Brake fluid moisture tester
#4
SADFab Destructive Testing Engineer
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High temp fluid picks up moisture way faster than the normal stuff. And I live in one of the wetest places around.
Also tells you how bad your bottle from 2 years ago thats still on the shelf is
Also tells you how bad your bottle from 2 years ago thats still on the shelf is
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#6
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Because they don't work.
From an Australian company: penriteoil.com.au
BOILING POINT TESTING:
All passenger car, motorcycle & light duty commercial vehicle service centres should be aware that boiling point is the ONLY method approved to test brake fluid. No other method is approved or recognized as a viable test of a brake fluids boiling point.
Conductivity meters are not considered appropriate or approved for brake fluid testing - or checking. Even if it’s supplied to you by a reputable dealer with a reputable brand on it, conductivity meters are not approved by the brake or vehicle manufacturers.
To test a brake fluid’s conductivity, it’s water content must be measured and determined by the brake fluids boiling point. Brake fluid boiling point changes brand to brand, product type to product type so can vary considerably between brake fluids. Some points to consider –
Conductivity will rise as water content rises
Starting point in conductivity and rate of rise can vary greatly between formulations
If a tester is calibrated for one fluid it is likely to give inaccurate results on others. (Problem here is that it is highly unlikely that workshops are calibrating or are even able to calibrate a tester, especially one based on conductivity)
Conductivity Testers
Most of the testers used are “conductivity testers” and according to the brake fluid developers and manufacturers – They don’t work.
Conductivity testers estimate water, relying on conductivity measurement to be converted to a theoretical wet boiling point and then to a water content manifesting itself into a green, yellow or red light. Problem is conductivity of new brake fluid varies for different DOT fluids and further, from formulation to formulation within a DOT grade.
This raises the question of - What are these conductivity testers “calibrated” against or to?
Once again, a tester should be calibrated to a manufacturer’s product if it is to be used to measure that products effectiveness.
From Bendix:
Bendix does not recommend using a conductivity tester as they have been known to fail when testing freshly opened brake fluid. Conductivity testers estimate the moisture content
by converting the conductivity into an estimated boiling point. Since brake fluids vary from formula to formula,this test is not an accurate result unless the tester is calibrated to the
manufacturer’s product when new.
From an Australian company: penriteoil.com.au
BOILING POINT TESTING:
All passenger car, motorcycle & light duty commercial vehicle service centres should be aware that boiling point is the ONLY method approved to test brake fluid. No other method is approved or recognized as a viable test of a brake fluids boiling point.
Conductivity meters are not considered appropriate or approved for brake fluid testing - or checking. Even if it’s supplied to you by a reputable dealer with a reputable brand on it, conductivity meters are not approved by the brake or vehicle manufacturers.
To test a brake fluid’s conductivity, it’s water content must be measured and determined by the brake fluids boiling point. Brake fluid boiling point changes brand to brand, product type to product type so can vary considerably between brake fluids. Some points to consider –
Conductivity will rise as water content rises
Starting point in conductivity and rate of rise can vary greatly between formulations
If a tester is calibrated for one fluid it is likely to give inaccurate results on others. (Problem here is that it is highly unlikely that workshops are calibrating or are even able to calibrate a tester, especially one based on conductivity)
Conductivity Testers
Most of the testers used are “conductivity testers” and according to the brake fluid developers and manufacturers – They don’t work.
Conductivity testers estimate water, relying on conductivity measurement to be converted to a theoretical wet boiling point and then to a water content manifesting itself into a green, yellow or red light. Problem is conductivity of new brake fluid varies for different DOT fluids and further, from formulation to formulation within a DOT grade.
This raises the question of - What are these conductivity testers “calibrated” against or to?
Once again, a tester should be calibrated to a manufacturer’s product if it is to be used to measure that products effectiveness.
From Bendix:
Bendix does not recommend using a conductivity tester as they have been known to fail when testing freshly opened brake fluid. Conductivity testers estimate the moisture content
by converting the conductivity into an estimated boiling point. Since brake fluids vary from formula to formula,this test is not an accurate result unless the tester is calibrated to the
manufacturer’s product when new.
#7
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So, am I reading this wrong, or are these things basically just an ohm meter? So build a little bracket to hold the two probes of your multimeter a fixed distance apart and start measuring the resistance of new and old brake fluid. If the problem is calibration variances between different brands of brake fluid, just measure your brand new bottle and then measure some old stuff that's been sitting around.
#10
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Because they don't work.
From an Australian company: penriteoil.com.au
BOILING POINT TESTING:
All passenger car, motorcycle & light duty commercial vehicle service centres should be aware that boiling point is the ONLY method approved to test brake fluid. No other method is approved or recognized as a viable test of a brake fluids boiling point.
Conductivity meters are not considered appropriate or approved for brake fluid testing - or checking. Even if it’s supplied to you by a reputable dealer with a reputable brand on it, conductivity meters are not approved by the brake or vehicle manufacturers.
To test a brake fluid’s conductivity, it’s water content must be measured and determined by the brake fluids boiling point. Brake fluid boiling point changes brand to brand, product type to product type so can vary considerably between brake fluids. Some points to consider –
Conductivity will rise as water content rises
Starting point in conductivity and rate of rise can vary greatly between formulations
If a tester is calibrated for one fluid it is likely to give inaccurate results on others. (Problem here is that it is highly unlikely that workshops are calibrating or are even able to calibrate a tester, especially one based on conductivity)
Conductivity Testers
Most of the testers used are “conductivity testers” and according to the brake fluid developers and manufacturers – They don’t work.
Conductivity testers estimate water, relying on conductivity measurement to be converted to a theoretical wet boiling point and then to a water content manifesting itself into a green, yellow or red light. Problem is conductivity of new brake fluid varies for different DOT fluids and further, from formulation to formulation within a DOT grade.
This raises the question of - What are these conductivity testers “calibrated” against or to?
Once again, a tester should be calibrated to a manufacturer’s product if it is to be used to measure that products effectiveness.
From Bendix:
Bendix does not recommend using a conductivity tester as they have been known to fail when testing freshly opened brake fluid. Conductivity testers estimate the moisture content
by converting the conductivity into an estimated boiling point. Since brake fluids vary from formula to formula,this test is not an accurate result unless the tester is calibrated to the
manufacturer’s product when new.
From an Australian company: penriteoil.com.au
BOILING POINT TESTING:
All passenger car, motorcycle & light duty commercial vehicle service centres should be aware that boiling point is the ONLY method approved to test brake fluid. No other method is approved or recognized as a viable test of a brake fluids boiling point.
Conductivity meters are not considered appropriate or approved for brake fluid testing - or checking. Even if it’s supplied to you by a reputable dealer with a reputable brand on it, conductivity meters are not approved by the brake or vehicle manufacturers.
To test a brake fluid’s conductivity, it’s water content must be measured and determined by the brake fluids boiling point. Brake fluid boiling point changes brand to brand, product type to product type so can vary considerably between brake fluids. Some points to consider –
Conductivity will rise as water content rises
Starting point in conductivity and rate of rise can vary greatly between formulations
If a tester is calibrated for one fluid it is likely to give inaccurate results on others. (Problem here is that it is highly unlikely that workshops are calibrating or are even able to calibrate a tester, especially one based on conductivity)
Conductivity Testers
Most of the testers used are “conductivity testers” and according to the brake fluid developers and manufacturers – They don’t work.
Conductivity testers estimate water, relying on conductivity measurement to be converted to a theoretical wet boiling point and then to a water content manifesting itself into a green, yellow or red light. Problem is conductivity of new brake fluid varies for different DOT fluids and further, from formulation to formulation within a DOT grade.
This raises the question of - What are these conductivity testers “calibrated” against or to?
Once again, a tester should be calibrated to a manufacturer’s product if it is to be used to measure that products effectiveness.
From Bendix:
Bendix does not recommend using a conductivity tester as they have been known to fail when testing freshly opened brake fluid. Conductivity testers estimate the moisture content
by converting the conductivity into an estimated boiling point. Since brake fluids vary from formula to formula,this test is not an accurate result unless the tester is calibrated to the
manufacturer’s product when new.
#11
Retired Mech Design Engr
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So, am I reading this wrong, or are these things basically just an ohm meter? So build a little bracket to hold the two probes of your multimeter a fixed distance apart and start measuring the resistance of new and old brake fluid. If the problem is calibration variances between different brands of brake fluid, just measure your brand new bottle and then measure some old stuff that's been sitting around.