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Leaking red fluid Gen II 103,000 miles

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by mulin, Feb 3, 2014.

  1. mulin

    mulin Junior Member

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    Help! A month or so ago I saw a few drops of red fluid on the garage floor under my 2008 Prius... but then nothing until yesterday when I discovered a small puddle. This has been such a great car, I've done nothing to it other than change the oil, tires, engine/cabin filters, bulbs, and 12 volt battery. At 103,000 miles, I was ready to find a mechanic to have the coolant drained/refilled and transaxle fluid changed as recommended. Then this. I took it to a local mechanic who comes well recommended and personally owns a Prius. Looking under the car, he says it's "coolant" but can't find a leak and says he must take the transaxle apart... maybe have to replace it!! I called the dealer service dept who told me on the phone that he's never had to change a Prius transmission and I should bring it by for a $60 second opinion.

    Has someone else experienced leaking red fluid on a Gen II? Suggestions for my independent mechanic before he dismantles the whole thing?!
     
  2. jdcollins5

    jdcollins5 Senior Member

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    Is the fluid dark red or pink? The transaxle fluid is dark red and the coolant is pink.

    If dark red it could be something as simple as an axle seal leak. If it is pink the most likely suspect would be the engine coolant pump leaking.

    Your mechanic should have been able to determne this without taking anything apart, other than maybe the engine undercover. I would definitely get a second opinion.

    Where are you in NC?
     
  3. mulin

    mulin Junior Member

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    Pink Fluid -- not dark red. Thank you for clarifying this. He has not yet taken anything apart... Should he be able to see the pump leaking without dismantling? (I'm in Asheville.)
     
  4. jdcollins5

    jdcollins5 Senior Member

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    Yes. He should be able to look at the back side of the pulley on the front of the engine and see evidence of the pink. With this amount he should be able to see it on the AC compressor also. He may have to look closely and may have to use a mirror or something but he should be able to see it. The most likely suspect is the engine coolant pump which is a minor replacement.

    It could possibly be leaking from the underside of the transaxle but you should be able to see this on the engine undercover.

    Check your coolant reservoirs, both the engine and the inverter/transaxle. If one of these is low this could be the indication of which one is leaking.
     
  5. jadziasman

    jadziasman Prius owner emeritus

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    Never mind. Already answered more quickly than I can type and edit.
     
  6. frodoz737

    frodoz737 Top Wrench

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    "I took it to a local mechanic who comes well recommended and personally owns a Prius. Looking under the car, he says it's "coolant" but can't find a leak and says he must take the transaxle apart... maybe have to replace it!!"

    Do not ever go to this mechanic again...not even for tire pressures.
     
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  7. frodoz737

    frodoz737 Top Wrench

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    oops duplicate
     
  8. mulin

    mulin Junior Member

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    Thanks. I'll bring this info to him tomorrow! ...and let you know! Is there any chance this leak is related to the recall on the inverter water pump? (I was told mine was fine and it was not replaced.)
     
  9. jadziasman

    jadziasman Prius owner emeritus

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    No. The inverter water pump is on the driver's side. The gasoline engine water pump is on the front passenger's side.

    At the end of the post below is a youtube video showing where the gas engine water pump is located.

    ICE water pump replacement - Gen II | PriusChat
     
  10. mulin

    mulin Junior Member

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    Unfortunately I still have no diagnosis of this leak. My mechanic appreciated the comments above that I brought to him, but he says the leak is at the BACK of the engine -- in a tiny space between the engine and the transaxle, so he can not tell which direction its coming from until he takes (something?) off to get a closer look. He wants to determine if it's leaking from the engine or the transaxle.

    My new observations: the dime-sized drop is located 25" back from the front bumper, 26" to the right of the inside of the driver's tire, and 28" from the inside of the passenger tire.

    I see that the fluid in the inverter coolant reservoir is at the "low" mark. Could I just open it up and add coolant every now and then to make up for the slow drip? (Or are dire warnings about air in the lines worth my attention?!)

    Does a leak of pink fluid at the back almost center of the engine offer any diagnostic information to you? Other suggestions?
     
  11. frodoz737

    frodoz737 Top Wrench

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    If you pull off all the lower covers, give it a good belly wash, do an idle run and short road trip, you should be able to localize the leak easily...but that's easy to say from here.
     
  12. jdenenberg

    jdenenberg EE Professor

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  13. Patrick Wong

    Patrick Wong DIY Enthusiast

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    My suggestion is that you buy a gallon of Toyota Super Long Life coolant from your local Toyota dealer's parts dept. When the car is cold, fill the inverter coolant reservoir to the full mark. Fill the engine coolant reservoir to the full line. Remove the black plastic cover over the radiator, remove the radiator cap, and fill the radiator neck to the top, if needed.

    Now you have a baseline where you are starting from full. Drive the car for the next few days and see where the leak is coming from, by looking at the fluid levels when the car is cold. Then at least you'll know whether the engine or the inverter/transaxle is the problem. You can also see how long it takes for the leak to be reflected in a noticeable drop in coolant level.

    Once the leak has been narrowed down to engine or inverter/transaxle, it will be easier for the mechanic to figure out the precise source of the leak.

    A dime-sized leak doesn't sound like much, but it does appear that the leak amount is increasing over time according to your OP. So it would be good to figure out the source of the leak and fix it.
     
  14. a11m1ghty

    a11m1ghty New Member

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    I had a similar issue. It was a $10 fix and 10 minutes of my time. It was the thermostat seal that presses against the coolant cap. Feel underneath it with your fingers, if you should feel the wetness, replace your thermostat.

    It drove me crazy, the pools of red on the floor in my garage. I almost spent $500+ for a mechanical water pump replacement and fluid flush at a local Toyota Dealership.

    Needless to say, no more pools. The pools made it hard to pinpoint where the leak came from. I thought it was the rear too. It was in the front instead.
     
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  15. jadziasman

    jadziasman Prius owner emeritus

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    Hmm, bad gasket on the thermostat, eh?

    Another thing I'll need to inspect periodically, thanks a11m1ghty.
     
  16. shsmani

    shsmani New Member

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    I think I have a similar problem, I lifted the car and looked underneath, the leak was coming off from the tube connected to the engine coolant reservoir cap. Is it normal for the coolant fluid to leak off the tube attached to the Engine coolant reservoir cap? Is is the same problem as the thermostat seal against the coolant cap, if yes is it the cap on the reservoir? I am certain it is off that pipe because all the underside of the pipes had the pink residue, not so much the top side. Appears the leak is falling on the fan blades and the fan blades splattering it all over. I do see some residue on the water pump as well, so I think that needs to be replaced as well but before that I wanted to isolate additional leaks.

    Appreciate any help.

    Thanks
    Mani