Checking brake fluid and clutch fluid

[Bru]

The question that is common and nagging is not knowing if the brake and clutch fluid still good. There are several ways to test it including a conductivity tester or even using a voltmeter. I bought one of those conductivity testers on eBay for about $7 delivered and it seems to work pretty well. My bottle of dry brake fluid tested below 1% water. The brake master cylinder reservoir tested below 2%. When water gets to 3% or above, it's time for a fluid change because water lowers the boiling point of the fluid not to mention system corrosion. When I tested the clutch master cylinder it was above 4% or off the scale of this device. I went ahead and changed the fluid by drawing what was in the reservoir out with a syringe and a short thin hose. I refilled the reservoir and did the bleeding using a one-man bleeding check valve and hose to flush out was in the line out the slave cylinder. I've had good results with Valvoline DOT 3 – 4 synthetic brake fluid. The dry boiling point is 480° which is better than average for a DOT 4 fluid. Mark III Supras were made in the era of DOT 3 brake fluid but this DOT 3 – 4 works fine. Ideally, brake and clutch fluid should be changed every 3 years. Here is a link to an interesting article about brake fluids and also a link to the eBay seller of these testers. One strange thing is that the plastic it's made of has a chemical odor.

https://www.speedwaymotors.com/the-t...ications/28676

https://www.ebay.com/sch/i.html?_fro...rt=nc&LH_BIN=1