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2004 Prius Belt Tensioner

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by balmeral, Dec 6, 2015.

  1. balmeral

    balmeral Junior Member

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    Today I went to change the belt on my 2004 Prius. I loosened the top pulley bolt, and then took out the tensioner bolt completely. The pulley did not slide down to allow me to take of the belt. I ended up just taking off the pulley. Is there any recommended grease that I could put on the tension mechanism to prevent it from sticking in the future?

    Thanks!
     
    #1 balmeral, Dec 6, 2015
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I would just replace the idler pulley if there is any concern about its condition. They don't cost very much.

    But if you must reuse it, I suggest removing it, cleaning the tensioning mechanism, and using a minimal amount of white lithium grease to lubricate. Obviously you do not want any lubricant to get anywhere near the serpentine belt.
     
    #2 Patrick Wong, Dec 6, 2015
  3. balmeral

    balmeral Junior Member

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    Thanks for the response Patrick. I don't think there is anything wrong with the idler pulley itself. It spins freely with no grinding or halting. When I took off the pulley, a bolt/post remained. This bolt/post is what the idler pulley sits on, and also what the tension bolt screws in to when adding tension to the belt. This bolt should slide up and down, and this is where the rusting/sticking is occurring. I will try adding a small amount of white lithium grease.
     
    #3 balmeral, Dec 6, 2015
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Please take some photos so that we can see the extent of the rust. I had not noticed that problem when I replaced the engine coolant pump on my 2004 and 2007 - of course those cars are not driven in areas with winter salt on the roads.
     
    #4 Patrick Wong, Dec 6, 2015
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  5. kenoarto

    kenoarto Senior Member

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    How long did it take you replace your coolant pump?
     
    #5 kenoarto, Dec 6, 2015
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Probably 2.5 - 3 hours or so. Allow plenty of time to get the air out of the engine coolant loop.
    How to replace engine coolant pump and thermostat | PriusChat

    The last photo in my referenced post shows what the engine bracket looks like with the idler pulley removed.
     
    #6 Patrick Wong, Dec 6, 2015
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  7. edthefox5

    edthefox5 Senior Member

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    I just did mine last weekend. The tensioner bolt the one you can clearly see does not release tension until you loosen up the pulley bolt.
    Take the pulley off and pay attention to the orientation of the pully & washer assy on the back side of it. Then take out the tension bolt and the tension receiver assy and clean it all up. Put the pully back on with the bolt loose and then put the tensioner bolt on just a few threads.
    Snake the belt on and over the bottom pully and the tensioner pulley. Tighten the tensioner bolt until its just a little snug. Just enough not to come off. Tighten the pulley bolt as that "stakes" the tensioner assy.

    Put the car in INSPECTION mode and let the engine run for about 10 minutes. Look at the belt closely while its running with a flashlight and see how it looks. This 10 minute engine run will break the belt in a little. A new belt is extremely stiff. If you tighten that belt up brand new it will be pretty loose in about a thousand miles.Then loosen back up the pulley bolt and adjust tension on the belt and then tighten the pulley bolt back up.
    Check it again in a few hundred miles.
     
    #7 edthefox5, Dec 7, 2015
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  8. bisco

    bisco cookie crumbler

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    great write up ed, thank you.(y)
     
    #8 bisco, Dec 7, 2015
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