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Head gasket likely, advice/confirmation?

Discussion in 'Gen 3 Prius Main Forum' started by Dagoba, Jul 13, 2024 at 12:37 PM.

  1. Dagoba

    Dagoba Junior Member

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    2011 with just over 200k miles, did an EGR cleaning at 180k miles, which is roughly when we took ownership of car.

    My girlfriend was about to take the car 1000 miles away the other day, and on the day before her trip we went to do a short drive in town and the car had a rough start, shaking. I shut it down immediately and checked the coolant, was right where it should be so I started it again and it shook for a second and smoothed out. I was worried it was water atop the pistons burning off, but with no coolant loss I thought maybe it was something else. Started the next morning with no shaking, so figured it was something one-off. Also have heard about rough starts if the car is shut down after the engine being run for just a few seconds, but I thought that was only in cold months?

    Anywho fast forward, she’s about 600 miles away now and calls and says that the coolant light came on, and that it was low, like to the bottom of the tank. ^$&#. I started preparing to rent a tow dolly and go get the thing, she was caravanning luckily with a couple of friends, and could get a ride with them. Before that though wanted to confirm that it was the HG, so I had them buy one of the combustion gas tester kits, which came back negative for combustion gases in the coolant. So I had them buy some Bars stop leak, and do the procedure. That did seem to do the trick, after the first running cycle it lost only a little, and then stayed at the top ofter that for the next 400 miles. Crisis averted (or rather pushed down the road).

    So with the rough start that morning, coolant loss, and the fact that it was fine after the stop leak I’m fairly certain it’s the HG. The negative combustion gas result is mostly what has me wavering. There were no external coolant leaks either. I suppose the only option that I can think of was that there was a leak at the water pump (only thinking about this now) and it was temporarily fixed by the stop leak. The Bars that we used I believe has both solids, and the silicate product that reacts with heat to seal a combustion leak. They said that there was a little bit of water under the car but it was hot and she was using a/c, so I figured the little bit of water was condensate. In hindsight I should have had them dab it with a white towel.

    Thoughts?

    Edit: she still has to drive back home in a few days which will be a little bit of a white-knuckle couple of days, I’m wondering if I should be preparing to assemble parts for a HG job, I would likely just buy a new or reman head and check the block. I read through a thread that talks about the rods becoming bent, and I don’t want to do all the work only to find out it was in vain shortly thereafter. How does one measure or determine the shape of the bottom end? Compare piston heights at top of stroke with head off? Compression test for rings? Except can’t do a compression test with an HG leak.
     
    #1 Dagoba, Jul 13, 2024 at 12:37 PM
    Last edited: Jul 13, 2024 at 12:45 PM
  2. Tombukt2

    Tombukt2 Senior Member

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    Me personally I have learned my lesson with this engine and model and I wouldn't be preparing to do any such thing get me $2,02,500 out of the vehicle if it's possible and make arrangements I know it's a cute sexy looking car but now that should have worn off. Or be prepared to put a few grand in the mess and pray and hope with proper looking checking the deck height and all of this stuff It could work a while or it could not and you have this money vaporized so if you have money to vaporize and it wouldn't really affect you then by all means play the game that's what it's all about
     
  3. Dagoba

    Dagoba Junior Member

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    Is that a lot or a little?

    So in essence - these cars are a sexy money-vaporizing hot mess that likes to play games.
     
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  4. bisco

    bisco cookie crumbler

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    that's pretty much the size of it, although i would say you got your moneys worth at 200k, if you haven't done the engine, battery or brake actuator.
    there are plenty of threads here from people who have replaced their head gasket, swapped engines and even put in a gen 4.
     
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  5. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    Sounds like you did the EGR angioplasty about 50,000 miles too late and it weakened the HG.

    Since you're able to DIY the head replacement I'd be tempted by this.
    If the car makes a 1,000 mile return hop on a bars-leak repaired bottom end then you're probably OK there, plus you have to consider the cost AND hassle delta between replacing the head and the motor.
    If both are small for you then a JDM motor might be your way to go.
    If replacing the bottom is beyond your situation then that makes the head replacement the least sucky option.
    You're looking at a 13-year-old car with 200k miles - BUT......
    You live in the PN-Dubbs and I'm betting that gas, used cars, candy bars, EVERYTHING is more expensive than it is in other places - so that also is a factor.

    Good Luck!

    Be different......
    Check back in and let us know how it shakes out.

    Oops.
    Bad metaphor?
     
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  6. Tombukt2

    Tombukt2 Senior Member

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    I tried to get me 2000 or 2500 out of what's left of the vehicle and move on me personally before I have five or six grand in the necessary repairs to a car that I can't see from here may not be worth three. That's all I'm saying I would probably want to start bowing out now before I start playing coolant loss games with engines that have no room for mistakes machining or any of it that's how they get this lightweight high gas mileage etc an old 350 V8 has plenty of metal to machine and straighten out and remove to bring things back in to qualifying specifications a Toyota 2ZZ doesn't have that luxury It's design It is part of the grand production process as it moves forward I guess
     
  7. Tombukt2

    Tombukt2 Senior Member

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    Yes and you've done well at 200k chalk it up and be good about it No worries If you start playing these thousand-dollar games and antics you're going to wind up or you don't want to be so maybe not do that hell for two grand you can buy a pretty good running generation too yeah for some people that may be a step backwards In reality I don't see how anyone could think that except looking with their eyes It's not as new and if that's where we are then I'll bow out and we're good I'm here for the long haul my friend I am not interested in fly by night vehicles that'll be here for a few minutes so that I can play initial d games or whatever not at all All of my cars make $500,000 miles except one or two and they were like Chevrolets or something no Oldsmobile
     
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  8. Tombukt2

    Tombukt2 Senior Member

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    The only car in my life right now sitting just at 70 years old that has ever cost me any money that I would even breathe or talk about is a Gen 3 Prius I promise you I have the paperwork whatever all of my other vehicles going back Toyota 40 some odd years never anything like the 2013 Prius Persona which was just two owner car from oursman dealership network in Virginia DC area and the two owners lived across the street from each other they were good friends The car was never beat on nothing boringly driven to DC to work and parked in a parking garage and driven back home with two or three occupants. All other Toyota's I loan since the KE Corolla of the late '60s early '70s all the way up until that 13 Persona made 400k or better looked decent doing it and cost me almost nothing It was ridiculous That's why I say in the 40 years I've been fiddle farting around with cars I haven't paid any money and I'm not looking to start now I have friends of mine that have spent hundreds of thousands of dollars on car nonsense over the same 40 years doing whatever doesn't really matter and not with super expensive cars either regular run of the mill boring get to work type stuff
     
  9. ASRDogman

    ASRDogman Senior Member

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    Putting the pretend head gasket sealer was your downfall.
    Heavy cleaning of the radiator, heater core, water pump(or replacing), replacing the
    thermostat, cleaning out the small passages. Hopefully the head gasket is not warped.

    What type of coolant did she use? Using the incorrect coolant could cause it to jell....
    Then it doesn't flow. Then seizing the engine. Hopefully, she used Toyota 50/50 coolant.

    Since it just started leaking, once it gets over the initial knocking, by shutting the engine off
    a few times, driving will likely be okay as long as she doesn't wait long enough for the engine
    to cool and fluid leak into the cylinder.

     
  10. Eddie25

    Eddie25 Active Member

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    Almost definitely the head gasket. Did the check engine light ever come on? I don't think a negative combustion gas test is super reliable on these cars. Stop leak will probably get her home but you'll have to deal with that if you do the job as it has potential to clog other things up.

    If you have the time and space (and tools), pull it apart and get a proper straight edge to check it and go from there. That's what I did and was able to get the job done for about $350 including the $70 straight edge (I had already done the water pump and thermostat recently though, which you'll want to replace most likely especially having done the stop leak). If it fails again it's not a huge deal, but if it doesn't I saved a ton and I'm personally willing to take that gamble.

    I don't see why you'd get a new head and not a new block though. I would do it the other way around based on my experience (car burns oil, but the head was in great shape).
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    How’d it look; any pictures?
     
  12. Tombukt2

    Tombukt2 Senior Member

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    Well at 200k when you look behind the valves which you can't see unless you knock the keepers in the springs off and let them fall out and see all the build up on the back that gets blasted off and they get ground and then he seats look pitted or messed up they get dinked in and new ones pressed in however it works in the particular head that's all lubed up all springs are checked everything's compressed put back together of course the head's been shaved decked milled whichever and all that is is they drop the head on a big belt sander table and hold it down until they have a nice sand pattern on it pick it up flip it over look at it drop a straight edge over it and that's it modern heads have no room for real milling.
     
  13. bettergolf

    bettergolf Active Member

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    He didn't get 200k out of it...he got roughly 20k if you read his post.
     
  14. Tombukt2

    Tombukt2 Senior Member

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    I thought the car had 200K on it total My bad if it didn't
     
  15. rjparker

    rjparker Tu Humilde Sirviente

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    Don’t waver- it’s normal on these engines with a hg leak. The only diagnostic that would have saved your girlfriend would have been a Borescope inspection. Too late now.

    Obviously your mistake was letting her go on a trip when the shaking had started. An empty reservoir means it’s now an advanced late stage hg failure- it’s even possible the guy who sold it to your girlfriend 20k miles ago already hid the failure with previous sealer.

    The latest sealer confirms the hg but as dogman says you now have a lot to clean up or better yet you should change the engine.

    Odds are good it’s an oil burner as well and needs rings, pistons. rebuilt head, cleaned or new intake and a complete gasket set to support the timing chain cover etc. Assuming the block or head is not warped or the cylinders are not scored.

    A so called “low mile” complete JDM used engine previously operated in Japan is about $1200 plus install. Probably as easy as a good head gasket job on your engine. But there is no real way to verify the “low miles” of a JDM engine. Still a decent option with some risk.
    JDM Engine 4 Views.jpeg


    A rebuilt engine shipped from a company like Hybridpit in socal is another option that is likely to get you 100-150k miles without engine issues.
    Prius gen3 hybrid pit rebuild ebay.jpeg
    Doing nothing because it runs smooth now is a prescription for a hole in the block down the road.



    It’s interesting Gasketmasters just published a video recommending preemptive hg replacements.
    From 2022
     
    #15 rjparker, Jul 13, 2024 at 7:03 PM
    Last edited: Jul 13, 2024 at 7:18 PM
  16. bettergolf

    bettergolf Active Member

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    It does...he bought it at 180k so he got 20k out of it...someone else got the 180k.
     
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  17. Dagoba

    Dagoba Junior Member

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    Doing the EGR cleaning at a higher mileage weakens the HG? How so?


    You know it’s funny, part of the reason we moved here is because it was a lower cost of living than the bay area CA. So I guess it’s all relative. Also, got 2 snickers for something like $1.50 the other day which felt like a win.

    What I’m gathering from everyone’s experience here is that with this mileage my best use of money if we are to keep the car (which is certainly the plan) then dropping in a JDM or similar is a gamble a few notches safer than only doing the head. Only doing the head, might have to go in again and be out even more money, only twice.

    I have some somewhere I’ll see if I can find them. It was sooty for sure, but not fully blocked. It’s my first prius so I don’t know what the normal amount of buildup would have been.

    Car doesn’t burn much oil, I wanna say maybe 1/2 qt. between 5k oil changes, at a max. At least I don’t think that’s too much? Thinking new head since it’s good practice to do new valves etc, and the tendency for heads to warp at higher mileages? But that’s why I’m here asking, if I’m going the wrong direction I’d like the schooling. WP and thermostat would be a definite, as well as radiator flush and egr flush.

    I would normally never use that product, but this was a pinch. She used the Zerex asian car coolant, which is what I had in there since replacing it. At this point kinda just need to cross fingers that she gets back home, and I can deal with the mess then.

    Is your memory that good or are you just one helluva sleuth? Seems I was thinking of a preemptive replacement 2 years ago! News to me.

    Appreciate all of everyone’s input! I suppose I’m not certain which direction I’ll go, but I will be considering a JDM. I remember reading about the 4th gen swaps, it’s tempting but I’ll have to think about that some more. Knowing that the battery and brake booster are all gonna be the same age it seems less tempting to spend more money than less on this car. We got it for $4750 in pretty good condition a couple years back, when prii turned seemingly to gold once gas prices went sky high, and it’s been trouble free until this…
     
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  18. rjparker

    rjparker Tu Humilde Sirviente

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    That is not excessive by Toyota standards but a good engine will burn no obvious oil in 5,000 miles. Mine burned no obvious oil for the first 100,000. Some is burned even in these best cases but fuel dilution and condensation make up the difference.
     
  19. Dagoba

    Dagoba Junior Member

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    What I’d mainly wonder is with a history of minimal oil burning is a head swap a likelier success in my case.
     
  20. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    I figure the plugged EGR cooler weakened the HG.
    Not really your fault, since it sounds like you jumped on the cleaning fairly quickly after you got the car.
    5k oil changes are a wise move and I wouldn't be bothered by the 1/4q burn rate.

    I feel ya.
    I have a brother who is doing 20-to-life behind the Tinsel Curtain.
    He married a local and they punched out three kids and now he's trapped.
    PNW is cheaper.....
    Keeping the car is ABSOLUTELY going to be cheaper.
    Putting a JDM engine into the car and maintaining it properly will be the most expensive fix but you'll (probably) only have to do it once - and if the GF regularly does 1,000 mile jaunts in the car then it makes a 'once and done' repair more attractive.
    Spending $300 on just replacing the HG and verifying that the head isn't warped might also be an attractive option.
    You can scope the bottom and do some leak-down tests after to make sure that the gasket is still gasketing.

    I figure that the HG is like a fuse.
    They fail to protect more expensive things, which made all kinds of sense back in the days when a trip to an ER and a Mechanic did not result in the same number of zeroes in the bill.
    If I had the tools, space, time, etc to replace the HG, and I knew that the engine wasn't overheated then that would be an very attractive option.

    Gas is expensive up there, but it's NOT that expensive!!
    What you're really trying to avoid is getting another car - because then you're either having to buy new, finance new, insure new, and pay taxes on new - or get another used car.
    This would place you squarely where you are now minus the 20,000 miles of knowing your G3 and the knowledge that you actually like the car - warts and all.

    The Prius is a little like your GF.
    Cheaper to keep her.
     
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