Tensioner spring issues

Brand new to the forums and I have done hours of research on this to no avail. I have a 2003 Protege5 2.0 and Im in the middle of replacing water pump and timing belt and have an issue with the tensioner spring.

After aligning all my timing marks up and installing the belt and pulleys my manual says to tighten the tensioner bolt and rotate 2 turns on the crank and to loosen the tension bolt and allow it to set tension on the belt. My spring never moves. I've tried rotating the crank with the bolt tightened and loose and the spring never stretches. I have tried putting an Allen key in the tensioner and turned it towards the firewall stretching the spring and putting tension on the belt and then tightening the bolt. The spring goes to it's rest position always.

I turn the crank and the spring never stretches. I know that the spring is what puts tension on the belt. I'm at total loss here. Someone please help
I should mention that the tensioner pulley and spring are brand new
 

pcb

The Diagram Dude
:
2002 MP5
You may have overstretched your spring.
You should measure it to verify.





If the spring is loose and can fall off of the hook pin, then it is stretched and should be replaced.
But if the spring needs to be stretched a little bit to attach it to the hook pin, then it may OK.

The spring has been described as the most important $2 part on the entire car.
It is a critical component.


When I did my timing belt, I was really concerned about stretching my spring, so I attached the spring to the tensioner pulley and loosely tied a string to the other end of the spring and draped the string up over the top of the engine.

Then I could install the belt without stretching the spring.
After the belt was installed, I pulled up on the string and pushed the hook of the spring onto the hook pin with a small screwdriver then removed the string.
 

pcb

The Diagram Dude
:
2002 MP5
After aligning all my timing marks up and installing the belt and pulleys my manual says to tighten the tensioner bolt and rotate 2 turns on the crank and to loosen the tension bolt and allow it to set tension on the belt. My spring never moves.

The tensioner pulley is free-floating even when the bolt is tightened.
So the spring is always applying pressure to the tensioner pulley even with the bolt tightened.

This allows the tensioner pulley to bounce around and absorb vibrations under different driving conditions like quick deceleration after high RPMs.

If the tensioner pulley were to be locked down, you would rip your timing belt to shreds in no time.
 

pcb

The Diagram Dude
:
2002 MP5
Your tensioner pulley and spring are probably working properly.
My last car had a single cam and the tensioner pulley did lock down with the bolt.
The spring was only there to apply proper tension to the timing belt when you lock down the pulley.
Part of periodic maintenance was to loosen the bolt to let the spring take up any slack then retighten the bolt.

Our car is different and has the spring continually applying tension to a free-floating tensioner pulley.

It's kind of crappy design.
Mazda should have that spring built right into the tensioner pulley itself.

The whole spring thing looks like an afterthought.
 
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pcb

The Diagram Dude
:
2002 MP5
Here's a link to a timing belt replacement which you may find helpful.
And a link to the FSM...

 
Not sure I'm following along correctly but I'll add that i just did my timing belt due to my spring breaking and causing the crankshaft to chew teeth up... When i put it back together i hooked the spring on both the hook and the tensioner... But kept the bolt loose so i could easily move the tensioner in it's sort of rocking motion... That helped to get the new belt on... The once the belt was on, tighten the bolt down, then use the Allen key to rotate the tensioner clockwise (toward the front of the car)until the kinda pops over the rocker and it stretches the spring down behind the belt almost... Hope that helps...
 

pcb

The Diagram Dude
:
2002 MP5
Not sure I'm following along correctly
.. But kept the bolt loose so i could easily move the tensioner in it's sort of rocking motion....

That's the whole thing.

The bolt doesn't need to be loose to move the pulley freely.

The pulley is supposed to float freely with the bolt fully tightened down.

If your pulley doesn't float freely when the bolt is tightened, then there is something wrong.

Perhaps some damage when your old spring exploded?
 

pcb

The Diagram Dude
:
2002 MP5
If you go at it again,
Remove the T-Belt, install the tensioner pulley and spring, tighten the bolt down.

The pulley should move freely under the pressure of you pushing on the pulley.

You should only feel the pressure of the spring as you push on the pulley.

If it's binding, then there is something wrong.
 

pcb

The Diagram Dude
:
2002 MP5
... But kept the bolt loose so i could easily move the tensioner in it's sort of rocking motion... That helped to get the new belt on....

When I did my T-belt, I didn't connect my Spring until after I had the belt installed.

That way, I'm not fighting the spring pressure or stretching my spring.
 
Perhaps some damage when your old spring exploded?
I replaced the tensioner as well as all the other parts so there could be no problem... I did it the way I did due to watching multiple videos until I felt like i had a decent plan of attack... This was my first venture into a timing belt replacement...
 
When I did my T-belt, I didn't connect my Spring until after I had the belt installed.

That way, I'm not fighting the spring pressure or stretching my spring.
This is why I left my tensioner bolt loose... so it wasn't applying the tension on the spring or stretching it... I wasn't sure if it would be difficult to get the spring connected after i got the belt on...