timing belt tensioner: new vs old style

[nosyt]

sorry if this has been gone over i did search with no clear answer

are there any benefits to either style tensioner? my motor was built with the new style and it seems to weeping slightly (wet around the pin) but i have a full old style and bracket available to me.

so do i spend the money and replace the new style tensioner or just covert the motor back to the old style

[vrg3]

For what it's worth, I feel like I've heard of more new-style tensioners failing than the old-style. That might have to do with the fact that newer Subarus have longer belt replacement intervals though. I don't know if the changes happened at the same time or not.

Is the old style setup new or used? If it's new, I'd definitely use that. If it's used, well, then it's less clear -- I guess in that case I'd just use whichever setup it was cheaper to buy a new tensioner for, and use a new tensioner.

[Alphius]

Vikash is right. The newer style tensioner is much more prone to failure. I would use the old style even if it is used, as long as it has been stored compressed and isn't seeping any fluid.

[Legacy777]

I personally don't care for the new style tensioner setup. It doesn't seem to keep the belt tensioned as well. I think Subaru has compensated for this by adding a cover around the crank gear. I seem to recall the tensioner on the new Legacy having a tiny bit of weeping coming from it.

http://main.experiencetherave.com/subar ... G_6574.JPG

[nosyt]

yea ive decided to go with the old style one and since ive gone to an sti oil pump i picked up the crank gear cover as well just as a safety. my local parts guy at the dealership said those covers only come on manual transmission cars probably to help belt jump while bashing through the gears

[Legacy777]

That's interesting to know the covers are only on the MT cars.

[Deride]

New style ones had some major failure issues. A Subaru tech friend of mine told me that there are colored dots on the newer style ones and if the dot is blue to throw it away. You want the one with the GREEN dot. Another friend of mine said to replace them with the timing belt and never to re-use them. The older style ones are really FTW, as I have never heard of any issues and I have re-used many of them myself.

[ciper]

The belt covers on MT cars are to keep the belt from jumping teeth when the engine is off and the car is moved in gear (or popping the clutch to start it). Brand new cars would come off the boat/truck with a check engine light from rocking back and forth in gear. Not a problem on automatics obviously.

[Legacy777]

Interesting. Good to know.

[SiCkSTi04]

stick with the old style, I've heard too many stories where people confuse a failing newer style timing belt tensioner with piston slap, valves etc. http://youtu.be/2J0vgN_nJbs

[mike-tracy]

Subaru redesigned the "newer" style again: there's an additional small pulley on the edge of the tensioner, as seen in the pic above. Vica put one on his motor - I believe it requires a different style bracket than the "newer" one mentioned above.


Pre-redesign for reference:



Personal note on the crank sprocket belt stay: I put one on my old Outback when I did a timing change. After about 15k miles I took it off due to the belt rubbing on it! Swapped in a new belt of course. I realize you can adjust it up and down a little, but IMO it wasn't worth sacrificing another belt (or my valves!) to find out.

[ciper]

If you have a choice between the two new styles try not to get the one with the small pulley. They constantly fail because they are spinning twice as fast and the bearings are also much smaller (think skateboard bearings)

If you don't have a vice and need to compress the tensioner you can use a pair of chain vice grips like so


Remember that the old style must always remain horizontal and the two new styles must always remain vertical or they will be damaged.