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View Full Version : Pressure Bleeding 1995 Previa Brakes setup



morevert
05-23-2025, 11:35 AM
I tried using a Motive Pressure Bleeder with there universal Master Cylinder universal Adapter that clamps on, but wasn't able to stop it for leaking. Has anyone else found a Pressure Bleeding setup that worked?

man_btc
05-23-2025, 04:18 PM
Never sprung for a pressure bleeder like that one. I've experimented with different low-cost DIY things, like adapting a pressurized bicycle inner tube to fit the master cylinder (which worked for a time, but ultimately was too fiddly and ultimately failed to maintain high pressure in the way you'd expect) and whatever those fancy bleeders are that have a one-way valve built in. I finally gave up on trying to make things "easy" and went old-school manual - running a clear tube from the bleeder in an up-and-over (inverted "U") path down into a small bottle with enough brake fluid to cover the end. Then - making sure I keep the master cylinder from running low - it's multiple trips into the van, each time depressing the brake pedal slowly like 1/2 to 3/4 of the way, then getting out to look at the tube to see if the fluid that came out is clear and bubble-free before closing off the bleeder (before detaching the tube) and moving on to the next wheel or the load-leveling brake sensor. The path of the tubing prevents bubbles from re-entering the bleeder when you release the brake (as they will rise away to the to top of the tubing bend) when the pressure releases, and the end of the tube being immersed also prevents air from being sucked into it there.

I should mention I also have a Mightyvac vacuum pump with the bleeding accessories, but found that - similar to what others posted on the interwebs and the old Yahoo forum - that when you saw bubbles in the tubing, it was never clear whether they were being cleared from the brake system or being sucked into the tube through leaks in the tubing connection and/or bleeder threads.

I also tend to use a small tie-wrap around the drain tube where it fits over the bleeder to avoid leaks of brake fluid out or air in, and to reduce the chance of an accidental disconnect in the middle of the process.