Let's talk about belt tensioners!

[IUP99snake]

I'm due for a new tensioner on my car. Mine's starting to make noises, and it's noticeably weaker than the last time I changed a belt...

I'd love to get the ThumpRRR Racing billet tensioner, but for $395, I'm going to have to take a pass on it for now. Are there any other aftermarket tensioners in the $100 range?

If not, I'm going to end up getting a stock style replacement again...But there are a bunch of places that sell a stock style tensioner such as Advance Auto, Auto Zone, Pep Boys, Napa, the Ford Dealership, etc... etc....

I'm pretty sure that the production tolerances and spring rates differ among all of the tensioners you can get from these places, despite their claim to be "OE Quality" or whatever.

Has anyone had better or worse luck with any specific tensioner from any of these places? Any place I should avoid?

Better yet, has anyone done a test on these tensioners? It would be interesting to buy 2 or 3 tensioners from each place and test them with a torque wrench to see what the differences are... Keep the strongest one and return the rest..

Homer

 

[DSG2003Mach1]

IMHO, the Thump tensioner is bullshit for what they charge.

I bought mine second hand and I dunno if it was missing the mounting bolt or I just didnt see it but they wouldnt even sell me a replacement. They finally got me the specs and the bolt is waaaay too long, took several stacked washers to shim it out (so I figured out the right length and got a shorter one).

I didnt notice until I installed it and had a god awful noise that the pulley they supply rubs the body of the tensioner because their tolerances are off (its not a bearing issue), Ive seen pictures of several others doing it too. If you try to shim it off with the smallest shim you can find that will fit, the pulley will then hit the timing cover. We machined it down around 15 thousandths on both sides (it could have fit a 10 rib belt with room to spare before).

According to another member (that also had the rubbing issue) the way the single bolt tensioner is setup its not quite clocked correctly, he claims Thump was aware when he spoke to them but apparently they havent changed anything as far as I know

 

[IUP99snake]

IMHO, the Thump tensioner is bullshit for what they charge.

I bought mine second hand and I dunno if it was missing the mounting bolt or I just didnt see it but they wouldnt even sell me a replacement. They finally got me the specs and the bolt is waaaay too long, took several stacked washers to shim it out (so I figured out the right length and got a shorter one).

I didnt notice until I installed it and had a god awful noise that the pulley they supply rubs the body of the tensioner because their tolerances are off (its not a bearing issue), Ive seen pictures of several others doing it too. If you try to shim it off with the smallest shim you can find that will fit, the pulley will then hit the timing cover. We machined it down around 15 thousandths on both sides (it could have fit a 10 rib belt with room to spare before).

According to another member (that also had the rubbing issue) the way the single bolt tensioner is setup its not quite clocked correctly, he claims Thump was aware when he spoke to them but apparently they havent changed anything as far as I know

Wtf??? Thanks for the heads up. I can't believe they can sell something with those types of issues. Are you sure it wasn't designed for a different application? Maybe they didn't realize there were differences between the car it was originally designed on and every other car out there..

Yea mines starting to squeak real bad and it's throwing belts much more easily than usual.

 

[01yellercobra]

I have the Thumprr tensioner and I haven't had major issues with it. The mounting bolt was too long but that was easily remedied by a trip to the hardware store. I had to go anyway since I needed bolts for the 8 rib swap.

If you have the 3 bolt tensioner check out UPR's replacement tensioner.

 

[DSG2003Mach1]

Wtf??? Thanks for the heads up. I can't believe they can sell something with those types of issues. Are you sure it wasn't designed for a different application? Maybe they didn't realize there were differences between the car it was originally designed on and every other car out there..

Yea mines starting to squeak real bad and it's throwing belts much more easily than usual.

Ive never seen anything to indicate that there is any difference between any single bolt tensioner timing cover from year to year or anything. The pulley to cover clearance would be ok if the tensioner arm/mounting point was square and I wasnt trying to stop it from rubbing the arm on the bottom side (and its not even belt tension, You can make it rub turning the pulley in your hand)