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Should I replace the tensioner pulley when I replace the belt?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Silver 2008, Jul 17, 2015.

  1. Silver 2008

    Silver 2008 Junior Member

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    I have a service manual for every vehicle I own except my Prius. I can't remember now why, but I think it was too expensive to purchase at the time. Anyway... I am replacing the engine belt for the first time (70K miles) and was wondering if it is recommended to also replace the tensioner pulley?

    If anyone does have a service manual, can you share what the spec is for re-tightening the tensioner?

    And if anyone knows where to get a service manual at a price that won't have me clutching at my heart, let me know that too.

    Thanks in advance.

    Mike
     
    #1 Silver 2008, Jul 17, 2015
  2. valde3

    valde3 Senior Member

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    You shouldn’t need to replace the tensioner pulley. You can easily test it when the belt is off by just spinning it. Tensioner should have super long life but it (and also the life of water pump and belt) can be reduced a lot if belt is too tight.

    Belt deflection with force of 10kg or 22lb (center of longest run (between crank pulley and tensioner pulley) should be 9…12mm or 0.35…0.47in with new belt. Nut in the center of pulley is tightened to 40Nm or 30ftlb. But it can be very tight so use good quality 6-point socket to loosen it.
     
    #2 valde3, Jul 17, 2015
  3. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    For an 08?
    I probably wouldn't but that's me, and I don't have a G2 manual nor do I know what they recommend, so this answer is a SWAG!!

    Here's my thing:
    It's working and it's only got 70,000 miles on it.
    Leave it alone.

    There's a much greater chance that you'll get an inferior replacement part or cause another problem by replacing the pulley.
    At 70K for an 08, you're probably not replacing the belt because the old one broke.

    Reassess the pulley thing the next time that you proactively replace the belt.

    Good Luck!

    Let us know what you decide.
     
    #3 ETC(SS), Jul 17, 2015
  4. Silver 2008

    Silver 2008 Junior Member

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    Thanks valde3. I will order just the belt then. I think I only have 6-point sockets in my set, so that won't be an issue. There is no torque spec for tightening the tension bolt itself? I will probably experiment with that to see how much torque needs to be applied to achieve the proper deflection.

    In the service manual for my wife's Maxima, there is a torque spec in inch-pounds for the tensioning bolt which puts the deflection perfectly in spec.

    I found the 3-volume service manual online for $411. Now it is clear to me why I did not buy one when the car was new. If anyone has a source to get the manuals cheaper, please let me know.

    Mike
     
    #4 Silver 2008, Jul 17, 2015
  5. Silver 2008

    Silver 2008 Junior Member

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    No, it isn't broken, just cracking/fraying. I will give the pulley a spin when I get the belt off. If it spins freely, I will just put the belt on and check it in another 70K when I put the next belt on.

    Thanks for the help.

    Mike
     
    #5 Silver 2008, Jul 17, 2015
  6. jdenenberg

    jdenenberg EE Professor

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    Mike,

    Send me a PM and I'll provide a link to download the Gen2 (06-09) repair manual from my web site. It is a large zip archive of pdfs.

    JeffD
     
    #6 jdenenberg, Jul 17, 2015
    SFPrius2006 and ETC(SS) like this.
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    No spec.

    It is not necessary to replace the pulley unless your inspection reveals a problem. It is easy enough to replace the pulley when it shows signs that the bearing is starting to fail (such as getting noisy.)
     
    #7 Patrick Wong, Jul 17, 2015
    Last edited: Jul 17, 2015
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