PGN (2 Pack) 6204-2RS Bearing - Lubricated Chrome Steel Sealed Ball Bearing - 20x47x14mm Bearings with Rubber Seal & High RPM Support

I removed the seals and cleared the grease of this two pack. One bearing was as expected smooth, clean, fast and worked as expected with a little bit of synthetic lubricant. The other bearing on the other hand masked its imperfections rather well until I removed the seals and grease. I have put it aside due to the terrible Grinding / grating noise it generates. I have ordered a second pair 6204 to hopefully get a second good bearing to complete my project. These bearings are being used for a 3d printed cut away jet engine so I will not be putting a heavy load or generating heat from high speeds.