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One man bleeding and Brake fluid/ATF

Thanks for the info on the different ways…gravity,vacuum,pressure @ mastercyl.The only controversy seems to be the purging of the debri from the wheel cylinders. But ironically (I love irony, unless I’m on the painfull end) I received noting on my 1st question which is…If my tube from the open nipple is under a few inches of brake fluid(in a jar), couldn’t I just pump the pedal(medium force) without sucking in air ? Also, can ATF (recomended on master cyl cap ) be added to brake fluid ?

Brake fluid is brake fluid. ATF is ATF. If the nipple is not closed before the pedal is released it may suck old fluid under your proposition, the goal is to replace the brake fluid, not reintroduce old brake fluid. I have heard of all types of substitution fluids for other fluids but why play the russian roulette game as the recommended fluid is not a price buster concept. You can certainly find 1 person to help you and do it right.

Now you will need the manual. It will identify where you can put what. Some vehicles have hydraulic power assisted brakes but I didn’t think your car had them. I wold get the Haynes manual before I worked on your brakes if your car were strange looking to me.

To answer the bleeding question: Maybe it will work and maybe not, but it isn’t the procedure in my manual. You can do it that way with the self bleeding hose which you can get at Sears or at a parts store. It isn’t expensive.

About that debris. Despite any controversy, I have never seen any manual or training manual that says to worry about anything like that. Just worry about the things it tells you to worry about.

“Also, can ATF (recomended on master cyl cap ) be added to brake fluid ?”

NO it can not!! Perhaps the cap belongs on a power-steering pump…It certainly does not belong on the master cylinder…Or someone just stuck that label on the cap…

Sorry, My mind was in neutral; I had recently replaced my power steering hose (Napa $40 - Toyota $215) so I meant to say “mix ATF (as printed on the cap)” with a generic/off brand power steering fluid in the Pwr Steering resevoir.I’m going to try my vacuum jar tomorrow. As far as the 1st question. I would of course start with 3"of new fluid over the tube end…I’m thinking, tho it’s just a guess that the push out would be around 80% and suck back at 20%…so after the last flow of clean airless fluid you could pump and prop/ wedge the stick/2 x 4. Have a peaceful Sunday. try Chris Botti, relaxing slow jazz. Mike

I’m thinking, tho it’s just a guess that the push out would be around 80%
and suck back at 20%.

This makes no sense. I don’t know if any of us can say what percentage of “old” fluid would get sucked back in.

Also, the old fluid contains the moisture that you’re trying to get rid of. Why would you want to suck any of that moisture back into your brake system?

Yes you can bleed the brake fluid via gravity the way you described. Just be sure the tube is sufficiently long enough which shouldn’t be a problem if it’s down to the bottom of a jar on the ground. And you don’t need a couple inches over the end of the tube. As long as the end is covered you should be fine and you won’t suck air in. If you have the help, then it never hurts to do it the 2 person method. I do both with no problems. The hose/jar method is particularly helpful when you’re trying to do a brake fluid replacement.

I’ve done the 2 man way 5-6 times with good results. Since I will be by myself it seemed logical that I could open the farthest bleeder with the tube in a jar(with some fluid) and pump away without touching the nipple till the fluid is clean, then give one more push, wedge the stick (so no suck will bring in any of the dirty fluid) close the bleeder…then go to the next wheel.I read that too agressive pumping could damage the Master cyl seal…Mike