Brake fluid resivoir looks like a hot tub with the blower on.

[Meisterbr?wn]

*UPDATED* Power Steering fluid resivoir looks like a hot tub with the blower on.

OK folks, the dumbass of the day award goes to me. I said my brake fluid resivoir was a churning mess, it's my *power steering* resivoir....

Ugh. The last post about having ACE or not got me. I started to reply "no ACE, my power steering resivoir is only for steering only...oh crap".

So anyway, the power steering resivoir really gets churning when the motor is running. Sorry for the confusion.


Original post:
I was looking under the hood yesterday while the engine was running and noticed the brake fluid in the resivoir was roiling like the proverbial tempest in a teapot.

It seriously looked like a blender on high speed - brake fluid was sloshing all over.

I can't imagine this is S.O.P., so does anyone have an idea? Braking has been fine, and brake fluid level has been stable.

I bled the brakes about 5k miles (10 months) ago. Should I do it again? Is this a symptom of air in the lines? When I bled them last time, it was a two-person job. If I do it again, I'm investing in a pressure bleeder.

Truck is a 2000 Discovery II with 65k.

Thanks D-web Brain Trust!

 

[D Chapman]

Was it just vibrating?

 

[Meisterbr?wn]

I'm not sure if you meant the resivoir, brake pedal or something else, but nothing is/was vibrating. Just the brake fluid sloshing around.

 

[andrewv]

It recirculates like that on purpose. It is SOP, but I don't remember what the claimed benefits are supposed to be.

 

[marc olivares]

have to agree w/ Dan, but that's not to say that it might be something else..

open your hood and grab hold of the res. and see if you can settle the sloshing by holding it. that would at least rule out the vibrating. can you hear your ABS pump running?
yank the abs fuse? does it still slosh around?
still think it might be the vibe from the motor but worth looking at other things too.

edit: i just noticed you have a D2, fuse pulling my not ba an option.

 

[KevinNY]

My 04 does the same thing.

 

[Meisterbr?wn]

OK, just re-read Dan's post after Marc's.....

I certainly didn't notice the resivoir shaking, but that doesn't mean it wasn't. The more I think about it, there is very little surface area of the brake fluid in the resivoir and even a subtle vibration could cause a disturbance (much the same way the coffee slops out of my Starbuck's cup with even the slightest shake)....

I'll investigate at lunch. Thanks for all the advice.

 

[pdogg]

Could it be the ACE pump ? does yours have ACE? I test drove a '01 SE w. ACE and it did the same thing. My '02 SD non-ACE doesn't pump the fluid into the resevoir like that.

 

[mikemeyer0]

My 04 does the same thing.

 

[andrewv]

IT'S SUPPOSED TO DO THAT! Now, if I can remember why, I'll let you know.

 

[pdogg]

I double checked my non-ACE SD last night.. sure enough the brake resevoir is swirling like a hot-tub... so you can ignore my previous incorrect post.

 

[andrewv]

Sorry as well. I read churning like a hot tub, and immediately thought PS reservoir and never paid attention to you saying Brake Fluid. It's a sealed, open loop system, and you see it bubbling because they didn't fit any kind of plate or baffles.

 

[pdogg]

I was curious and did some research on why it recirculates. If it's truly a recirculating brake system, it's designed primarily to keep the brake fluid cooler, by always having fresh fluid passing through the system, preventing overheating.