DIY: Supercharger oil refilling
There doesn't seem to be any issues caused by overfilling apart from the possibility of that smelly oil leaking out the sc bolt and splashing on the underside of the hood, although for many people (including myself) filling to the drain hole does not cause leakage?




Denroll, may I ask you to provide the diameter of the supercharger shaft in millimeters? And the outer bearing diameter and the width. I would estimate the shaft diameter at 17mm, the outer bearing diameter at 26mm, and the width is unknown.
The NTN RNU is a custom-made bearing; thus the non-availability. Might want to look into teaming with a company such as ECS Tuning for a larger run to reduce costs. This bearing is used with any supercharger on the M113 engine. I would much rather spend a couple of hundred dollars replacing the bearings versus spending thousands of dollars on another supercharger.
The reason I ask Denroll for the measurements is it is possible one could install non-standard bearings (most likely a deep-groove ball-bearing in "Series 8" diameter) as a rebuild that would suffice to meet the requirements of the original design.
The 6203Z bearing normally comes with a 17mm inner bore (the "03" in the designation) but the "2" is a standard metric measurement (usually starting at 40mm but the supercharger bearing looks to be a custom 26mm). The "6" indicates "ball bearing" but that can also include "cylindrical bearings". FWIW, the RNU from NTN indicates "Custom, cylindrical bearing, caged". The "03 indicates inner bearing diameter (17mm), the "ZZ" indicates sealed on both sides. The rest of the suffix deals with clearances and whatnot.
If one does decide to repack the bearing with grease, choose a high-temp grease and only pack the bearing to 50% of the volume.
I would much rather rebuild my supercharger at 120K miles rather than have it fail catastrophically.
Apologies for the long-winded post but we need to make it financially viable for NTN to produce another run of these bearings.








I looked around and have not found a definitive answer on preferred lube for our specific application ... so, after finding that some (many) supercharger re-builders use an NLGI 1.5 (or ... NLGI 2* depending where it is listed) grade grease called "Rheotemp 500" I just ordered up a 100 gram tube. Likely hundreds of times the amount I need, but this is the smallest container that TAI http://www.lubekits.com/ had on hand (they are the north american dist for Nye, the manufacturer of Rheotemp 500).
with shipping, it was about $75
I expect I will have plenty left over to share : )
Cheers,
Chris
Last edited by latemodel21; Nov 17, 2015 at 02:02 PM.
The Best of Mercedes & AMG
Last edited by new55; Nov 16, 2015 at 01:27 PM.








I like the idea, however, ALL of the original grease must be removed AND when re-greased, this bearing should get a 30% fill or less (70 - 75% air-space left in bearing after re-lubing)... SO to force out ALL of the old grease (if that were even possible) while only re-filling 25-30% seems IMpossible ....
So it would seem there is no way to do this properly without removing the inner race (which is pressed on the shaft in this application) ... then flushing (with solvent) and then refilling.
Cheers,
Chris
Last edited by latemodel21; Nov 24, 2015 at 03:48 PM.




So it would seem there is no way to do this properly without removing the inner race (which is the shaft in this application) ... then flushing (with solvent) and then refilling.
Cheers,
Chris
I bought a used S/C and took one bearing out of it, so these bearings are worth a thousand bucks apiece if you really need one.




The inner race is tight with very little lip, so sharpen and thin out your puller, and clearance the other end so the jaws squeeze in close to the center. Grease the screw and center tip. Once you get it to bite, hose clamp the jaws in place.
I used temperature difference and a hammer to reinstall, went smooth. For epoxy I used slow JB weld in a syringe because it can take the heat, but I will have a hard time getting it out next time.
These bearings turn a lot faster than the pulley because of the gearing, so don't use anything inferior.
Oh, and be carful with the gaskets on the other end, they are reusable, and probably hard to find.




Cheers,
Chris




I feel slightly confused by the bearing pics on page 4 and 5.. Where does the grease go? Is it as simple as greasing the rollers or? Starvingartist's second bearing pic on page 5 has me perplexed as I'm trying to figure out what is on top of the bearing in his second picture of the two he posted.. Can someone guide me a little? I have yet to ever pull my SC off and am just trying to put the pieces of information in this thread together.
Last edited by Bean93x; Jan 13, 2016 at 06:47 PM.
I would like to know what's up with the replacement bearings as well.. I see there is a plant delivery for the end of this month... Hopefully we can see these before the end of 2016


