What is the best way to flush/bleed the brakes when flying solo? I usually suck out what’s in the master cylinder with a syringe the refill with fresh fluid then proceed with the pump and hold method. This vehicle does NOT have ABS. I need to get this car done asap & back to it’s owner and have no help. Anybody have a technique for this situation?
I use a mityvac bleed helper which is basically what you’re doing with the syringe. One of those rabbit water bottles with the ball taken out hanging ipside down, with the spout into the reservoir, comes in handy to keep the it automatically filled.
Remove the bleeder screw and coat the threads with grease and reinstall the bleeder screw. Take a container and fill it part way with brake fluid. Take a hose and connect one end to the bleeder screw and take the other end and emerse into the brake fluid. Each time you press the brake pedal brake fluid will be pushed out. When you release the brake pedal the brake fluid in the container will be drawn back in. This will prevent air from being drawn back into the brake system each time the brake pedal is released.
I use Tester’s method since I have given up on my wife or daughter doing a proper job at pumping the brake. Maybe they are doing it just fine, but pedal feel has not been there. At the end of the bleed process, I do some gravity draining of the fluid. You need some time to do it, but gives me the best pedal feel.
I like testers method as well, but I use a small container that I can tie to the suspension somewhere above the bleed valve, that way the air in the hose goes up and to the container instead of back into the caliper. I add the brake fluid to the jar by opening the bleed valve and letting the fluid gravity fill the hose and part of the container.
Baby food jars work as do some single serving yogurt containers or small juice bottles. I get clear plastic aquarium hose from Wally World for about $4 for 25’ for the hose from the caliper to the container. Drill a hole in the container cap to hold the hose in place.
When you step on the brake pedal, be sure to hold it to the floor for a few seconds to let any air bubbles in the hose rise to the top, then let up slowly so that they stay at the top.
And if you are really ambitious:
“Each time you press the brake pedal brake fluid will be pushed out. When you release the brake pedal the brake fluid in the container will be drawn back in.”
As I understand your method, old fluid is pushed out and mixes with new fluid in the jar. So, what gets drawn back in would be mixture of old and new? If that’s right, why are we not concerned about bringing back in some of the old fluid? Is it because only a minimal amount is drawn back in?
Yeah, I’m a little confused too. I want to exchange my fluid when I do pads but have always done the two person method. So if you use the pressure tank, when you open the bleed screw, will the fluid bleed out or do you have to push the pedal down too?
When I do this, and I am doing a flush, I first set up a tube at each caliper/wheel cylinder. Then I suck out all the old fluid from the MC reservoir and put in fresh. Then I open all the bleeders a good ways so that the fluid starts draining. I keep the reservoir topped off and let it gravity flush until the fluid in the tubes becomes clear. Then I dump the old fluid and let fresh in until it covers the end of the tubing and the tube is full.
After that, I work the brake pedal, one wheel at a time. Only clean fluid in the lines for the bleeding part. I also barely crack the bleeders at this time so it is harder for the fluid to be drawn back in.
I normally do what is called a gravity bleed.
1 pull fluid out of m/cyl with the turkey sucker to remove old fluid.
2 fill with new fluid.
3 remove bleeder screw and clean it out with small drill bit or similar
4 fluid will be run out of caliper or w/cyl. no big deal, air will not get sucked up into the line.
5 reinstall bleeder but don’t tighten. let it run until new fluid comes out and no bubbles also.
6 don’t let the master cyl run dry!
7 repeat for all effected corners.
8. clean your mess.
9 if all went well you should have a nice firm pedal.
I also prefer Tester’s method. As long as you keep topping off the reservoir, you can push all the old fluid out the bleeder and never get any air drawn back in.
I can state with absolute certainty that opening a bleeder about 1 turn and connecting a snug fitting piece of rubber hose 4+ inches long and pointing upward will allow pumping the brake pedal and flushing each caliper and wheel cylinder. It is important to monitor the master cylinder reservoir to prevent pumping air into the system.
It’s my belief that gravity brake flushing will not cause turbulence inside each brake cylinder needed to stir up debris that can then be expelled through the bleeder valve. It’s much better to use a helper to firmly push and hold the brake pedal while a second person operates the bleeder valve. Lacking a helper, you can get new fluid into the system as described by others.