My 850 clutch pretty much goes to the floor. There is some action at the slave cylinder and there are no leaks. If I pull back the a bit on the fork at the slave cylinder, the fork is loose , but still feels mounted to the pivot. There was no noise to indicate throwout bearing seizure.

Is there any way to isolate the problem to the master vs. slave vs. throwout?

Thanks for any help.

 

If the 850 is like most hydraulic clutches there should be a bleeder valve on the slave. Try seeing if you can bleed the valve (ie force out some fluid with a slow push of the pedal). Typically they share brake fluid from the brake resevoir - did you notice any fluid loss? Can you get any action if you pump the clutch? Look around for leaks - ie have somebody work the clutch pedal while you look for any fluid coming out - all it takes is a little air to stop the slave from moving.

 

Yes, I tried the bleeding, maybe need to do more as the reservoir was right at the min. Topped it off before attempting to bleed. So, may be a slight leak, but there is no fresh fluid outside the system.

I'll look at it some more tomorrow.

Thanks!

 

My advice is this:

In a situation where the master goes to the floor, and you've bled the slave, then the slave cylinder can only leak. It has no other failure modes, period, end of story. If the slave is leaking, replace it.

Since you didn't say every time you step on the clutch that all the fluid goes to the floor of the garage, then I would say the master is the problem. The master has plenty of failure modes that can be exhibited by the pedal going to the floor. One of these modes is having the hole between the reservior and the cylinder barrel plugged up with a piece of trash. YOu can fix that for free, and that is the only reason I mention it. That probabaly isn't your poblem.

 

Do you have an internal or external slave? If external, have someone push the pedal while you look at it. If internal, get a mirror and flashlight then pull back the rubber and look at it. Does it move when the pedal is pushed or stay put?

 

Been away form this for a few days, it is an external slave and has action when clutch pedal is pushed, just not enough to move the throw out bearing arm to disengage clutch.

Looks like a high probability its the master cylinder.