I have an 89 cherokee with a 5 speed. The clutch pedal pushes all the way to the floor and does not come back up. The master cylinder is full of fluid and the piston does not move when the clutch pedal is pushed in. The clutch is engaged. I am assuming that the master cylinder is bad. Is there anyway to test this or should I just replace and see if that fixes the problem?

 

Get a friend and bleed the slave cylinder. If air comes out and after a few pumps fluid you will be OK. If nothing comes out then the master cylinder is gone. If either master or slave is bad, replace both. You need to pull the trans to replace the slave, so put in a new clutch at the same time. Complete kits with clutch and slave and an alignment tool are available for about $250. the Master is sold separate.