W204 c220 cdi chain tensioner

[Milner575]

I’m looking to change the timing chain tensioner on my car soon. After looking online I’ve noticed a few different ways of how people have said they’ve done this.

Am I right in thinking I set the ending to rec remove the old and fit the new without the need for anything else? Also should the new tensioner be ‘primed’ with oil before fitting?

Thanks