Loud fan on R4

[fishdogduck]

I just received a second hand bitmain R4, getting a good hashrate but it's quite loud for an R4 (around 65-70 dB while it's supposed to be 52dB). I've taken it apart removing the fan and when turning it manually i can hear a sort of crunching sound which i'm guessing is metal in the bearings. Only problem is now i'm not sure how to take the fan bearing cover off without breaking it. Has anyone had experience in repairing these or ideas to make it quieter? https://i.imgur.com/az3KsHc.jpg

[slurfius]

I would like to replace mine as well let me know if you find a replacement I've looked and couldn't find one.

[ncsupanda]

I resolved this too many times to count with some WD40. Curious what you come up with otherwise.

You can always pick up a new shroud from a non-working unit and swap out the hashboards.

[BitMaxz]

Any grease spray might be work but I think the bearing should be replaced if grease does not work then your last hope is to replace the bearing the only problem it looks like it's hard to remove the metal under that fan motor. It seems that you need a puller to be able to remove the metal part on the motor.

If you have a motorcycle tool you can may be able to pull that metal part the tool looks like this one below