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Oil Pump Chain Timing Marks

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by TwoPriusInTenn, Dec 26, 2020.

  1. TwoPriusInTenn

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    2012, 3rd Gen - Does anyone have a diagram or picture of the correct sprocket and timing chain mark placement for the oil pump when engine is tdc? My timing chain skipped a link when I replaced it also throwing off the oil pump off.

    Thank you.
     

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  2. ChapmanF

    ChapmanF Senior Member

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    [​IMG]

    That said, I've been wondering for years just how you would tell when your oil timing is off...
     
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  3. TwoPriusInTenn

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    Thank you. I was wondering as if it makes any difference in how the oil pump is timed. I guess those marks are there for a reason so I might as well use them. Thanks again!
     
  4. jerrymildred

    jerrymildred Senior Member

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    Timing for an oil pump? Hooda thunk it?
     
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  5. ChapmanF

    ChapmanF Senior Member

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    It honestly makes me a bit curious. A quick Google for "oil pump timing" nets a lot of pages about Mitsubishi 4G63 engines, which have weighted balance shafts to be kept in the proper phase with the crankshaft, and a timing mark on the oil pump sprocket that is part of that scheme.

    But as far as I know, our 2ZR oil pump is just a shallow little pump there, sitting at the front of the engine. I suppose they still could have tweaked its weight somehow for some sort of vibration-canceling effect. Does the New Car Features manual say anything about it? Anybody?
     
  6. TwoPriusInTenn

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    The shaft for the sprocket on the oil pump is flat on one side to correspond with the inside of the shaft housing on sprocket and timing dot. So, I guess it makes a difference.
     
  7. ChapmanF

    ChapmanF Senior Member

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    So the manual would suggest. For inquiring minds, the question is still (in the absence of Mitsubishi-esque balance shafts or the like), what difference?
     
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