Brake Fluid moisture tester
#1
Le Mans Master
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Brake Fluid moisture tester
Has anyone ever used one of these? Are they accurate? Waste of time?
#2
Racer
might be a neat tool but all brake fluid will absorb some moisture and suck up some dirt. i myself always look at the fluid and if its dark i just replace it with new. it never hurts to keep your fluid clean.
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Avanti (07-12-2019)
#5
Melting Slicks
Agree with above.Unless it's colored,most BF's ( and clutch)look like ginger ale when clean.
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Last edited by dbaker; 07-12-2019 at 06:15 AM.
#6
How are you going to test the moisture at the calipers? The brake fluid won't be consistent from reservoir down to calipers. It doesn't circulate and mix.
#8
E-Ray, 3LZ, ZER, LIFT
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These are the results:
My first drain fluid showed 3% moisture. At 4% requires changing. On the 7th drain it was zero, the same as the new fluid in the container!
Brake fluid is very hygroscopic (picks up water like a sponge!) That moisture will diffuse though the fluid from calipers to reservoir and will NOT be significantly different!
SIDEBAR
The product I received was in an obviously designed for US in a sealed blister pack. All US English no other language. Probably excess from a lot made for a US supplier who paid $1 and sells for $10! The Chinese give free mailing as a way to increase exports! Real fair completion! For me to ship a small item to China in a small Priority Mail Box it cost $35! Crazy.
Last edited by JerryU; 07-13-2019 at 07:14 PM.
#9
Le Mans Master
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Yeah my brake fluid after two and a half years and 10k miles showed <1% but the clutch was 4%. I flushed brakes today and had to get a turkey baster today to do the clutch later this evening.
#10
Le Mans Master
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Oh, and I also used it to check a can of brake fluid that I had opened some time back to see if it was ok. It measured zero so I figured it should have been fine.
#11
Yep, it measures resistance and probably fairly accurate. I saw one on Amazon for $10 and then the same one from China (where no doubt the one on Amazon was from) for ~$2 free shipping on eBay. Ordered for fun as I thought I would check the fluid as I did the Ranger Method for clutch fluid.
These are the results:
My first drain fluid showed 3% moisture. At 4% requires changing. On the 7th drain it was zero, the same as the new fluid in the container!
Brake fluid is very hygroscopic (picks up water like a sponge!) That moisture will diffuse though the fluid from calipers to reservoir and will NOT be significantly different!
SIDEBAR
The product I received was in an obviously designed for US in a sealed blister pack. All US English no other language. Probably excess from a lot made for a US supplier who paid $1 and sells for $10! The Chinese give free mailing as a way to increase exports! Real fair completion! For me to ship a small item to China in a small Priority Mail Box it cost $35! Crazy.
These are the results:
My first drain fluid showed 3% moisture. At 4% requires changing. On the 7th drain it was zero, the same as the new fluid in the container!
Brake fluid is very hygroscopic (picks up water like a sponge!) That moisture will diffuse though the fluid from calipers to reservoir and will NOT be significantly different!
SIDEBAR
The product I received was in an obviously designed for US in a sealed blister pack. All US English no other language. Probably excess from a lot made for a US supplier who paid $1 and sells for $10! The Chinese give free mailing as a way to increase exports! Real fair completion! For me to ship a small item to China in a small Priority Mail Box it cost $35! Crazy.
#12
E-Ray, 3LZ, ZER, LIFT
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Color is NOT a good indicator! You can buy test strips but these meters are cheap and work. Frankly I do the Ranger Method once a year so no need to measure as I do it whatever! I bought the meter because it was so cheap (just checked eBay and saw several for $2.99 free shipping from China!) I wanted to perform those tests when I did the Ranger Method!
GM says the color in the clutch fluid (DOT 4 brake fluid) comes from staining by the seals cause it to turn black quickly (I assume the graphite -or whatever- seals on the throughout bearing. Brake fluid dissolves paint so assume it will pick-up other "stuff" as well.) My color change is from draining the old fluid, putting in new and pumping the clutch 30 times. Repeat that ~7 times. Uses most of the 12 once containers I buy. Like to start with a new container ($4) where there is an unbroken aluminum foil seal on the new container.
GM says the color in the clutch fluid (DOT 4 brake fluid) comes from staining by the seals cause it to turn black quickly (I assume the graphite -or whatever- seals on the throughout bearing. Brake fluid dissolves paint so assume it will pick-up other "stuff" as well.) My color change is from draining the old fluid, putting in new and pumping the clutch 30 times. Repeat that ~7 times. Uses most of the 12 once containers I buy. Like to start with a new container ($4) where there is an unbroken aluminum foil seal on the new container.
Last edited by JerryU; 07-14-2019 at 07:14 AM.
#13
I change my brake fluid yearly from tracking and the remainder of the bottle goes to the clutch so i was just curious too.
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JerryU (07-14-2019)
#15
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The problem with using a brake fluid tester is it might work better if it is calibrated for the type of brake fluid (DOT3 or DOT4) you are using to get proper results. Here is a DOT4 calibrated unit on Amazon:
Here is a tester supposedly calibrated for both DOT3 and 4:
You pay your money and take your chances.
Bill
Here is a tester supposedly calibrated for both DOT3 and 4:
https://www.amazon.com/dp/B076SC377J/ref=sspa_dk_detail_0?psc=1&pd_rd_i=B076SC377J&pd_rd_w=niVoO&pf_rd_p=8a8f3917-7900-4ce8-ad90-adf0d53c0985&pd_rd_wg=dX4aL&pf_rd_r=90K1H161NZ17PKMERW08&pd_rd_r=bfbad28e-a7e2-11e9-b6f8-915155cfcbac
You pay your money and take your chances.
Bill