Anyone ever try the gravity bleed method? I've heard that it works really well but I cant find much about it on the interwebs.
yeah im trying to avoid spending much money for brake jobs. what do you do with the vacuum just attach to the nipple and pull out all the fluid? Do you add fluid at the same time?I picked up a vacuum device from Harbor Freight for just a few $. Does a great job changing out the brake fluid.
Well... I got essentially blasted on another forum for suggesting it as a method. so I was just checking here, where people are slightly more reasonable in their reasoning and opinions.As long as you're simply trying to flush the brake fluid, you want to avoid air entering the lines and calipers. So yes, keep adding fresh fluid to the resorvoir while draining at the calipers; no matter if gravity, vacuum or pump'n'bleed is your choice.
Can't imagine any of the three will make a significant difference in how efficiently/quickly the old fluid is being replaced...
when I did a gravity bleed I didn't even move the lever. I just opened the cap to the master cylinder and unscrew the bleed nipple to get a steady flow and then I fill as fluid drains out. Once its all clear I put my thumb over the nipple and pull off the hose then tighten the nipple so fluid cant come out. Then I pull the lever as hard as I can and hold it while I put the cap back on the master cylinder. Does that sound okay or do you see any problems with that method? Last time I changed my fluid it lasted over 6000 miles before getting brownish as it was before I changed it.If you're talking about tying the lever and opening the bleed screw, it's an unreliable method; the fluid can take a while to get moving, and once it does, it comes out fast, and you can end up with a dry system. Pump 'n bleed ensures the pressure is always going the right way and that the amount is always in your control; plus, it's fast and requires no special tools, which I like.
Again, for large air pockets, like when I put on new lines, I find that injecting in from the bleed screw is the quickest and most controlled way to fill those pockets with fluid. You just have to make sure that the reservoir is open and not over-full (since you'll be pushing air and some fluid into it), and that you start the pressure before you open the screw and only relieve the pressure once it's closed. Then top off the reservoir and bleed conventionally.