How to grease the supercharger bearings if they're closed?
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.
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.
Last edited by coobah; Aug 10, 2019 at 03:14 AM.




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.
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.
Last edited by coobah; Aug 10, 2019 at 06:59 PM.
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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.
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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; Aug 12, 2019 at 07:35 AM.
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.
Last edited by coobah; Aug 12, 2019 at 03:38 PM.








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!
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?
Last edited by coobah; Aug 13, 2019 at 04:17 PM.




Last edited by bbirdwell; Aug 13, 2019 at 04:26 PM.


