[tristancary]

Hi all,
I am working on replacing the alternator in our 2011 3 2.5 and can't for the life of me get the belt back on. I am not sure where the belt tensioner is on the car and any help would be appreciated. Attaching some photos for some guidance.

 

[thatsp23kid]

Make sure you are placing the belt the original way else it won't fit. You have to get someone else to hold the belt tensioner back so you can fit it around all pulleys, the same way you got it off. I was unable to find a diagram for you but look around for "2011 Mazda 3 Serpentine Belt diagram".

 

[Akmnhg5A]

Watch this video. At 2:20 you'll see the tensioner and how to move it.

 

[theblooms]

That's your tensioner right there. It pull towards the front of the car to loosen.

I've found the easiest way to put the belt on is leave the upper idler pulley nearest the font of the car off, pull the tensioner, then slip the belt over that idler.

Works every time.

 

[theblooms]

Here is your belt diagram, except you don't have the power steering pump, you have an idler at the top. Same exact routing though.