I Need Help With The Brake Bleeding

Well, I've been thru a full gallon of brake fluid, I've completely lost the rear brake lever and it doesn't seem to want to come back even after hours of bleeding, literally, from both the bleed valve on the front caliper and the valve on the rear caliper.

There seem to be very small air bubbles now, especially when I first open the valve on the rear caliper, they actually look almost like foam. Then they go away. Both valves run mostly "clean", that is, it looks like only fluid is running thru, most of the time, but the brake lever remains completely lost. It compresses all the way to the grip, with virtually no resistance.

I'm stumped, frustrated, and without ideas.

I know I let air into the system 3 times, twice by letting the master cylinder suck air, and once by pumping the rear lever many times while the bleed valve was open, not knowing that this would suck air into the system.

I would have thought though that by now, with so much fluid and so many hours of bleeding, that this would have been cleared up. How much fluid can this operation actually take, and how many hours can it take?

Any advise or suggestions are greatly appreciated.

Matthew, Are you manually or using a commercial bleeder? Do you have a Service Manual and using it as per section 16? I don't mean to offend you by asking these questions? But it helps to know what steps you have used up to this point.

Getting major contamination of air in the system can be a real nightmare, but it is repairable. Post briefly what steps you have taken. Take a deep breath. Maybe open a cool diet Coke or Pepsi. Just remember, you are only bleeding 2 wheels, it could be worse if it had 4. Help is on the way.

Gary

Some of you long time 2 wheel persons... do you know any special things to know about the brake system mechanics of the Swing that is different from other hydraulic brake systems? I have never done the brake thing on the scoot, but I have done major brake repair and replacement to automobile systems. Gained a few wrinkles doing them, but all turned out just fine.
I have a 2002 Service Manual and it is pretty well laid out what to do. I did not see any special notes. But I know that sometimes experience adds little footnotes to procedures that the book leaves out.
Lets all give Matthew a hand here.
Gary

For what it's worth -- don't forget that the "rear" brake lever also has a single pot on the front caliper that must be taken care of.

No offense taken Gary. I've followed the shop manual procedures for bleeding the old fashioned way (without the "professional bleed kit") after talking with my mechanic. This actually improved the rear lever back to about where it was before I started any of this.

As I stated, I did introduce air into the system 3 different times, and both he and I think this is what is causing the remaining problem of a lever that moves too far. I actually took the scoot to him, and he bled everything again the old fashioned way, with no additional improvement over what I had already achieved at home. This is why he speculates that there is additional air remaining high up in the system - air rises, as he pointed out - and he suggested riding for a few days and bleeding again (without the new fangled mity vac) to see if more air can be bled at that time. I guess that's what I'll do.

Funny that I achieved better results using the simple pump the lever/open the valve/close the valve/release the lever method than with all my vacuum pumping for three days and a gallon of fluid. The old method uses hardly any fluid at all. Or maybe it's just that there isn't much air left in the lower parts of the system to be bled out with more fluid. I'm babbling. I don't really know what I'm talking about. Hopefully this will resolve itself in the next few days.

In the meanwhile I'm right back where I started from, if only a little worse for wear. Oh, I did spray some brake cleaner on each rotor and on the pads, and now the squeak from the front brakes seems to be gone. Hooray.

I really appreciate the responses. Thanks a lot.