Clutch Master Cylinder Not Pumping

Just bought a 03 VFR800 and was noticing the clutch engage was rough. Opened the master cylinder reservoir and found it was extremely low and had a layer of sludge in the bottom. After draining and cleaning out the reservoir and refilling it wont pump fluid. I did try and bleed the system the old fashion way with no luck. I then disconnected the banjo bolt at the MC and pumped the lever but I got no fluid being pushed out. I have pumped the lever for at least 5 minutes and get no change in the fluid level. Any suggestions?

 

Welcome to VFRWORLD. Sorry to hear of your disfunctional clutch m/c.

It sounds like you will have to rebuild the master cylinder, which is not difficult or expensive.

 

This happens sometimes to VFR masters, both brake and clutch.
It can be caused by a bubble in the top of the chamber.
You can get rid of it by filling the master, closing it up and removing it from the clipons.
Then angle it so the line connection is to the bottom, and shake it and move the leaver taking up the slack on the against the piston rapidly.
If you do this with master opened, you can see air bubbles coming to the surface, after that it will pump normally so you can bleed the system.
Worth a shot.

 

If you just purchased the bike and prior owner let the fluid get that low and old that it became sludge I recommend that you rebuild it and the slave cylinder while you are at it since the slave is probably also sludged up. Not an expensive or complicated job. On a 14 year old bike with neglected fluids it is likely that the seals are shot and better to start off fresh to avoid future issues.

 

You might not be bleeding the mc correctly. Take off the bango, then squeeze the lever and place a finger over the hole every time the lever is on the return stroke until pressure builds with finger held against the hole. Keep lever squeezed while you replaCE BANJO AND TiGHTEN FULLY.

Finger off the hole then squeeze; finger ON the hole as lever returns may create the vACUUM TO DRAW FLUID THROUGH.

tHEN bleed down at the slave to remove sludge and bad fluid.