I installed a new clutch and the master cylinder by the clutch petal as well as a new slave cylinder after bleeding the system when we push the petal the line going to the slave cylinder pops out after checking it it happened 2 more times

 

I just learned the trick a month or so ago.
Pull the line off, install the rubber grommet onto the end of the hard line, there's a little groove for it to fit into, it'll go past the end of the line. Now push the hard line into the slave until you hear a good, LOUD SNAP, that's the plastic retainer that you had to squeeze to remove the line snapping into place.Now install the wire clip and bleed the system and you're good to go. I fought with this for two days and happened on the right person to solve it for me.
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