New Way to BLEED the CLUTCH!!!!

[windrider]

A guy I know, called about a motorcycle he had just purchased, and was having hydraulic clutch trouble.  I remembered all the thread on here, and I'll make a long story short.

I have an old fashioned handheld metal pump oil can.  Then kind we oiled our bicycle chains with.  It has the metal spout, and the lever that is long and you squeeze with your hands.  (sorry, no picture at moment).  A large syringe would work also.  

Do not have any oil in this pump, but instead, fill it with brake fluid.

Get a piece of flexible tubing, slip it over the end of the oil pump, and slip the other end over the bleeder.  take the top off the master cylinder, and lay it aside.  Wrap the master cylinder with nice clean rags.  Now open the bleeder, and slowly start pumping.  Wait a few seconds between, strokes.  Watch for air bubbles if you can, and when you see no more, and you have fluid coming out of the top of the master cylinder on every pump of the little oil can, you should have a nicely bled system.  Good Luck, and hope this helps somebody.  

Picture is not mine, but close enough to give you the idea.

[Option13]

This is a lesser known way of bleeding hydraulic systems, and it's supposed to work better because you're not trying to convince air to flow downhill. Not trying to rain on your parade, but it sure does feel good when you think of something yourself, even if you later find someone else beat you to it.

I was working on the clutch MC tonight, and rather than bleed all that air out through the bottom, I just cracked the MC banjo bolt a bit since the lines still had fluid in them. Definitely could be a time saver, unless there is concern about the crush washers not taking well to this process.

[windrider]

On small Cessna and Piper aircraft, and others, this is the only way to bleed the system, as the bleeders are at the bottom of the calipers.  The air will never get out, they must be bled backwards.  I usually like to push the fluid up through the master cylinder to help flush out the return passages to the master cylinder.The crush washers will stand a few reuses, if you leave them on the same fittings they came from, but not many. 

[jonboy 69]

 in using this backwards system do you have to depress the clutch or brake levers at all to allow the rearward flow?  do you want to be careful coming to the end of the stroke on your oil can as well?  any threat of putting air in the system with this can method?  thanks  .....

[windrider]

As for the oil can, it won't put air in the system, not even at the end of it's stroke, at least not the one I use.  As depressing anything, not required.  Now, if you start with a totally dry system, you will have air in the master cylinder.  Once you get the master cylinder about half full.  close the bleeder on the slave cylinder, and give the master cylinder several slow and complete pumps.  This should get the air from the master in to the lines.  Now open the bleeder on the slave, and pump the oil can and you should see bubbles come up in the master.  Repeat as needed, maybe twice.