cam question

[killerklown]

How tight should the black cap fit on the end of the cam? I'm in the process of changing the chain on my 87 250es. When i have the tension adjuster removed, and the top end cover off, I can hold down on the black end cap, and pull the cam up and down inside it a little under an 1/8th inch? Is this normal, or can this not even happen when all is torqued back down?
Thanks

[oscarmayer]

when it's torqued it shoudl hold it from moving all together.