No clutch pedal pressure

no fluid in the clutch reservoir due to a failed clutch slave cylinder
time to replace both the clutch slave and master cylinder

You need to replace the slave cylinder, it is contaminating the system fluid with rubber seal gunk, this is ruining the new masters. The clutch slave and master should always be done as a pair. This advice comes from 35 years of work experience.

Two possibilties. If you haven't yet replaced the clutch master cylinder there might not be enough pressure to fully engage the clutch. If the master cylinder is full of fluid and has been operating properly until now it could be that you only need to adjust the linkage at the slave cylinder to give a little more throw to the pressure plate. Always try the easiest things first. Good Luck!

on the transmission there is a slave cylinder that works like a brake cylinder, when you apply pressure to the clutch pedal a rod inside the vehicle under the dash pushes into a clutch master cylinder, (almost like a brake master cylinder without the reservoir, as the clutch master cylinder works off the brake master cylinders reservoir) the plunger in the clutch master cylinder applies fluid pressure to the slave cylinder,(located down on the trans near the clutch fork assembly) which projects a piston rod into the clutch fork dis-engaging the clutch. To bleed the clutch slave cylinder locate the bleeder screw on the slave cylinder,break loose so it loosens and tightens easily. Check fluid in brake master cylinder reservoir,fill if needed, while bleeder on the slave cyl is closed have a helper push clutch pedal to floor and back 7-8 times, (At first the clutch might stay at the floor, just pull it up by hand or foot and continue) after several pumps with no rest time push pedal to the floor and hold down with foot pressure, at this time loosen the bleeder on slave untill fluid leaks out, watch for air bubbles, close bleeder and repeat untill there is no sign of air bubbles, (make sure to check fluid in the brake master cylinder and keep fill as needed, do not let fluid get less than 1/2 empty as it might **** air and you will have to start over) If this does not bring clutch to operate then you need to check if slave cylinder is reachig its full extension of push rod or not. If it is not then you will have to replace the clutch master cyl or the clutch slave cyl or both as seals are bad and wont hold pressure. Or you need to inspect the clutch fork,the throw-out bearing, or the pressure plate fingers and clutch plate for failure or broken bent parts. I hope it turns out to be a easy fix on that clutching thing.

You cannot bleed these clutch hydraulics. They are meant to be a pre-bled sealed unit that you buy. You should never replace just the slave or the master. Buy them both and replace them as one unit which is already bled from the factory. Otherwise you will experience what you are describing.

Make sure you install the slave cylinder (into the transmission hole) first and then the master cylinder (pedal side) next and do not hook up the pedal until everything is installed.

If you take the slave out with the pedal attached it will extend the rod and ruin the hydraulics rendering them useless.

Take the top off the master cyl and slowly very slow push in on the clutch and watch for any bubbles comming up.Replace the top and pump pressure and bleed at the master direct by using the lines for bleeders.

check make sure the clutch master cylinder working properly along with slave cylinder. both master and slave don't have to leak fluid to be faulty, the rubber seal inside the unit could be worned and when apply pressure the fluid blow by or seep between the rubber seal causing the the unit not to work properly giving you a weak feel and pressure at the pedal. both unit have to work properly in sync. if one are weak you will have the same issue. clutch should have a good tight feel not sloppy or weak. pressure plate will also play important role, weak pressure plate will also give you a weak pressure feedback from the foot pedal and also will cause the synchronizer in the transmission not to engage and work properly. check this basic item fist before messing with your tranny. clutch master and slave cyc are fairly cheap to fix and replace.

rod activates master clutch cyl and has lost the seals in the master-fluid is migrating back on rod

Replace master cylinder

There is air in the system. The slave cylinder does provide pressure to return the pedal. Check to be sure that you have plenty of fluid in the master cylinder (clutch). Slowly work the pedal back and forth to try and remove air. (This usually works unless you have really lost all fluid. Once the air is remove depress the clutch while in gear. If it does not keep the car from moving then replace the slave and master cylinder. The parts are a little over $100. Hope this helps. I have one in the shop right now as a matter of fact...