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Inverter & transaxle coolant cross contamination

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by blacktouring, Dec 9, 2010.

  1. blacktouring

    blacktouring Junior Member

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    My 07 Prius is leaking transaxel fluid into the inverter cooling system. Transaxel fluid is sweating through the inverter coolant hoses. Before my taking ownership of this vehicle, it had previously been in a front end collision (that’s a whole other story). Anyhow – if I replace the radiator, should that take care of this problem? Are there any other ways these two cooling fluids could become cross contaminated?
     
  2. dogfriend

    dogfriend Human - Animal Hybrid

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    Re: Inverter & transaxel coolant cross conatimation

    I think replacing the radiator would be a waste of time and money. Because there is no external ATF cooler for the transaxle, the only way you could be getting ATF in the coolant would be an internal case crack in the transaxle.
     
  3. Hal W

    Hal W New Member

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    Re: Inverter & transaxel coolant cross conatimation

    Or someone poured it in by mistake? H
     
  4. blacktouring

    blacktouring Junior Member

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    Re: Inverter & transaxel coolant cross conatimation

    That's what I thought originally - I had the inverter fluid flushed, but it happened again. The Prius Tech at my local dealership (DHC Toyota Torrance CA), thought that it may be happening in the radiator - hence my original question. He stated that both the inverter and transaxel have coolers built into the radiator and as a result, may be the source of the cross contamination. But from dogfriend's response, it's sounding like this might not be the case.

    Dogfriend - what would be involved in fixing the transaxel case? This car has less than 20K and despite it's issues, I actually like it more than my Gen III / ii.
     
  5. edthefox5

    edthefox5 Senior Member

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    Re: Inverter & transaxel coolant cross conatimation

    Wow that Prius Tech is clueless. Beware using him. The Inverter coolant loop is independant of the radiator. The rad is used exclusively for the engine.

    The Inverter coolant is circulated through a very small area of the transaxle. It seems you may have a very rare leak in that area between the coolant area and the internal transaxle. Caused by that accident.

    If it was me I would jack the car up as best and as safely as I could
    and get under there with a flashlight & look at the trans area closely. You may see impact evidence. That would save alot of time and head scratching.
    Smashed cvt and it must be replaced.

    Lots of posters have done it themselves using used cvt's. And its not a huge job for a competent shop. Some posters have done it themselves at home. At the dealer the cost would be very very high. But lots of used cvts out there.

    I see 4 right now on eBay but wrong years.
    Just an example but there out there. You might be able to find one locally in a salvage yard. Going rate is $500 to $1000.
     
  6. edthefox5

    edthefox5 Senior Member

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  7. blacktouring

    blacktouring Junior Member

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    Re: Inverter & transaxel coolant cross conatimation

    Thanks for the input - I do have to say that I am wary of buying such a major mechanical component used over ebay, even if the seller has 100% positive feedback. The Prius I'm posting about I found on ebay - seller w/100% feedback. I ended up, by his recommendation to "save money", buying the car outside of ebay. He listed the car as clear title, which technically it had (if an accident is never reported, it does not come up in a carfax), but I later found out (after having a warning light come on, from this very issue) that it had been in a major front end collision.

    I'm now in a legal struggle and being that he's out of state (I'm in CA, he's in Ohio) and that I lack the funds and time to take him on in court, it's looking like I'm somewhat stuck.
     
  8. edthefox5

    edthefox5 Senior Member

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    Re: Inverter & transaxel coolant cross conatimation

    Thats unfortunate. Its a common story we have seen many times
    here at PC.

    As far as buying used you may not have a choice as retail on a new cvt is :

    https://www.toyotapartscenter.net/2007toyotaPriusparts.html

    plus tax & freight which could round out to around $3400. Plus indie installation. Now your pushing $4000.


    Of course if the dealer was installing this part even the part's price that you already know would be more. Why?....no good reason.
    And a dealer labor install would be obscene. I would expect a $5000
    bill with a new dealer installed CVT.

    But I have been doing ebay since 1999 and usually if the seller is a business and has 100% and has been in business for a few years there ok. And whatever you do USE PAYPAL!!!! If you use Paypal the seller knows he cannot burn you. The only thing you would need to do is get that trans installed quick. You can't come back 3 months later and bitch.

    If you don't use Paypal you will get screwed.Thats my motto.

    But, you can also use eBay as a price point standard and then find one locally in a salvage yard. At least you will know what the going price is.

    I have been burned maybe 5 times in 10 years on eBay but have used Paypal and they have got a refund for me every time without exception.

    If it was me I would have no problem with a used cvt if I talked to the guy and got its history. There a pretty bullet proof transmission ...unless you crash into them.

    But before all this you need to take a peek at the trans yourself. See if its all busted up under there.
     
  9. dogfriend

    dogfriend Human - Animal Hybrid

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    Re: Inverter & transaxel coolant cross conatimation

    I agree that a used transaxle would be the best bet. I would do a through inspection for other damage. You wouldn't want to spend a couple of grand on a transaxle and then find other damage to the steering rack or subframe.

    Good luck.
     
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  10. blacktouring

    blacktouring Junior Member

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    Re: Inverter & transaxel coolant cross conatimation

    Thanks everyone! Yes I've certainly learned by PP/ebay lesson!
     
  11. uart

    uart Senior Member

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    Re: Inverter & transaxel coolant cross conatimation

    If there's really transaxle fluid getting into the inverter coolant loop then wouldn't there also be coolant getting into the transaxle ATF. I would think this would show up as being very apparent if you drained the ATF and take a look.
     
  12. dogfriend

    dogfriend Human - Animal Hybrid

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    Re: Inverter & transaxel coolant cross conatimation

    True, and if there is a lot of coolant in there it will compromise the effectiveness of the ATF (i.e. coolant isn't a good lubricant)
     
  13. Hal W

    Hal W New Member

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    Re: Inverter & transaxel coolant cross conatimation

    blacktouring, how much oil are you getting into transaxle cooling system? If its not a great amount I would just change the anti-freeze every few mths. Will it go that long without filling the tank? H
     
  14. edthefox5

    edthefox5 Senior Member

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    Re: Inverter & transaxel coolant cross conatimation


    I agree. Its a very tough trans. That trans would run on castor oil I bet!

    For now he seems to be at least mobile with it. But your right unless he plans on pulling the new cvt trigger soon he should immed. dump the trans fluid and see how bad it is. A new cvt fluid change might buy a whole lot of time.
    In the meantime check all the bone yards locally within 50 miles radius as there may be a good deal on a cvt.
     
  15. bsoft

    bsoft New Member

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    Re: Inverter & transaxel coolant cross conatimation

    There's a good lesson here: if anyone on eBay EVER asks you to do a "side deal", RUN. They are in violation of their agreement with eBay just for offering, and you have zero protection if you go through with it.

    Standard practice on eBay is to complete the auction (or buy-it-now) on eBay and use PayPal. Any deviation from that should immediately arouse suspicion.

    I have used eBay many times in the last 10 years and I have never gotten burned. If you pay using PayPal you have a lot of protection. Sellers hate PayPal because they almost always side with the buyer, regardless of the facts. You can't even leave negative feedback for buyers anymore, so sellers have basically no way to retaliate.
     
  16. blacktouring

    blacktouring Junior Member

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    Re: Inverter & transaxel coolant cross conatimation

    I spoke with an independent mechanic that I trust and he also stated that it could be the radiator being the point of cross contamination. I asked him this same question. He said the pressure of the transaxel coolant is higher than that of the radiator and because of this, it wouldn't take on engine coolant. He said this is a common phenomenon in non hybrid cars that have trans coolers integrated into the radiator core.

    But from what others are saying, the Gen 2 Pruis does not have an integrated trans cooler in the radiator - I'm going to look for myself tomorrow. But if it does, I may try replacing the radiator first to see if that solves the problem before replacing the transaxel.
     
  17. edthefox5

    edthefox5 Senior Member

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    Re: Inverter & transaxel coolant cross conatimation

    I think in my previous post I mispoke as I did not fully understand the issue. Inverter coolant is in the bottom of the radiator but separate from that rad. There separate loops but just like most automatic cars the Inverter coolant is in the bottom.The Inverter coolant is air cooled by the fan just like the rad coolant.

    But I'm still not sure why you suspect there's trans fluid in the coolant? What exactly leads you to believe there's trans fluid in the Inverter coolant?

    A cross contamination of the radiator engine coolant and the Inverter coolant in the separate bottom partition of the radiator will not result in trans fluid in the Inverter coolant. There will just be mixed engine and Inverter coolant. And would probably disturb the cooling efficiency of both systems.

    But neither has anything to do with the trans fluid.

    If you still think there's rad to inverter coolant cross contamination happening drain the rad engine coolant and while draining that keep an eye on the Inverter tank (the plastic container to the left of the Inverter). Open the cap of that Inverter coolant tank while draining the rad and see if it reacts at all to the draining engine coolant....bubbles...lowered level..any disturbance. You should see none. That will cost you $10 of coolant.

    Thats about all you can do yourself without specialized tools to check the pressurization of the radiator. Any indie shop can do that in about 10 minutes for probably $30-50.

    But bottom line the rad has nothing to do with trans fluid.

    The only way trans fluid can be induced into the Inverter coolant loop is by a fractured coolant area in the trans leaking trans fluid into the Inverter coolant loop.

    To get that question out of the way just dump the trans fluid and look at it. Should be nice and red just like automatic trans fluid.
    That will take 4 quarts of Toyota WS. Thats $40. And while under there check the trans real careful and see if there any damage like I said before. You will see 2 black rubber hoses go to the trans. Thats the coolant area under those hoses. Check that area.

    Both of these tests will not cost more than $50. And both alot easier than replacing the radiator and are basic maintenance anyway.

    I have not seen rad to inverter coolant contamination ever mentioned on PC in almost 4 years of being on here.