Well Chris, you were warned in my #794240! “Best results in the experiment are achieved with de-lubricated steel bearings. Not a surprise, nor is it the answer! …”
My experience with washed bearings on a light Stirling Engine was initially good, but they only lasted a few hours run time – rapid wear. If, as John says, the bearing contains a material like plastic, it might also be catastrophically attacked by the solvent.
A problem with web advice is well-meaning chaps try something and, because it worked for them, assume it’s universally good. Dangerous, because their sample is far too small and the test far too short; they got lucky. Industry take far more care, fund well organised research, and get large scale customer feedback.
As there are dozens of different types of bearing and many different materials used, going off-piste isn’t guaranteed unless exactly the same bearing is used. Which is unlikely unless full details were provided. And even then, there’s nothing to stop a manufacturer changing what’s inside his bearings.
Good news is the experiment proved conclusively that White Spirit can destroy bearings. Now you can tell everyone authoritatively that the idea is unreliable!
Dave