some questions for the experienced
There is a knive edge bearing puller that can easily remove the bearing from that stubshaft. I can try to post a photo of the thing later this evening if you need it. They can be rented from a tool rental place. A machine shop can have that off in less than 5 minutes if you have access to one close. A small press is the ticket for pulling thoses bearings off and seating the new ones. It is great you are tackling the job yourself. It demystifies the front end.
I think the metal ring orientation you found is correct.
The sealant on the dust cap is a good idea and you could use a little hylomar there.
With the miles on your truck you probably don't need to repack the C/V's but that's my opinion.
-Dai |
|
| |
|
AlanMcR
Expert
Date registered: Apr 2006
Location: US, CA, Los Altos
Vehicle(s): G300DT E300DT 230SL
Posts: 3500
| RE: wheel bearing job... some questions for the experienced
I tried a knife edge puller and only wound up wrecking the puller. That ring was practically welded to the hub. The solution was, as -UG- stated, to grind a slot into the ring and then snap it. I used a Dremel with a small fiber reinforced grit wheel. Cut down until you can't avoid cutting into the hub, then take a cold chisel and hammer it into the slot. the ring will break with a very satisfying 'ping'. Then, off to the next roadblock :-).
Edited by AlanMcR 9/18/2006 12:31 PM
|
|
| |
|
-UG-
Extreme Veteran
Date registered: Jun 2006
Location: Finland
Vehicle(s): GD300, S350 CDI
Posts: 446
| RE: wheel bearing job... some questions for the experienced
That's right. I experimented with all kinds of pullers too at the first time. I even welded one to the bearing ring to avoid slipping of the puller. Nothing but broken pullers. We even had a hydraulic press in our garage at that time (it's sold now). I am wondering how it could have helped the removal of the old bearing though? I was handy when pressing the new bearing in place, but removing?
The only quaranteed technique is that disk grinder.
-UG-
Edited by -UG- 9/18/2006 2:17 PM
|
|
| |
|
ewalberg
Expert
Date registered: Apr 2006
Location: Past: San Francisco. Present: Germany
Vehicle(s): 2000 g500
Posts: 1887
| RE: wheel bearing job... some questions for the experienced
I've got an angle grinder i use on wood stuff and it came with a ceramic disk for metal so i'll hit it with that, it should go pretty quick. Thanks for the tip.
Also, damned ABS sensor broke after getting it 75% out. I don't know how the hell anyone could get them out without damage. Hope wiring in the new one isn't a pain in the butt (never mind the cost)... we'll see...
|
|
| |
|
AlanMcR
Expert
Date registered: Apr 2006
Location: US, CA, Los Altos
Vehicle(s): G300DT E300DT 230SL
Posts: 3500
| RE: wheel bearing job... some questions for the experienced
I broke an ABS sensor too. Try chilling the next one (liquid nitrogen is probably too cold) and then pushing it out gently.
Wiring up the new sensor involves silicone lube and patience while pushing the connectors through the rubber discs. It probably wouldn't hurt to make the channels a bit larger, but it can be done w/o modification. |
|
| |
|
460332
Date registered: Apr 2006
Location: Europe
Vehicle(s):
| Re: wheel bearing job... some questions for the experienced
I grinded a groove half way round the race, carefully, while measuring the depth, then I used a chisel that didn't reached the bottom of the groove to split the race along the groove. I freezed the hub and heated the race while assembling, make the race easily fit in place. Max 200 degee C on the race.
Metal chamfer should point outwards, gives more support to the plastic seal
Ensure that you get the lock nuts and lock washer right!
Fill grease around lock nuts. MB reccommends re-greasing CV-links every 100.000km on GW, use special moly-grease for CV-links. Use wheelbearing grease at bearings and 2 tubes of multipurpose grease for each knucklehead (800 grams, as MB says ).
Edited by 460332 9/18/2006 7:25 PM
|
|
| |
|
ewalberg
Expert
Date registered: Apr 2006
Location: Past: San Francisco. Present: Germany
Vehicle(s): 2000 g500
Posts: 1887
| RE: wheel bearing job... some questions for the experienced
were you able to tap them out from the inside? I was pulling mine when it broke figuring once i pulled the king pins it'd be a real pain to try and work on that. Mine came with NTN Japan king pin bearings and German wheel bearings. |
|
| |
|
dai
Expert
Date registered: Apr 2006
Location: Oregon USA
Vehicle(s): 300GD 300TD BMW R100RS Landini 80F
Posts: 2110
| Re: wheel bearing job... some questions for the experienced
I had no issues using the pullers. Harald's or mine. Even Tom's very roached ones were persuaded. Sounds like we were lucky.
460332's comment about freezing the hub and heating the bearing is excellent. I used this technique and it just about dropped into place. An oven works well or a heatgun.
I think NTN bearings are excellent. German FAG and Euro SKF's are super too.
I used Redline grease in everything. It is a C/V compatible grease and the logic is that if the C/V boot breaks it will be riding in a grease that will not be an issue. I have heard of folks rebuilding these things and not running a boot. I am also hoping the grease will buy a little longer life to the bearings by possibly running cooler. So far all is well.
-Dai |
|
| |
|
AlanMcR
Expert
Date registered: Apr 2006
Location: US, CA, Los Altos
Vehicle(s): G300DT E300DT 230SL
Posts: 3500
| RE: wheel bearing job... some questions for the experienced
I broke the first one pulling. For the second one, I tapped from the inside. First you will want to scrape the any crud off of the sensor in the area that will have to slide through the hole. Then, a little lube won't hurt. |
|
| |
|
ewalberg
Expert
Date registered: Apr 2006
Location: Past: San Francisco. Present: Germany
Vehicle(s): 2000 g500
Posts: 1887
| how much wheel bearing grease?
so i'm ready to put this stuff back together but can't find any info on how much wheel bearing grease to put in there. I've packed the races themselves, and some in the pocket between the races but should i pretty much pack it full? I think maybe not?
and is there a torque spec for the (1) king pin bolts, (2) bolts that hold the seal to the swivel ball, (3) brake caliper bolts, and (4) has any consensus ever been reached on how to ultimately tighten these darned bearings?
Oh, and for my 6th questions, some of these bolts come with what looks like blue threadlocker... can (or should) i buy the "blue" threadlocker from loctite to make sure things stay put?
Thanks a bunch ahead of time.
Erik
Edited by ewalberg 9/21/2006 5:07 AM
|
|
| |
|
dai
Expert
Date registered: Apr 2006
Location: Oregon USA
Vehicle(s): 300GD 300TD BMW R100RS Landini 80F
Posts: 2110
| Re: wheel bearing job... some questions for the experienced
Eric,
Sounds like you have the right amount of grease. Packed full is not right.
I will look up the torque specs. I first set up the bearings by the freeplay spec of 1 thousandths of an inch of freeplay with a dial indicator. You can feel that movement when you grab the wheel top to bottom. I ran it that way for a very short time and then took the freeplay out to 0 freeplay. I did this by marking the inner locknut and changing its position slightlly until I got slight preload. The tricky thing about this is that the outer locknut loads the inner one and it is easy to overload the setting. I have a lot of miles on it and things are happy and there is no detectable play when the twist the wheel check is done.
I used anti seize on the bolts except the brake caliper bolts. There I used threadlocker. Bolts that have a lockwasher greneraly stay where they are tightened if the lockwasher is in good shape.
-Dai |
|
| |
|
dai
Expert
Date registered: Apr 2006
Location: Oregon USA
Vehicle(s): 300GD 300TD BMW R100RS Landini 80F
Posts: 2110
| Re: wheel bearing job... some questions for the experienced
The above comments presume that the bearings have already been preloaded as per the manual.
Kingpin top 110-125NM or 80 Foot pounds
Small bolts holding the gasket 20-25 NM
M 14 bolt at the caliper 190-220nm 140 ftlbs
M 16 250- 280NM 150+ ftlbs
The book spec on the bearing freeplay is 0.02-0.04mm FYI
I think 0 is a better number. They will live longer.
THESE SPECS ARE FOR THE 460 SERIES
Your specs may vary.
-Dai
Edited by dai 9/21/2006 10:34 AM
|
|
| |
|
fourbyfourclub
Extreme Veteran
Date registered: Apr 2006
Location: New Jersey, USA
Vehicle(s): 300G
Posts: 302
| RE: wheel bearing job... some questions for the experienced
Always use Blue Loctite for lower and upper king pin bolts, there are no lock washers on a W463 .
Free play on an adjusted bearing should be 0.1-0.3mm, remember the most important rule- loose bearing much better that tight bearing.
|
|
| |
|
ewalberg
Expert
Date registered: Apr 2006
Location: Past: San Francisco. Present: Germany
Vehicle(s): 2000 g500
Posts: 1887
| RE: wheel bearing job... some questions for the experienced
4x4club... do you know a procedure for tightening them? I've heard something like, tighten inner nut to high spec to seat everything, then back of 1/4 turn, then tighte lock nut to some torque. I've also heard after taking the inner nut to spec, back off and finger tighten, then torque locking nut.
i was surprised to find neither were hard to loosen on my truck on pulling them apart. The threads on the CV axle/shaft are still in very good condition so that makes me happy. |
|
| |
|
fourbyfourclub
Extreme Veteran
Date registered: Apr 2006
Location: New Jersey, USA
Vehicle(s): 300G
Posts: 302
| RE: wheel bearing job... some questions for the experienced
Hello Erik!
I can send you some guide for front bearing adjustment. Put you calipers and rotors first (without pads) to make sure you have equal gap between brake rotors and caliper slot.
Give me one day and I'll email you some sort of adjustment procedure.
I surprise you do not have installation manual with your bearing kit. We always send 7 pages installation manual with all our bearing kits.
|
|
| |
|
dai
Expert
Date registered: Apr 2006
Location: Oregon USA
Vehicle(s): 300GD 300TD BMW R100RS Landini 80F
Posts: 2110
| RE: wheel bearing job... some questions for the experienced
ewalberg - 9/21/2006 5:37 PM
4x4club... do you know a procedure for tightening them? I've heard something like, tighten inner nut to high spec to seat everything, then back of 1/4 turn, then tighte lock nut to some torque. I've also heard after taking the inner nut to spec, back off and finger tighten, then torque locking nut.
i was surprised to find neither were hard to loosen on my truck on pulling them apart. The threads on the CV axle/shaft are still in very good condition so that makes me happy.
Backing off the inner nut after the high torque preload bearing seating action to a loose state and then close to finger tight will put things in the target area. The problem is that the locknut is at a high final torque that will press against the inner nut threads and shove it against the bearing. In my opinion and I think a few others, you want slight preload on those bearings but not much. When I set up the bearings at Harald's without a dial indicator I had a lot of preload as result. Personally I like following the procedure in the shop manual and I used a dial indicator with a magnetic base. I got it close to the thin .02mm freeplay with the outer locknut torqued to spec. It takes trial and error of the inner nut to achieve this. I could find no magic back it off 1/4 turn etc. to get there. In fact very small amounts of movement homed in on the setting. I used the edge of the keyway cut in the spindle as a reference and marked the inner nut so I could see it's orientation. I tightened the outer nut and measured it. Too loose;I backed off on the outer locknut, tightened the inner nut slightly and retightened the outer nut. To hit it at .02mm is shaving hairs. One thousandth of an inch roughly.
So.. after setting them up by the book there is detectable play when you have a wheel mounted and you do the loose test. After reading Dave G's tech article and a number of other thoughtful posts by Dave and others who pretty much made an excellent case for no movement or 0 preload I returned to the job and tightened them ever so slightly to achieve just that. I also kept the final torque on the outer nut to a rational 130 ft lbs or so to avoid distortion of the threads on the spindle. There is also the locking tab as added protection. I also intend to check them over time.
I will say that in other MB chassis wheel bearings have no play. If you lift a 123 chassis and check the rears there is no movement when you do the test. None. If there is it's bearing time. I have a pair of these with an excess of 370,000 miles and still ticking. Having said that I am doing a pair of rears on another because one just died at 240,000. Some of the best engineering ever. I agree with the camp that says no movement or slight preload. I went out and got a dial indicator for the job because I wanted to do it precisely. The tool was easy to justify, I saved close to $1000 on labor. I am sure I still owe Harald a lot of beer for his great instruction on the first side. The parts cost a lot and the job is pretty time consuming. I want to wait another 100,000 or so before doing it again on the G as much as I enjoyed working on it.
-Dai
Edited by dai 9/21/2006 10:47 PM
|
|
| |
|
ewalberg
Expert
Date registered: Apr 2006
Location: Past: San Francisco. Present: Germany
Vehicle(s): 2000 g500
Posts: 1887
| RE: wheel bearing job... some questions for the experienced
4x4club, i can take a fax at...
attn: erik walberg
(650) 813-1857
Dai, i can get access to a dial indicator but i'm having trouble imagining a flat enough surface to place the base on? somehwere on the knuckle and then put the ball tip of the indicator on the outside edge of the hub?
I never was able to detect any play in my bearings so i'm on board with no play... overtorque is bad bad too.
I don't know if hipine is lurking on this thread, but on my truck i made the observation that the seal for the inner bearing should not be pushed past the face. I first tapped the seal until it touched the race until the outer lip touched the bearing, but then i noticed the actual rubber part of the seal was also against the race and not sitting naturally... which didn't seem right by memory. Looking at the witness lines on the CV shaft it looks pretty clear that the seal wasn't against the bearing, but rather much more likely that the seal stopped at the face... and jived more with my memory. I think the bearings are different on the 460 and 463, so this may be one aspect of the difference. On other thing i would recommend is loosening all the bolts for the king pins before removing the knuckle and i never pulled the steering link off the lower arm.
If people are getting discouraged from doing this job by themselves ready my questions, it's actually not that bad at all. Slow for me, but not too bad. I had already seen it done once, but all things considered it seems more complicated when i watched it done than when doing it. In retrospect, it seems that many shops do it badly because the axle is too similar to other vehicles so the mechanics think they know what they're doing... for example on some other trucks, i learned that the preload on the bearins is set by spacers... so you can just crank down on the lock nuts... ooops!
|
|
| |
|
dai
Expert
Date registered: Apr 2006
Location: Oregon USA
Vehicle(s): 300GD 300TD BMW R100RS Landini 80F
Posts: 2110
| Re: wheel bearing job... some questions for the experienced
Stick the base against the mount for the brake caliper. In the book they bolt a flat piece of metal to it to support the base to it but it wasn't needed for my mag base.
Flush with the edge is correct for the seal.
-Dai |
|
| |
