Elektric motor bearing replacement

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Ivarsson

Member
Joined
Aug 25, 2023
Messages
5
My 2015 i3 have started to develop a mechanical wine after 163000km, after it bit of digging around on the internet it seems most likely candidate are the bearings in the motor. Due to being a mechanically savvy cheapskate the question of replacing them instead of the entire unit occurred.

Have anyone actually successfully replaced the bearings in the emotor? (instead of the entire unit)

What are the bearing dimensions?

(already checked through munrows teardown report of the e-machine and the technical training manual but without any real help)
 
Had a link towards a russian guy who documented the bearing change (poorly) on youtube. If it worked correctly after the change i do not know. The critical part is the rotor position feedback sensor, should also be whats calibrated, but he seemed to have just marked the position (unsure if it is just a pressfit or indexed)

https://www.youtube.com/watch?v=X3cpr8njfAk&ab_channel=i3MoscowClub
 
The powerpack is on a pallet now and the new bearings are in their way. Started the process of a reasonable DIY dissasembly/assembly method. (as ushual with a PMSM motor, you will have to fight the permanent magnets magnetic fields doing this). WIll try to document the procedure for future reference.
 
Was it an industry standard bearing size? If so it must have saved you a lot of money!
 
Bearing sizes for electrical motor were (2015 i3 REX)

6006 and 6306 and it were the smaller of the two that failed.
Please be aware when selecting bearings the tolerance and rpm, due to it being relativity high for the bearing size, up to 11300 rpm.

The bearings i selected were:
6006 2RZ Deep Groove Ball Bearing - SKF
6306-2RZ/C3GJN 30x72x19mm SKF Deep Groove Ball Bearing

Hopefully they will last a bit better than the originals.

A larger post regarding the bearing change is coming. Please be aware, this fix is not a quick or easy fix.
 
Have you had any issues following the bearing replacements?

How were you able to get the rotor re-installed exactly in-sync with the resolver - so that the inverter still had the proper stator/rotor timing ?
 
HELP !! the engine bearing needs to be replaced urgently, but it is difficult because of the rotation sensor. RONBOT, if I saw correctly, you were also looking for the solution, did you succeed? [email protected] Hungary
 
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