I did a search and used all the combo's like brake AND fluid AND flush but didn't find anything titled correctly.

Question is, since I'm rebuilding my calipers this weekend I want to flush out all the old brake fluid and refill with some nice new clean stuff. What is the best way to get all the old stuff out?

Use a fluid of another color, and bleed with your favorite method until the new color comes out everywhere.. then drive it a bit (to stir things up) and do it some more. (not sure baout 914s, but my Mustang calipers hold so much fluid that I can get some of the old color after a drive)

I use an old hospital vacuum pump, others use low pressure air assisted "power bleeding". The good old fashioned pump through an open bleeder technique works well, as long as you keep the end of the hose immersed in the catch bottle. Helps to let it just run out until the reservoir is empty before you begin with the new fluid. Officially, you "should" use .5L per caliper, and add another .5L for the reservoir and master cylinder. Might be overkill, but maybe not. The Cap'n

I used one of these power bleeders and a whole liter of fluid.
pelican parts power bleeder
I was horified at the stuff that floated to the top (water), and settled to the bottom (rust?) in the jar. It really made a masurable difference in pedal feel.

I used one of the power bleeders from Pelican too. Worked great on all the import cars I've used it on. Best $60 I've spent.

Pushing it out works way better than pulling it out. Like the fellow above suggested, flush it, drive it a bit, then do it again. It will stay nice longer if you get out ALL the contaminants, but it should still be done periodically. Brake fluid is very hygroscopic, or is that hydroscopic, whatever,it sucks up water like nobodies business.

Start at the RR caliper put a hose on the nipple, dump the hose in a jar immersed in a little fluid. Crack the nipple and pump the pedal, watch the resivour - once you can replace with fresh fluid (don't run it dry, or you'll spend more time bleeding). Watch the fluid to come out clean, once it does doe the normal brake bleeding technique and start on the LR, RF then LF. Repeat as necessary.

Just a little food for thought. When I was dorking around with the rear calipers I accidentally let the resevoir drain. When I put fluid in it bubbles came up so I am pretty sure I have a shit load of air in the system.

Speed Bleeders are so cool. Get four pairs.

Bleed the lower right rear until fresh fluid comes out.
Do the upper right.

left rear, right front, left front.

Done

if you still have have mushy pedal, do this.

KT

I agree with trekkor that Speed Bleeders are a BIG BIG WINNER!

Regardless, I'd go overkill and run a quart of Castrol GTX through each caliper. It's amazing what comes out, even after you've run 90% of a quart through.

After running a ton through the systemto clean it, use the Long Hose™ method, pioneered by Trekkor to bleed it.

QUOTE (Cap'n Krusty @ Aug 26 2005, 07:08 PM)

I use an old hospital vacuum pump,

Damn, my secret is out......aspirator (vacuum pump)....hook up, sit back, fill the res once in a while..........


hydroscopic....hydro = water