My parents have a 94 Accord EX-R (Canadian model). Lately, the clutch pedal feels no resistance. I've replaced the clutch fluid and bleed the system. It's almost fine for a week or so and then it goes back to really soft and sometimes the pedal stays right at the floor.

Would this be the master or the slave cylinder gone bad? I can't see any leaks.

Is there a way to test this?

Also, how to remove the master clutch cylinder? I've done the slave on my civic before so I know.