I know, this is an odd request. The previous owner of my Miata has recently replaced this belt but it had been too loose. As a result it would squeek when I ran ac and skip under load and have a rough idle. I opened the hood to tighten the belt, noticed the bolt was ever so slightly bent. I loosened the the Bracket with the female threads that the bolt screws into, and started to tighten the tensioner bolt. A few turns later the bend got way worse and as I tightened I felt the bolt give way. It half snapped in place. I immediately stopped what I was doing and cinched everything back up. Belt still isn’t tight to spec, but tight enough to eliminate all those problems (YAY). However I need to correct this problem before I end up being left stranded. I could try and match up the bolt at a local hardware store but I figured with all the part outs and everything going on someone here would have one to sell. I’m not sure how it got bent to begin with though.. (I’m thinking he over cranked on the bracket with the female threads after “tightening” the belt, causing bolt to bend at the fitting)so thought and opinions on that are welcome! Picture

.. hopefully!

 

The threaded part is not square to the flange the bolt goes through. You need to loosen that nut, thread in the new bolt, and then tighten back up.

Hardware store is your best bet for a new bolt.

 

Did you loosens the bolt that's hidden by the power steering pump pulley? You need to loosen that before you can adjust the tension.

 

Thats likely what I’ll end up doing

 

Yes I did!

 

I've bent the bolt before, tired and forgot to loosen the others.

as far as replacing the bolt, just grab a bolt of the same length and thead from the hardware store.
High tensile preferably, but it's not the end of the world if it isnt.

 

I have used Home Depot bolts for this purpose before. You don't really need it to be as long as the original bolt either, if you can't get one that long from HD. Pretty sure I didn't.