Idler pulley reinstallation issue?

You may need to loosen the engine mounts and move the engine back slightly, if you upload a short video or image so I can see what you are trying to do it will help. Also, you may have to have a helper hold the engine back using a large pry bar which will move slightly in the rubber engine mounts. When you say idler pulley do you mean the belt tensioner? Here is an image below so we can be on the same page.

Thank you for the response I went ahead and just bought the tensioner and pulley and just replaced the whole thing greatly appreciate it. The problem was there's a center bolt 8mm on the housing and if there's a lot of gunk it's hard to tell it's a bolt this made it easier to take the housing out if that helps anyone out there running into the same nuisance.

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