I have used the vacuum bleeders on my C3 and couldn't get them to work well...especially on the rear.

I have speed bleeders on the rear brakes and have found success with those. I don't use the vacuum on them, I use old fashioned brake pedal push. That is the most success that I have had with my C3.

Other cars I can gravity bleed or use a vacuum pump without a problem.

Don't forget that there are two bleed screws per caliper on the rear of C3's.

 

I finally got around to using the above mentioned BikeMaster vacuum bleeder to bleed my brakes.

First of all it was the neatest and fastest brake bleed I've ever done. The tool it self is well made and does what it advertises.

The only problem was that my brakes weren't any better. Three of my calipers have lip seals and one has o-rings that I used when it leaked.

The BikeMaster vacuum bleeder worked like a champ on the o-ring caliper, but not so well on the lip seal calipers. There was a noticeable difference on the vacuum between the two types of seals.

It pulled massive amounts of fluid from all bleed points with ease, but something just wasn't working right on the calipers with lip seals. You could see air mixing in with the brake fluid on the rear and front lip seal calipers and the rear o-ring seal caliper produced some air bubbles and then a solid thick stream of brake fluid.

I expected air from the rear lip seal caliper only, but not the lip seal fronts and they all looked the same when being vacuum bled.

I ended up doing the bleed using speed-bleeders and finally got a hard pedal. I also flushed the synthetic DOT 3/4 fluid I had been using and returned to regular mineral based DOT 3 brake fluid. I think the synthetic was trapping air bubbles. I haven't done a test drive yet since it was so late when I finished last night, but pedal feel has a night and day difference.

Even though the BikeMaster didn't work as well as I had hoped. I'm sure if I had all o-ring calipers it would have given me a good bleed all the way around.

One side note, the BikeMaster was worth the money I paid just for all of the contaminants and hard varnish type stuff that it removed from my brake system. I was amazed at the crap that was being removed. I thought I had a fairly clean system since I had never seen this kind of stuff the many other times I had bled the system. Was I ever wrong.

One of these days, after more pressing issues are addressed on the car, I'll change all of the lip seals to o-rings and give the BikeMaster another try. But then again, I may just go with a Wilwood brake system instead if I find myself with a few extra coins in my pocket.

Good Luck!

 

This is what I do.

Big C-Clamp to hold this on top. One connector for front or rear. I use a cork gasket on the bottom plate. Apply about 10 PSI from my compressor and bleed away. The down side is I need to watch the amount I bleed so I dont run the master cylinder dry. But its good for about a 30-45 second bleed before filling the master again.

 

Personally I wouldn't use anything that uses VACUUM. Think about it, what are you going to suck easier, air or fluid? The smallest little leak in the bleeder, which by the way is just threads waiting to leak air, and you suck air, although it may be into the bottle.

Pressure is the best way. If you can push from the bottom up there would be no air at all. The problem is that we can get onto the bottom very well and push up. On the rear you can if you disconnect the hard line at the caliper, but then you have to open it up and reconnect. A T-shape connector with a one-way valve permanently installed would be the awesome. One could hook up to it and push fluid up the caliper and up the line (this is assuming you aren't working on and old system and pushing junk up the line).