brake flush question

[Torinalth]

i am putting on my new cobra front brakes and rear pads, and am wanting to bleed out all my current brake fluid and refill with ford motorcraft high performance fluid (not race quality but enough for me). i have read that you dont want air backing up into the control unit... so if the brake fluid looks the same, which i am guessing it does, how does one actualy get all the fluid out for sure? and in know the order (at least the order stated by the haynes manual). so i start at the right rear and just keep bleeding till i am satisfied? or till i go through a can of fluid? thoughts?

Torinalth

 

[1999SVTVert]

You'll never be able to get absolutely all the old fluid out- Best to get as much out as possible and dilute what is left with the new fluid.

Unless you put in your old fluid yesterday, it will be quite a bit darker than the new fluid. Just bleed each line until it flows with fluid almost as clear as the new fluid.

The fluid coming out of the caliper will always be a little bit darker than right out of the bottle due to laminar flow (fluid moves fastest through the center of a tube, fluid right next to the walls doesn't flow hardly at all).

Getting it as clear as possible is your goal. Doing my Cobra about a month ago took three pints for all four lines.

Hope this helps.
Adam

 

[SigmaPride]

www.bullittarchive.com has a good writeup on brake fluid change. I used the ATE Superblue fluid, which was a different color than my greenish fluid so I could tell.

 

[nyuk98gt]

Torinalth:

SigmaPride: no flame intended! Just passing along my procedure to Torinalth.

Pick up 3 plastic bottles (12 oz. each?) of Motorcraft Heavy Duty brake fluid. It's inexpensive and very high quality (yes, it's true). You can do a 2-man brake flush or you can use a pressure bleeder (I recommend it). Bleed the four corners, working your way towards the master cylinder. Then, there are two bleed screws on the master cylinder that should be bled, too. Check out "veryuseful.com\mustang\tech..." for plenty 'o good info about Mustang brake systems and bleeding procedures.

HTH,

Chris

 

[Torinalth]

here is another quandery... i am changing out to SS brake lines, and had a thought... the haynes manual says i need to plug it right away or air will get into the controller and then i am hosed.... so i am trying to figure out what i need to do to prevent said hosing.

or is the haynes manual being over zealous in their statement? any help with this open air element i am going to face would be appreciated.

also, thanks for the assist chris, i'll check the site more when i get home.

Torinalth

 

[Kilgore Trout]

I have always wondered that myself...

 

[ToplessStang]

The important thing to remember whenever your changing a brake hose or caliper is to always keep your eye on the master and make sure it never goes dry. As long as you have brake fluid in there and no one touches the brake pedal, there will be no problem with the ABS HCU getting air in it. You must still bleed at the wheels of course once the parts are changed.

 

[nyuk98gt]

Torinalth:

If the Haynes manual didn't say it, people would let the brake system run dry and then wonder why they have major problems.... (well, that's a bit of an exaggeration but you see what I'm driving at). You can use a piece of Saran wrap or Handi-Wrap and some electrical tape or you can buy little "rubbery" caps at your local auto parts store. Just don't put anything into the brake hose or you risk contaminating it. Tiny pieces of crud in a brake system are problematic. Have the s/s hose ready to swap out and when brake fluid oozes from it, cap it off. Check the master cylinder and top it up when you do one side, as ToplessStang said.

Chris

 

[bdcardinal]

this is what i do when i change out calipers. i unbolt the old one and leave the line on the old one, usualy tie it up out of the way. i then bolt up the new caliper to the spindle and then transfer the line to the new caliper, this allows for minimum fluid loss. if i am putting on a new line i will attach the new line to the new caliper and transfer then where they connect to the hard line last. i use a container that you put on top of the master that always keeps it full.

be warned about the ford brake fluid. they changed the part number on it and the dry boiling temp dropped as well. the best all around fluids would be the valvoline synthetic DOT 3/4 ABS, or the Castrol GTLMA.

 

[Torinalth]

i am going to be going to advance tomorrow to get that AST (maybe wrong initials) Blue fluid... mainly because i am going to be doing a full bleed of the old fluid and dont want to be guessing where the new stuff starts if its the same color. thanks a ton for the quick help. i didnt think it'd be a big deal.. just had the haynes manual get me paranoid. i completely understand the need for this statement however i wish they had an "advanced" guide that eliminated some of this so as not to make me second guess myself.

so clarification.... open the hose, it will ooze/drain out... it is NOT under a vacume and will not suck air back up (as long as the brake pedal is not touched) and scerw me that way.

Torinalth

 

[bdcardinal]

correct, do not touch the brake pedal. also if you can switching to Speed Bleeders will cut your bleeding times down drastically.

 

[urban96]

to prevent an air bubble from going up into the line take the MC filler cap off. itll allow the fluid to flow down smoothly. it may cause it to flow out faster but its easier then spending more time bleeding the air out

 

[CRZYHRSGT]

correct, do not touch the brake pedal. also if you can switching to Speed Bleeders will cut your bleeding times down drastically.

Speed bleeders FTW

 

[nyuk98gt]

bdcardinal wrote: be warned about the ford brake fluid. they changed the part number on it and the dry boiling temp dropped as well. the best all around fluids would be the valvoline synthetic DOT 3/4 ABS, or the Castrol GTLMA.

Thanks, bdcardinal! I was not aware that they changed the part number and dumbed down the quality.

Chris

 

[bdcardinal]

one of the corner carvers on SVTPerformance posted that on all the applicable forums. it was a definate wakeup call.