Foamy brake fluid DURING flush

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so last night I did complete flush for the brakes. front right side was little foamy on the top of the bottle.

the color of the fluid was more like "Honey color"

its easy job but my concerns now are:

1- does the little foamy indicate that the fluid was contaminated?

2- did compete flush but the color has not changed much, shouldn't be with no color just like water? in the tube was yellowish
 
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What color was the new brake fluid (in sealed can), I'd keep flushing until that color. Brake fluid should only be used from sealed can, as it attracts moisture. Moisture is the contaminate.
 
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When flushing the break system, I was advise to turn on the ignition (Not start the engine) to activate the ABS system to flush fluids in the system.
 
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Foamy is usually air, I agree with above post that ignition is to be on. It takes alot of fluid to do a full fluid change. Best to do it with 2 people, I bought a pipe with a one way valve in but the pressure just kept blowing it off.
 
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thanks,

I used Toyota brake fluid,( transparent). during flush it didn't turn to that color ( bought only 5 bottles 12 oz). it was sealed.
I successfully did the flush with ignition on all around but maybe got 80% of the old fluid.
I figured the foamy was air, good thing I flushed. I will re-flush after 30K again.

Thanks
 
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The foam you are seeing is most likely being caused by air bleeding in through the bleed screw threads during the bleeding process. There is no way the fluid in the calipers or anywhere in the system would be "foamy" or stay foamy while within the system.
 
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If you follow the brake bleeding FSM procedure BR-4 you can't go wrong ;) iirc you've got an '07 so you should also be able to do the ABS bleeding as well. If the ABS ecu tab is available in Techstream select it and you'll find ABS bleeding under the utility tab. Very quick procedure and it ensures the older fluid retained in the ABS side is refreshed.
 
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Never let reservoir get to low while flushing as this will allow air in system. I bleed using clear tube into glass jar, for visual inspection.
 
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The foam you are seeing is most likely being caused by air bleeding in through the bleed screw threads during the bleeding process. There is no way the fluid in the calipers or anywhere in the system would be "foamy" or stay foamy while within the system.
Or Henry's Gas Law. A gas (air) under pressure in solution (brake fluid) will expand (foam) when the pressure is relieved - think opening a bottle of soft drink.
 
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If you follow the brake bleeding FSM procedure BR-4 you can't go wrong ;) iirc you've got an '07 so you should also be able to do the ABS bleeding as well. If the ABS ecu tab is available in Techstream select it and you'll find ABS bleeding under the utility tab. Very quick procedure and it ensures the older fluid retained in the ABS side is refreshed.

Hey PADDO :) it is 07.
i followed the procedure in MUD plus some youtube videos ( i did it correctly) but didn't know about the tech stream ABS flush. Thanks for pointing it out. will do that in the next one as i think i did semi flush.

Never let reservoir get to low while flushing as this will allow air in system. I bleed using clear tube into glass jar, for visual inspection.

i did the same exact thing but fluid was not 100% flush as i bought only 5 bottles 12oz. Thanks

The foam you are seeing is most likely being caused by air bleeding in through the bleed screw threads during the bleeding process. There is no way the fluid in the calipers or anywhere in the system would be "foamy" or stay foamy while within the system.

ya the foam was only on the top of the clear jar, i kept flushing till made sure no air in the tube. Thanks
 
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Agree that air was most probably introduced during the bleeding process, as you would of had a spongy pedal before, as long as you have good brake pedal now then all is good.
 

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