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How to grease the supercharger bearings if they're closed?
Hello everybody.
I'm doing some "start of the relationship mainteneance work" on my e55. I read quite a few topics about it but didn't find an answer
Just removed the supercharger. Did an oil change and wanted to grease the back bearings. The problem is I see those are the "RS" type bearings so they are "closed" with a steel dust cover. How can I grease them then?
Don't know if it makes any difference but it's the updated "0580" version of the supercharger.
Supercharger must come apart to grease bearings. Real easy to do since it already is off the car.
Rotors will need to slide out in order to see them and grease them up.
Hmmmmm.... thats what I thought for a minute after taking of the last back cover but... the problem is I made my shopping before doing the work and (according to Mercedes EPC) I did order only one piece of the gasket number 3 from pic below.
So... there is no way I can get more gaskets ATM as I need to assemble the supercharger today (need to free the workshop floor before monday). I assume there are 3 pieces of this gasket overall?
What is the temperature recommendation of the grease I need to use? I have some synthetic grease suitable for up to 356 F (temporarily 390F) called "Fuchs Renolit Unitemp 2". Will it be OK?
I have two options now:
1. Disassemble the supercharger. Grease the bearings with the grease I have and assemble it with two (one?) old gaskets and some help of "Loctite flange sealant".
2. Don't touch the bearings at the moment, assemble what was disassembled with all new gaskets and just put the supercharger back in car.
Don't know if it changes something, but my engine is at around 60k miles of mileage and (in comparision to what I did see on Youtube etc.) taking a look on the rotors, the supercharger seems to be in decent condition.
I reused the SC gearbox gasket twice with no leaks. don't use any funky sealant. The grease you have sounds good on paper, do you trust it long term?
Be sure to clean the black silicone off the bottom there, nothing sticks to silicone, not even more silicone. Use the proper sealer to replace it. I use threebond 1211 silicone because it's good enough to seal two stroke dirt bike center cases. Most anything will work on the intercooler connection though because there is no fuel or oil or crankcase fumes.
Rotors look perfect. must not have K&N's letting grit through. Stock air filters for the win!
Oh, only fill the bearings about 40%, They need air space. If they look perfect, I"d leave the factory grease alone.
Thanks a lot for your help guys. I slid the rotors out of the case and greased those bearings, just to sleep well which I couldn't if I wouldn't do it being so far already.
It appeared that the gasket between the gearbox part and the casing is different than the gasket no 3 from the pic in previous post. Seems that you can't buy it at all then.
I used "Loctite Flange Sealant". I use it at work since like 10 years already and it never failed. If it's about the grease... well who knows. But if you say it should meet the temperature requirements and it was the best bearing grease that they had in local "bearing shop" I hope it's gonna do the job.
For the next guy who searches out this thread looking for answers... Hope is not a good strategy for engine work. The reason I said if it looks perfect, leave it alone is because the rollers in that bearing need to zoom around in the outer race at extremely high speed. if the viscosity is too thick, or the bearing too full, the inner race will spin some inside the rollers, wearing at a higher rate than the 10 years they can easily run stock.
And...you don't put funky goop on the gasket because you don't need it, it won't leak. If you need to take it apart again, the gasket will be glued on and most likely get ruined. I don't know of a source to get a replacement, but IF you find one, is it oem quality and thickness? If it is please share it with the forum.
2004 E55 AMG, 2006 CLS63, 2004 ML55, 2014 E350 sport
^^I agree with if the grease looks fine leave it. Mine had very dry looking dirty grease in it and made noticeable bearing noise before repacking them. My car has done 240kms. Imo at that mileage fresh grease is doing those bearings a big favour.
I had original oem bearings brand new to observe for how much to fill these things. Basically you pack the bearing and leave the void either side of the roller bearings themselves the grease will move to wherever after its run. That is exactly how the new oem bearings come. And you 100% clean out the old grease before putting new stuff in.
Obviously the best answer is to just replace the bearings. Its not that easy though.
If anyones actually replaced them it would be good if they could put up a how to. I looked at them and was iffy on being able to remove the shells without damaging anything.
Last edited by austingtir; 08-12-2019 at 07:35 AM.
We had the intake out anyway. I decided to do some mainteneance on a supercharger then, but unfortunately the intake needed to be on it's place on monday. Yes, that's definitely not the best strategy for engine work. But...
I did grease the bearings in a proper way with high quality hi speed/hi temp bearing grease and I did touch them at all after I found a source of replacement NTN bearings for equal of 50$ per piece - just in case.
I surely didn't put any funky goop on the gasket and surely not without a reason. I found dark oily stuff between the gasket and the casing which made me suspicious so I decided to use well trusted flange sealant (Loctite 5922) which I used for over a decade assembling (and disassembling) many different engines. It's actually made to improve new/used gaskets and it's made for further disassembly of parts.
If it's about the bearing replacement. I didn't have much time to investigate it but... If a human pressed them in a human can press them out (and in again) Yes there's maybe not much space to put it on a shop press but I think some small DIY tool based on a bolt and two thick sleeves should do the job.
The bearings are epoxied into place. Apply heat while pressing/pulling the old ones out. Advance search under "supercharger bearing" will point you in the correct direction. Replacement bearings are available from Benz Performance Parts in Australia. Bearings are not a catalog item; they are custom-sized special production runs. A few years back several of us went in on a batch and it was something like a six to eight-month lead time to receive them via a bearing distributor out of Australia.
Don't mind me coobah, I was just grumpy because it sounded like you ignored my hard won advice. You sound like you know what you are doing, I don't know everything. I learn stuff on this forum almost every day. I'll have to get some of that loctite 5922 and try it . I'm always happy to find useful new chemicals.I still remember when I discovered red loctite, (292 I think it is) That was a game changer.
I don't think we ever did find the right epoxy to reinstall the bearings. I used regular JB weld on mine. It may ruin the case when it's time to change them. I just remembered why I'm saving a spare SC case!
No worries StarvingArtist. Your answer was absolutely proper as somebody who'd read that, could get an impression that it's something like "hurray let's do this with anything we have handy" type of job and... I actually didn't even have a chance to ignore any advice as I had to do this job before anyone responded here which I regret I must admit.
Anyway, despite the fact that I did it with a as much care as possible and that grease I used looked good on paper I'll surely have it on my mind for pretty long time and I'll surely remind it to myself hearing any engine noise during next couple of years
Good is, that replacement bearings will be on their way soon and my garage cabinet is more than happy to hold them as long as necessary (hopefully lifetime? )
BTW: If it's about the Loctite 5922. It's no "medicine for all evil" and it's no butter to clean up, but it's the easiest to remove good sealing goo I came across. Eg. if you use it for diff cover it'll hold for years but as soon as you remove the bolts the cover will fall off on it's own.
Could somebody please confirm, that the M113K rear supercharger bearings are NTN - RNU 0314 ZZCS25PX1/L417 and is this the whole assembly per one rotor/shaft or some extra race etc. is necessary?
08-09-2019, 05:31 PM
which I couldn't if I wouldn't do it being so far already.
