Brake Fluid Hydrometer

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Brake Fluid Hydrometer

Postby kleggo on Tue May 10, 2016 7:44 am

I wonder how accurate / precise these are?

A friend recently gave me one and it purports to measure H20 content in your car's brake fluid.
Very quick process, ~ 5 seconds once I had the master cylinder cap off.

If anywhere close to accurate with decent precision, these might be a good tool in the tech team's arsenal.

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Re: Brake Fluid Hydrometer

Postby Steve Grosekemper on Tue May 10, 2016 7:24 pm

Very accurate and its in the tech box.
Only used on cars that are suspicious, not all.
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Re: Brake Fluid Hydrometer

Postby Old Guy on Wed May 11, 2016 8:39 pm

I have one. Will be happy to carry it along to whatever event if someone will just remind me to do so. Otherwise, as little as I'm getting out and about these days, it'll sit on the shelf with the battery running down.
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Re: Brake Fluid Hydrometer/fluid disposal?

Postby Old Guy on Mon Jun 18, 2018 12:48 am

Update. I kept it alive by removing the battery; reinstalling it only when I need it. Last week I replaced the brake fluid in our V50. The moisture meter was reading in the red: 3-4%. Before that I replaced the brake fluid in our M3 even though the meter measured less than 2% moisture (and was less that 2 years old)...but I tracked the car at Fontana's May Bimmerfest so wanted to feel safe. I had on the shelf some cans of Super Blue; yeah, bought several years ago...but never opened. (BTW, even the one opened can I had (opened about 3 years ago; closed since then)...measured "green" as in "just fine" on my tester...<1% moisture.) My tester is an FTE W0040.

Brake fluid disposal? One shop I trust tells me just to mix it in with old oil and send to oil recycling. Another shop I trust tells me that since it is water soluble, simply flush it down the toilet. ??

Input or advice re which is correct, or at least "the best"??

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