Griot's One Man Bleeder Kit

[KVH]

I'm not sure I understand the theory of that kit. You connect the reservoir to a compressed air source, loosen the bleed screw and trigger the air though the reservoir neck, I guess creating a suction effect. That doesn't seem to equate to a heavy foot forcing air out of a line.

 

[startech47]

You do not have to move the brake components, just the fluid. With the master cylinder piston in the up pedal position the fluid in the reservoir will go through the relief port and down the lines. The port is there to allow the wheel cylinders to fully retract when your foot is not on the pedal.

 

[BobbyD]

For only a few bucks you can make up this one person bleeder tool

https://tr6.danielsonfamily.org/BrakeBleedTool.htm

 

[Geo Hahn]

...trigger the air though the reservoir neck, I guess creating a suction effect...

I would call it 'pressure' rather than 'suction' if that helps.

I have used an early version (not mine) that operated off the pressure in a partially deflated tire. The pressure used is really low (don't want a geyser of brake fluid) but it did work.

As noted, there are many internet recipes for building your own from hardware store supplies.

Even Harbor Freight has a version.

OTOH, my bride enjoys the 'bonding' time helping bleed the brakes. Then we go in the house and watch a Jane Austen movie together.

 

[TR3driver]

Are you talking about this one:
https://www.griotsgarage.com/product/one-person+brake+bleeder.do
from Griots? It does work by vacuum, there is a venturi in the tool that pulls a vacuum, which then sucks fluid through the brake lines. Same principle as this one: https://www.eastwood.com/mityvac-brake-bl...CFaaDQgodhwYAUQ
except the Griots version requires a compressed air source.

With a vacuum at one end, you have atmospheric pressure pushing on the fluid at the cylinder, for around 14 psi of pressure differential pushing fluid through the system. That should be plenty (and very comparable to the 10 psi that Bobby D uses). It doesn't take a lot, all you have to do is move the brake fluid fast enough that it carries the air bubbles along with it. In fact, I find that I can gravity-bleed my front brakes (though it does take much longer that way), just the very slight pressure difference caused by the MC being above the bleed valves is enough.

I'm probably just paranoid, but Bobby's approach makes me nervous. There have been too many times when I've had liquid water and gunk spray out of my air line; I don't want to take a chance on getting that stuff into my brakes. So when I finally went looking for a one-man approach for the rear brakes (no one else around that I could bribe into pushing the pedal for me), I found these at FLAPS:

https://www.jegs.com/i/Dorman-Products/326/12704/10002/-1?parentProductId=

 

[PC]

...I would call it 'pressure' rather than 'suction' if that helps.....

Griot's "One-Person Brake Bleeder" is a suction bleeder, not a pressure bleeder.

The unit has a venturi vacuum generator that creates suction by for forcing compressed air through a constriction.

This is a major improvement over the hand pump style vacuum bleeders like a Mightyvac, which are a royal pain in the palm to keep pumping.

Griot's "Reverse Brake Bleeder Kit" is a pressure pressure bleeder.

.... That doesn't seem to equate to a heavy foot forcing air out of a line.

A heavy foot only speeds up the process. Light pressure or suction moves the fluid ok (it's incompressible), just slower.


For me, the biggest drawback to suction bleeders like Griot's and Mityvac, pressure bleeders like that diy rig Bob referenced and one-man pedal pump bleeding a la Speedbleeders is that it's too easy to lose track of how much fluid you've moved and suck/push air into the system.

I prefer systems that replaces the fluid as you bleed like Motive Porducts, Eezibleed or Griot's "Reverse Brake Bleeder Kit".



pc

 

[tomshobby]

The thing I don't like about the reverse bleed systems is that they push the dirty fluid in the wheel cylinders back into the system.