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Idler pulley replacement (I need help)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by maali, May 8, 2015.

  1. maali

    maali New Member

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    Hello,

    I would really appreciate if someone can help me I have been a series of troubles. This is how it began during my car Prius 2005 (130000 KM ) routine service at Toyota they told me to change to drive belt as it was worn out (there was no screeching or any other annoying sounds)

    I decided to do it myself with help from a friend who is a part time car mechanic, so we manged to loosen the pulley and took out the old belt and put on the new one and tightened it now when we started the car and then turn off the engine and touched the idler pulley it was very hot we barely could touch it for 2 sec.

    My question is that is it normal for the pulley to become hot ? or can it be that we over tight it ? (we loosen the tension-er a bit but still it gets hot)

    Then I went further bought a new pulley and its same result that still gets hot ? may be its normal would appreciate your input on this.

    BR
     
    #1 maali, May 8, 2015
  2. JC91006

    JC91006 Senior Member

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    The pulley is just for the water pump. Which part is getting hot?
     
    #2 JC91006, May 8, 2015
  3. maali

    maali New Member

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    Its the Idler pulley that becomes hot. so the tension-er and the bolt and pulley metal itself.
    Adding the picture as attachment to be clear its the part marked in red cricle
     

    Attached Files:

    #3 maali, May 8, 2015
  4. JC91006

    JC91006 Senior Member

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    this is part of the engine compartment, I'm not understanding why you would think it wouldn't be hot?

    This thread will give you all the necessary info on the replacement, I think you know this.

    Belt change how-to with photos | PriusChat

    Here is the tension info

    The adjustment procedure is to loosen the nut on the pulley, then turn the adjusting bolt to achieve the desired belt tension. Tightening torque on the pulley nut is 30 ft-lb.

    The desired belt tension is reached by pressing in the middle of the belt's longest run with 22 lbs pressure, deflection of a new belt should be between 0.35 to 0.47 inches. A used belt should show deflection from 0.43 to 0.59 inches.
     
    #4 JC91006, May 8, 2015
  5. maali

    maali New Member

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    Thanks for your help and pardon my limited knowledge :)
    Can you tell me the signs of a worn (need replacement idler pulley ?) this part is off course connected to engine but we thought that as there is a bearing inside pulley it should not become hot or at-least the pulley metal should not become hot.

    So you say its normal for it to become hot ? and nothing to worry about may be I can return the pulley and save some cost :(
     
    #5 maali, May 8, 2015
  6. JC91006

    JC91006 Senior Member

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    I can't remember touching this part to confirm if it gets hot or not. I would think if you suspected a bad idler pulley and replaced it, and still get the same result. It probably is normal. Just make sure the belt tension is correct and not too tight
     
    #6 JC91006, May 8, 2015
  7. maali

    maali New Member

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    ok cool thanks.

    any prius owners can you please check this and help ?
     
    #7 maali, May 8, 2015
  8. valde3

    valde3 Senior Member

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    If you start cold engine and let it idle until engine stops pulley shouldn’t be very hot. That pulley has 2 bolts in it. Adjustment bolt to adjust belt tension and tightening bolt. Maybe you left the tightening bolt lose and belt tension is then causing the pulley to a bit out of alignments? Maybe your belt is way too tight? (Gen 2) Prius belt should be very lose compared to other cars. Belt only drives the water pump.
     
    #8 valde3, May 8, 2015
  9. maali

    maali New Member

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    Thanks for your reply, I will check if it is too tight or loose.

    Can you let me know the signs of a worn out pulley ?
     
    #9 maali, May 8, 2015
  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    A worn out pulley will produce noise and may wobble.

    Did you tighten the nut which is coaxial to the pulley, to ~30 ft.-lb torque? When you push on the longest length of the belt with 22 lb of pressure, does the belt deflect ~0.4 inches? If yes to both, then you should be OK.
     
    #10 Patrick Wong, May 8, 2015
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