Does brake fluid go bad?
 

As the title ask, can brake fluid gum up or go bad from sitting while in what was a fully functioning brake system?

Basics behind question... car sat, calipers rusted/seized, replaced calipers, and no fluid or pressure is getting to the new caliper to compress it. There don't appear to be any flaws in the lines, and they were fully functioning before storage.

Thanks.

Re: Does brake fluid go bad?
 

It could get moisture in it and cause problems internally in the system.

Re: Does brake fluid go bad?
 

Moisture can cause the fluid to go bad. However, it wont cause your problem. There is something else wrong. I would recommend though to bleed out all of your old fluid and replace it all.

Re: Does brake fluid go bad?
 

Here's an excellent article on brake fluid.

http://www.stoptech.com/tech_info/wp...fluid_1a.shtml

How long did it sit?

Re: Does brake fluid go bad?
 

Brake fluid is hygroscopic meaning it absorbs water. Brake fluid is really a mineral oil. If you read your owner's manual or any owner's manual, you'll see that all the fluids in a vehicle need to be changed at specific intervals, including brake fluid, tranny oil, diff oil and antifreeze which many people never change.

Brake fluid is a clear liquid. If it's dark or black then it's becoming contaminated with water and should be flushed. Water in brake fluid cause rust which doesn't work inside the hydraulic system.

Re: Does brake fluid go bad?
 

I would like to be able to bleed out the fluid, but right now the two bleeders I opened aren't pushing any fluid through them.
I am leaving shortly to purchase and replace the remaining calipers and will be purchasing some brake lines in case that needs to be done. I am just confused because their appears to be no damage to the lines, and the fluid in the reservoir looks good yet it will not push the piston in the caliper or move fluid out of the bleeder.

Re: Does brake fluid go bad?
 

As far as sitting, the car hasn't done much since 2004.
It was started and ran at least once a year though the timing was off and ran rough. Oil and gas were maintained for the most part, stabil was used and now has fresh oil in addition to plugs and wires, distributor is still in great shape and was new before sitting, the fuel filter has now been changed, coolant was a fresh flush before sitting and still looks great in the new radiator, and the tranny was supposedly flushed and new filter too (i wasn't there for that part.) I didn't do anything with the brake fluid because i hadn't heard of a need to if the system didn't leak.

Re: Does brake fluid go bad?
 

Does the brake pedal move?

Re: Does brake fluid go bad?
 

The rubber brake lines are known to break down internally and restrict the flow of brake fluid, replace them and let us know is the problem persists.

Re: Does brake fluid go bad?
 

Not a bad idea. Even if the rubber lines are not the problem, getting rid of 25 year old brake lines before they collapse is a good idea.

Re: Does brake fluid go bad?
 

Yes, I have made them a routine part that I replace if for any reason I replace more than just the pads. Its nice to have that reassurance. They're about $12 a side, FYI.

Re: Does brake fluid go bad?
 

yeah definitely the line, my car sat for 4 years and i tired bleeding the brakes and nothing came out, apparently the 25 year old line didnt allow fluid to flow so its a safe bet that your problem is more than likely the line itself

Re: Does brake fluid go bad?
 

I replaced the rubber lines, since they were the problem and I was able to drive the car. First real road experience since '04. Today was a good day.
I learned I am nowhere near daily driver from the little jaunt.

Thank you much for the assistance in getting my baby back on the road.

Re: Does brake fluid go bad?
 

Awesome!

Glad we could help you figure it out! :D