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Discussion Starter · #1 ·
Hey all, I put on a new set of rear brake pads on yesterday afternoon, and when I checked the fluid level (first time on this Boss), I noticed that the fluid was not the purple color I have always used in the Bosses. Does anyone know what type of fluid the factory put in a 2002 model? When I purchased it, it only had about 2000 miles on it, so I am sure that the fluid that is in it is from the factory fill. I have the DOT 5 silicone fluid I always used in my '97 Boss, but I am afraid to put it in this 2002. The fluid I got out of this one (when I squeezed out the fluid as I put the new pads on), was a yellow color (looks like regular brake fluid). I am not sure whether to use the silicone (purple), or regular fluid. I thought maybe someone here knows what the factory used in 2002...maybe a silicone based "yellow" fluid? Maybe regular DOT 3 or 4? I definately don't want to mix them, as I know from experience they don't mix. Thanks all!
Mike
 

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Mike,
you should use DOT5 in any case. If your fluid isn't purple- that doesn't
mean that's it's no DOT5 fluid. I for example use ATE DOT5 fluid which is yellow - just like organic based brake fluid. If a dealer filled your system with regular fluid (like mine did), then flush the system several times, and fill it with silicon based stuff.

Loaf
 

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Discussion Starter · #3 ·
HMmmm..Anyone have any ideas how to tell if the fluid in the system now is silicone based or regular? I hate to start flushing and bleeding system...I never have much luck on bleeding the braking system.
 

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It came as silicone from the factory and if it was changed you would probably be leaking. The fluid in almost all the Boss Hoss's I have looked at was dark because of the heat and was discolored. Just clean it out, flush and refill with dot 5.

Adrian
 

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The purple color eventually becomes yellow. The same is true of Royal Purple Motor Oil...Turns honey colored in a few hundred miles. Forget the color. I have used only DOT 5 fluid for 5 years and have changed many times. Purple in...yellow out..Joe
 

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Any ideas on how to flush the brake fluid? I'm getting ready to do a rear master cylinder overhaul and need to flush out the DOT 3 that I accidently put in there.

Alan
 

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awilks said:
Any ideas on how to flush the brake fluid? I'm getting ready to do a rear master cylinder overhaul and need to flush out the DOT 3 that I accidently put in there.

Alan
Alan

I have done this several times with our hot rods. We put in dot 5 for the show circuit and then flush them out with Denatured Alcohol because it does not leave any kind of residue. I have also done it like you need to do and the denatured works like a champ.

Adrian
 

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Adrian ,

When you say you flush the entire system with denatured alcohol do you men you fill the master cylinder with alcohol and pump it thru the lines until it comes out the bleeders clear or do you suck the alcohol thru the lines from the master cylinder using a MITY VAC PUMP connected to the bleeders ?

Jack
 

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Jack
Yes that is how I do it.
I pump it thro like you do when you use the brake fluid. I suck it thro every thing from the calipers then bleed it, let it air out and then put in the brake fluid (dot-5).

Adrian
 

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Adrian,

I think you just answered "Yes" to an either/or question. What I think you said was that you pump the alcohol through from the master cylinder, just like you were using brake fluid. I think I'll do that before installing my new brake kit. That way, I won't take the chance of messing up my new gaskets with the alcohol.

Am I right?

Alan :lol:
 

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Discussion Starter · #11 ·
I think I will get some denatured alcohol, use my mity vac to pull out all the old fluid, fill the master cylinder with the alcohol, use the mity vac to flush it out through the bleeders until it is clear, then refill with fresh DOT 5 and bleed out the air. Does this sound like the right approach? Another question Adrian, I have had probs in the past on my other Boss with getting all the air out of the system. If I understand the proper procedure, you turn the bleeder (you are working on at the time) upside down, toward the ground, as low as possible (making sure it is lower than the master cylinder), and bleed one cylinder at a time in this manner. Is this the correct manner? Thanks all...
 

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NO, Mike...you want the bleeder nipples as high as possible and upright because air rises to the top and you want the air going out through the nipples as you release them. The rear caliper is easy to hold higher than the master cylinder but the fronts are not. I reverse bleed them by forcing the pads apart with the front master cap off whih pushes the air up into the master. Have someone keep steady pressure on the brake pedal or front lever and you open and close the nipple while the pressure is held. Close the nipple down before the pedal is released otherwise you'll suck air into the system. Keep repeating the process until no air comes out through the nipple just fluid. When the air is out, pump the pedal or lever several times until you get a hard brake and the pads are against the caliper...Joe
 

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awilks said:
Adrian,

I think you just answered "Yes" to an either/or question. What I think you said was that you pump the alcohol through from the master cylinder, just like you were using brake fluid. I think I'll do that before installing my new brake kit. That way, I won't take the chance of messing up my new gaskets with the alcohol.

Am I right?

Alan :lol:
Alan
Most other brake fluids will mix but if you start with dot 5 it will not mix with any other type. You are correct so if you made a mistake by adding any other type then you must clean it out and flush it. I know of nothing else that will work like the denatured alcohol. I buy the stuff in a gallan can and it will last a life time. I also use it for cleaning up brake parts I need to use again.

Adrian
 

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Discussion Starter · #14 ·
Thanks! I suppose I have been doing things backwards for years on the other Boss! I have bled systems on cars all through my life, but a dealer told me on the Boss, to point the nipple down, and hold it as low as you can, to get all the air out. (I guess this is the reason I have always had problems with the Boss brakes in the past). Thanks Adrian...I will flush the system out this week. This site with all you knowledegable people is a Godsend!
Thanks,
Mike
 

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Discussion Starter · #16 ·
Thanks guys...The method I have used in the past on the Boss'es didn't work, but the way Adrian stated, works perfectly! I had the complete system flushed, bled, and a great pedal feel within 45 minutes. Now...I had to ride to work today just to see if the new pads really create less dust on the rear wheel... :D
 
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