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by rpcope1 309 days ago
WD-40 isn't a lubricant, 3 in 1 is really a cutting oil and too thin, and I can't imagine lithium grease doing well in a high speed bearing...it's really only good because I think it's less toxic. These are all real thin and not appropriate in a bearing. I'm not sure about petroleum jelly, but as crazy as it sounds I've packed all sorts of bearings including fan bearings with basic synthetic marine grease (the pink shit that comes in tubs and grease cartridges), or occasionally heavy weight synthetic gear oil (think 75w90), and profoundly improved the life of things and reduced drag. Only real drawback is god forbid you get real grease on your clothes or something you care about cause it's not coming out.

Also if it came packed with graphite or something else exotic none of the above applies and doing the above can burn a motor out.
1 comments
GuB-42 309 days ago
> WD-40 isn't a lubricant

WD-40 is a lubricant. The WD-40 company says it is [1], the Wikipedia article says it is, attempts to reverse-engineer the (secret) formula have found compounds typically used as lubricants and it is rather obvious to anyone who has used it.

It is the best lubricant for you application? Probably not, and that includes fans. It is probably not the best at anything unless you have an Atlas missile lying around. It is not the best lubricant, penetrating oil, water displacer, rust protector, etc... but it does all of it to some extent, and it is cheap and convenient.

Anyways, thank you for the suggestion of using gear oil, I didn't try this one and it sounds like a good candidate. I don't have marine grease but what I understand is that it is similar to basic lithium grease but formulated to resist the harsh marine environment (so maybe with some corrosion inhibitors).

[1] https://www.wd40.com/how-to/faqs/

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rpcope1 309 days ago
I mean I'm sure water could be considered a lubricant too, but it's almost never a good one. WD-40 I'm sure in some technical sense can function as a lubricant but it's a really crappy one and if nothing else tends to dry out quick. Even as a penetrating fluid it's pretty shit even compared to liquid wrench or ATF and acetone. I don't know why people bother using it other than as a water displacer.

Marine bearing and chassis grease is really different than white lithium grease. Lithium grease in general probably isn't advisable on a fan the more I think about it as it tends to destroy plastic and rubber. On a real bearing like a wheel bearing even a thin coat of high pressure grease like synthetic marine grease is going to outperform basically everything else (unless you've got an oil pump involved), and again would be the first thing I'd try and pack a bearing of rotating assembly with hands down. t's probably cheaper or about the same if you go pick up something like a tub of Supertech synthetic marine. I'm sure if you go ask somewhere like BobIsTheOilGuy forums someone there will be able to point to an optimal solution.

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