Brake fluid is hygroscopic. However if it's been in a sealed container there shouldn't be a problem. If you suspect it might have water in it you can always bring it to boiling temp to remove the water.
https://www.mynrma.com.au/cars-and-driving/car-servicing/resources/understanding-brake-fluid#:~:text=Brake%20fluids%20are%20hygroscopic%2C%20what,the%20vehicle%20is%20not%20driven. Rich ________________________________ From: KRnet <[email protected]> on behalf of Mark Langford <[email protected]> Sent: Saturday, November 19, 2022 10:38:26 AM To: mark jones via KRnet <[email protected]> Subject: Re: KRnet> Brake Fluid Mark Jones wrote: Does aviation brake fluid have a long shelf life? I have some that must be at least ten years old. Is it safe to use? Just use it. I've been using the same one gallon can for 20 years, and it's fine. I'm sure somewhere you can find some short shelf life cited....probably from somebody that sells it, but I don't see people in a rush to change their brake fluid at annuals. If it ain't broke, don't "fix" it. I did some research on it (admittedly a year ago, which is forever in my brain), and I was not concerned. Also, I've learned the "exercising" brake cylinders past their normal limits is risky business, because o-rings go places they are not used to going and do funny things, so it's best to leave that stuff alone, in my humble opinion, FWIW. Of course it you fill the brake system from the wheel up, this is not usually an issue. It's the bleeding through pumping stuff that can get you in trouble. Mark Langford [email protected] http://www.n56ml.com Huntsville, AL -- KRnet mailing list [email protected] https://list.krnet.org/mailman/listinfo/krnet
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