Brake fluid (Opened Can)- is it usable?

[fazil]

I have an opened can of Castrol Dot-4 brake fluid. I've used half of the can 2 years ago and closed its cap tightly.

I want to change front and rear brake fluids of my bike these days.
Do you recommend to use it or just buy a new one?

 

[Downs]

Pour a little out and see if it's still clear. If there's any brown tint to it or dark in anyway throw it out and get some new stuff.

 

[mayassa]

No dump it and get new, it absorbs water (moister).

 

[Downs]

No dump it and get new, it absorbs water (moister).

Which will cause it to take on a tint other than clear.

 

[Norbert]

just get a new bottle.
it's not expensive.
2 years is a long time.

 

[Cribbe]

When it comes to brake fluid always buy a new one when it is time to change. The cost i low regarding what can happen if you use old fluid...

 

[mayassa]

Which will cause it to take on a tint other than clear.

I always thought heat and the sun (UV) made it turn color. I learn something new every day.

 

[FinalImpact]

NEW from a sealed container as you really can't see the moisture in it.
Can you see the moisture in the air on 50% humidity day? NO! But its there! Its also why you try to do brake fills/flushes on the LOW humidity days to keep the system dryer longer.

The color is from integral components like the rubber pistons wearing in the bores, rubber brake lines, rust from steel parts oxidizing, aluminum from those parts eroding, and all other parts of the system degrading that typically give it color other than clear. But yes, add enough water and it will haze.

Its the H20 that breaks down the system shortening its life.

 

[Marthy]

I have an opened can of Castrol Dot-4 brake fluid. I've used half of the can 2 years ago and closed its cap tightly.

I want to change front and rear brake fluids of my bike these days.
Do you recommend to use it or just buy a new one?

Junk it! Brake fluid is like moisture magnet! If it's more than a few months old get new one. I use to put a date on it in my racing days... But since we were bleeding the brakes almost every day it never been a issue but all the stuff we had in the trailer were getting junk during the off season.

 

[MisterX]

I'm with the previous posters. Dump it and get some new fluid. Like Marthy said, brake fluid is a moisture magnet. Unless it's sealed, it most likely will have absorbed some water and lessened its effectiveness. It doesn't cost that much and is definitely worth doing right. Especially when it comes to your brakes.

 

[fazil]

Ok. Thanks for all the replies.
I'll go with a new one.
I don't want any water in the brake lines.

 

[sparkycrew]

brake fluid should be changed every two years anyway,so the new fluid in the container as been in contact with air in the container so it is already due for changing although it hasnt been used,excess moisture in brake fluid turns it black,apart from corrosion to internals,it lowers the boiling point,having said that i have seen fluid last decades in clutch hydraulics where people overlook changing it,for the price of half a litre of fluid change it and be happy you did the right thing,also some insurance companies may test the fluid after an accident,be safe and cover your @ss my freind