Warning about brake fluid

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Oct 5, 2006 | 01:16 PM

#21

jrp

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From: Littleton CO

Quote:

Originally Posted by rocco16

As long as the bottle is tightly capped after you take the fluid from it, it should be good for many, many months. A good-fitting cap is airtight....at least as airtight as the cap on the MS reservoir.

Thanks... I bought two bottles, knowing that I would take a while to finish the project and having read that some people don't store the leftovers, but then it did occur to me that it won't be any more exposed than the fluid in the master cylinder.

Oct 5, 2006 | 01:24 PM

#22

C4boy

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From: Red Sox Nation! RI

If I recall correctly, plastic brake fuild containers are more susceptible to letting in moisture than metal containers. I don't know what the shelf life is.

The main difference between synthetic and DOT 3 brake fluid is the boiling point. Synthetic has a higher boiling point, but you can still attract moisture in a line with synthetic fluid.

Oct 5, 2006 | 01:29 PM

#23

onedef92

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From: Fort Knox, KY

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Do not put DOT 5 silicone brake fluid in ABS-equipped cars, either, because it will bubble under pulsations.

Oct 5, 2006 | 05:21 PM

#24

Corvette Kid

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From: Good health is merely the slowest possible rate at which one can die

St. Jude Donor '04-'05-'06-'07

I only put in fluid from a fresh container in my cars. When a container has been opened and some has been used, there's more room for air in it. Air is what the fluid absorbs moisture from. I flush mine at least yearly in the Vette. Another benefit of keeping clean fluid in the system is that you'll have much less hydraulic trouble with the system as time goes by. I also always recommend flushing the system before replacing pads. This way you're not pushing the pistons back into dirty fluid.

Oct 5, 2006 | 07:38 PM

#25

bogus

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From: San Pedro CA

if you all are intent on throwing out the left over fluid, at least add it to your dirty motor oil, so it can be recycled!

Waste is one thing, but waste without recourse of some sort is just tragic.

I also use Synpower in my clutch, so consider saving it for that use... the heat factors are not as great, so a little moisture won't be totally terminal.

The reason brake fluid is hydroscopic is so it will absorb the moisture, not the brake components.

Oct 5, 2006 | 07:48 PM

#26

85 500 horse

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From: Obama=death for America

Quote:

Originally Posted by murraybob

I was driving down a long mountain road thinking I was doing a good job of not riding my brakes so that the fluid wouldn't boil. I didn't downshift, just used my brakes sparingly. Guess what! About the time I got to the bottom of the canyon, my brakes went out. Pedal to the floor and no brakes! I thought I must have sprung a leak in the brake system, wheel cylinder or something. After about 15 minutes my brakes came back, full pedal. I obviously boiled my fluid.

I was baffled as to why the fluid boiled so easily. I have lived near the mountains all of my life, so I know something about driving in them.

The next day on the speed channel,Two Guys Garage or something like that, they explained what the problem was. They said that brake fluid will absorb water vapor from the atmosphere and over time it can get enough water in it to significantly lower the boiling temperature of the fluid. The brakes can easily generate enough heat to exceed the boiling temperature of watered down brake fluid. The answer is to service the brake fluid often enough to keep it relatively free of water.

Since we are all driving C4s that are all at least 10 years old, this advice probably applies to all of us.

Live and learn!!

Thanks for sharing. I change my brake fluid every 2 years only because it gets a bit dirty and I don't like having dirty fluid. I did not know that it absorbs water over time. People who ignore this critical maintenance must are just asking for major problems - Sorry sir; I don't know what happened to my brakes...

Oct 5, 2006 | 08:48 PM

#27

2008 Atomic Orange

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From: Vero Beach Florida

Great tip, thanks.

Oct 5, 2006 | 09:31 PM

#28

jaa1992

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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps

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St. Jude Donor '12

Quote:

Originally Posted by 85 500 horse

This is a known problem in the owners manual. It does not spell out a frequency for replacing your fluid. If it looks dirty Flush it!!!!!!
Mine sees about 8 track weekends a year and gets bled before and after each event and flused every year. I switch between ATE Blue and Gold. Its about $10 per can, I use two cans per year (one for the flush and one for the top off after bleeding). How can you argue about spending $10 and 1 hour to flush the system per year????