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Discussion Starter · #1 ·
I want to drain the brake fluid reservoir and fill it with fresh fluid but the screen does not seem to come out and a small vent across from the cap seems to be where fluid should be added but not removed. Is there a trick to removing the screen under the cap without destroying the screen? If you have had success removing old fluid please let me know how you did it. Thanks
 

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Following.

I have been wanting to do the same but the correct way is to get new fluid in and continue to push the old fluid out till new fluid flows out all four corners. Simply draining and refilling the reservoir is leaving a lot of old fluid in the system so you aren't gaining anything.
 

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As jj said you are not accomplishing anything by just changing out the fluid in the reservoir.
A Motive brake bleeder and flushing the complete system is the way to go.
But, you can remove the screen with a little effort. There are 4 small tabs (marked with black dots) holding it in place. Look for the recesses around the edge of the screen housing and using a very small flat screw driver (Jewelers type) Gently pry between the recessed lip and the mouth of the reservoir to release the tabs. See photos. As you can see from the second photo there is little to be gained from removing the screen. There will still be a lot of parts blocking you from getting to the bottom of the reservoir.

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Discussion Starter · #6 ·
Thank you all for the replies. I will remove it next weekend and see how much fluid I can extract using a syringe attached to a small clear tube. As I said, I'm only trying to do a drain and fill, not a complete bleed of the brake system. The brakes are fine, I just want to extend the interval between bleeding. I used my syringe on the two small holes to the left, but only removed about 2 ounces of fluid, hence I'm trying to go deeper into the reservoir. I don't drive as many miles as before so the car is sitting 5 days per week. At 225K and still going strong I want to keep the car while doing minimal maintenance. Thanks again.
 

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Bleeding is minimal maintenance. Replacing what is in the reservoir "reserve tank" won't do anything to extend the life of the fluid in the lines. It doesn't circulate. If you aren't willing to bleed it, which is a simple procedure, you might as well not do anything to the fluid.

Now, to make bleeding faster, drain the tank and fill with new fluid so it starts to push new fluid through the system sooner.
 

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Bleeding is minimal maintenance. Replacing what is in the reservoir "reserve tank" won't do anything to extend the life of the fluid in the lines. It doesn't circulate. If you aren't willing to bleed it, which is a simple procedure, you might as well not do anything to the fluid.

Now, to make bleeding faster, drain the tank and fill with new fluid so it starts to push new fluid through the system sooner.
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Bleeding is minimal maintenance. Replacing what is in the reservoir "reserve tank" won't do anything to extend the life of the fluid in the lines. It doesn't circulate. If you aren't willing to bleed it, which is a simple procedure, you might as well not do anything to the fluid.
Are there any Chemists here who know whether new, 'dry' brake fluid has a lower specific gravity than fluid with absorbed water? If so, the contaminated fluid would tend to gravitate to the wheel cylinders, along with the worn off rubber particles from the piston cups and piston seals.
 

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Or the absorbed moisture in the old fluid may simple 'wick' back up into the new fluid. I think brake fluid attracts water so maybe the new 'dry' fluid would pull the water out of the old fluid.

It would be interesting to drain and the fill the reservoir with new fluid that is a different color and then bleed the brakes a week later to see how much 'mixing' occurred. Of just use new clear fluid in the reservoir and see if it turns dark after some period of time. Or just bleed the brakes - it isn't a big job - and rusty wheel cylinders are not a good thing.
 
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