the bolt threads were more triangler than round, whats up with that? reason?

 

I know this is an oddball question, just wondering if anyone ever noticed this

 

Hmmmmm.......maybe I'll have to take my tensioner off and check this out.

 

its the tensioner pulley bolt.

 

And you're talking about the threads on that bolt right? Now you got me curious, if it wasn't almost 12 oclock I'd go out and check it right now.

 

yep, the threads on that bolt. (they are 10mm 1.5 pitch threads)

a regular bolt screws right in, but the tensioner bolts threads are triangler

 

We use some triangular threaded bolts in our seat assemblies. They are called tri-lobe and they are fine-tread, self-tapping. I don't know if this is the case with the tensioner bolts or not as I haven't looked at them.

 

Is there a lot of thread engagement? Maybe it has something to do with the threads on a standard bolt galling or seizing. Less thread engagement = less thread contact area = less opportunity for a stuck bolt. Where are the engineers when you need them?