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Belt Driven Water Pump Replacement?

Discussion in 'Gen 2 Prius Main Forum' started by jimolson, Aug 28, 2023.

  1. jimolson

    jimolson Member

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    Besides the pump and drive belt (which is a given) what additional pump-related parts should I replace during this job?

    Vehicle is a 2006 Prius with 200k miles. The repair is focused on the belt-driven water pump only. I've already replaced the electric water pumps.

    Is the water pump equipped with an idler pulley and belt tensioner?
     
    Tombukt2 likes this.
  2. Tombukt2

    Tombukt2 Senior Member

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    It's a basic mechanical water pump with a clutch fixed to it like an air conditioning compressor would have on a regular car so the water pump can be turned off not spinning when the car software says so I won't be touching mine which is 300,000 right now until it leaks from the weep hole starts making a racket because the front bearing's gone or something I will not touch mine until it fails I've had a belt replaced or I put a new belt on gates and that's been the only thing I've touched I don't think the clutch will wear out on this water pump duty like it would on an air conditioning compressor It's not pulling or holding very much of a load to spin a water pump so essentially it should last forever until the bearing fails inside the pump and that's when I'll fix it I would imagine mine's going to probably last to 500 plus thousand than the car will be finished or close to it so I probably won't even get to change it I have a couple other generation twos in the same boat won't touch until they break it's not a maintenance item per se.
     
  3. jimolson

    jimolson Member

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    Tom, is the electric clutch on the water pump pulley or the drive pulley on the crank? And is there a tensioner?
     
  4. ChapmanF

    ChapmanF Senior Member

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    I've never seen any sort of water pump clutch on a Prius.

    The Gen 1 and Gen 2 1NZ engines have a belt, a water pump with a pulley, and an idler you can use to adjust the tension. The idler adjustment tends to get stuck with rust and make people work harder than they were expecting.

    On Gen 1, the belt also drives an A/C compressor, and that has a clutch, but the water pump just sits there and pumps.
     
  5. Tombukt2

    Tombukt2 Senior Member

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    Yeah I had to go out and look at the one I put the belt on and the tensioners just on the bracket right above the pump I just thought that might be a clutch on the front of the pump because of the backwards pulley that doesn't have any belt grooves but nope it's just a regular water pump and pumped all the time and I'm not going to touch it except put a belt on it every 70,000 till it croaks.
     
  6. jimolson

    jimolson Member

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    Thanks guys. I'll buy the idler pulley, a pump and a drive belt.