Mike,
Neat with the vacuum pump.
On other thing to try is to PRESSURIZE the reservoir.
I know this sounds odd, but you can do this two ways:
1: some adapter to fit over the top of the master cylinder.
Apply pressure to the master cylinder.
Crack open the bleeder, fluid comes out.
2: reverse flow the system. Common on aircraft, is to pressurize
the bleeder. Fluid comes up and overflows out the master cylinder.
Either way what you are doing is working with a pressurized system.
I have used the mighty vac with DISC brakes just fine. With the
wheel cylinders, the vacuum is not normal and will draw air past
the wheel cylinder piston seals. They work fine with a pressure
differential, having higher pressure on the brake system to flare
the seal out. With a vacuum, I am not as successful on bleeding the
brakes.
OTHER TRICKS:
Flip a small can of brake fluid up, and into the master cylinder.
It will sit there, upside down, only refilling the reservoir when
the reservoir level drops below the lip of the inverted can of
brake fluid. Of course if the can falls over, big mess!
NEXT TRICK:
Use a pressure jar, full of brake fluid. Low tube (into the fluid)
is tied to a special master clinder cap to fit the reservoir. As you
pressurize the car, excess fluid flows up into the master cylinder.
You crack open the bleeder to release fluid. I have seen commercial
bleeding systems like this. Nice trick, and quick.
Use caution with pressure, or vacuum. You should only need 10 psi
to move fluid through the system. With the vacuum bleeder, I would
wrap the bleeders with teflon tape around the threaded portion to
prevnt air leaks. That is how I discovered the leaking rear wheel
cylinder, making it hard to bleed to rear brakes.
To hold the top of something to the reservoir... mentally picture
a flat disc about 1" diameter. Threaded hole in the disc, for a
brass tubing fitting. Rubber inner tube between the top disc
and reservoir. Velcro strap to hold it in place... fun little
project.
Cheers,
Tom Walter
P.S. Wear safety goggles with the pressurized brake fluid!
>Tired of using my Mighty Vac to bleed my brakes, I came up with a new
>idea to accomplish the task with a minimum of effort.
>
>I purchased an A/C vacuum evacuator from Harbor Freight for about $20
>and hooked it up to my compressor and in between the brake bleeder screw
>and the evacuator I placed a vacuum container to collect the fluid which
>came w/ the Mighty Vac. Now I don't have to constantly pump the Mighty
>Vac to get vacuum, especially when changing all the brake fluid in the
>system.
>
>But, you have to replace the fluid in the master before it runs out of
>fluid and you can't run the compressor @90 PSI or it'll suck the fluid
>out too fast. I am still working on the right pressure to use but 60 PSI
>seems OK. I tried it out last night on water and it works well.
>
>You can make your own fluid collector with a glass jar and some plastic
>vacuum connectors and such which I bought from Home Depot. Just put a
>length of tubing on the side that gets connected to the bleeder screw to
>make sure the fluid goes to the bottom of the jar. The side that gets
>connected to the compressor leave w/no tube or you defeat the purpose of
>the tube.
>
>Sorry I have no pictures or diagrams - yet!
>
>Mike
>66 1819
>
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