I'm not an engineer (and don't play one on TV ), but I know that any belt has some give & take as it is runs, and they eventually stretch. A fixed-tension setup like the P600B uses cannot address either of these issues. Look at the stuff used in cars- my 1965 & 1966 Corvairs have fixed-tension idlers (with metal "keepers" by the fan & idler pulleys- when you rev the motor, you can see the belt move) for the relatively narrow V-belts (as did most cars of that era), yet all my newer vehicles have spring-loaded tensioners for the wider serpentine belts. One of the "upgrades" to the Corvair belt system developed in the aftermarket is a spring to make the tensioner spring-loaded. Since the ATI uses a wide belt, one would think a spring loaded tensioner would be the way to go. If nothing else, they make belt changes a lot easier .

I find it hard to believe that with all the engineering that went into this unit, that ATI didn't provide a spring loaded tensioner.

 

I thought my tensioner was spring loaded I know that you tension it, and lock it down but it still moves slightly if pressed on.

 

I never got that far with mine, but there is no spring in it or with it.

 

No the stock tensioner that comes with ATI's are fixed.

 

Why are there two halves to the tensioner and one moves? If you pry up on the tensioner the 1/2 still moves providing constant tension on the belt. I can move it just like the tensioners for the serpentine belt on my Camaro and Mustang and they are both spring loaded.

 

If I remember correctly when you set the tension on the tensioer there are 3 fastners the prevent the tensioner from moving. Are making sure they are tight? From what I remember the fixed tensioner should not move at all.

 

the tensioner is internally spring loaded it has three springs inside of the two halves

 

I have 90% of the spring tensioner install done. Here is a link to page 6 of my webpage that deals with this project. I'll post back in a few months if all goes well.

 

There is one 1/2 inch bolt that goes through the back of the bracket and locks down the tensioner. But once it is locked down and properly tensioned, the pulley can move to adjust for slackness.