2nd blown head gasket, what gives?

Discussion in 'Gen 2 Prius Main Forum' started by oil_burner, Dec 28, 2019.

  1. oil_burner

    oil_burner Active Member

    Joined:
    Feb 26, 2017
    249
    123
    0
    Location:
    Canada
    Vehicle:
    2006 Prius
    at 272k miles my 2007 blew a head gasket. Plumes of white sweet smelling smoking coming out of the exhaust but I did not really notice the coolant level dropping nor was there milkshake in the oil. Since the engine was burning 1qt of oil every 1000 miles I decided it was time anyway.

    I bought a junkyard engine with 125k miles and swapped it in the summer time. Genuine Toyota coolant was used. It drove fine and oil consumption was low. I put 7000 miles on it and over the last month I have noticed stronger and stronger coolant odor in the exhaust. Today after driving it harder for about 30 min and walking around the back of the car, I'm noticing again thick plumes of very steamy white exhaust, very strongly sweet like burning coolant. STILL no trace of milkshake in the oil and the engine coolant reservoir under the hood remains at medium. The car feels down in power.

    Any idea what is going on? Why am I blowing so many head gaskets? I shudder to think of putting another engine into the Prius, this will probably be the kiss of death. Is there any other area of possible coolant intrusion into the intake? I know the throttle body has a small coolant line routed through it but I believe it is cast into the aluminum and impossible to leak at this area?
     
  2. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    10,570
    14,401
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    What’s the coolant level in the radiator:whistle:?

    Do you ever have any dash lights?

    Does the heat work correctly?

    Ever swapped out the water pump or thermostat?

    When the last engine was on its way out, did you use any head sealing materials, like Bars Leak or Blue Devil?

    Good luck and keep us posted (y).
     
    SFO and dig4dirt like this.
  3. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    4,307
    1,643
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Maybe it's just bad luck... But it is a lower mileage engine, so why not just replace the head gasket on this if a thorough diagnosis indicates that will solve the problem?
     
  4. oil_burner

    oil_burner Active Member

    Joined:
    Feb 26, 2017
    249
    123
    0
    Location:
    Canada
    Vehicle:
    2006 Prius
    coolant level in rad is full up to the cap. Heat works fine, no to pump/thermostat was with the "new" engine. I did use bars leak on the last engine but thoroughly flushed the radiator and coolant recovery bottle with Prestone radiator flush and distilled water until no flakes were present.

    light is on for p0420 due to using an aftermarket cat, also p0300, 301, 304 multiple misfire on cylinders 1,4. The car sputters at idle and idles rough. I changed plugs last week which helped for about one week, now they are likely fouled again.

    Replace the HG would probably cost $1000 labor, no point on doing it on a vehicle with 280k miles on the body and the car is only worth about $1000 at this point at auction. Nevermind the host of other issues that could pop up soon like brake accumulator, traction battery, etc.
     
    bisco likes this.
  5. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    4,307
    1,643
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Yeah... I see your point... But if you're DIY oriented and can do the work on your own there's probably more than 100K miles more you can get out of the car and engine. In general DIY on Gen2 Prius makes for a car where you can keep it going for a long times. But if you have to pay a shop to do the work, it's probably not going make sense to spend that kind of money.
     
  6. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    4,307
    1,643
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    With all those existing error codes the whole system is going to be hard to maintain as well... Just drive it till it dies and you might be surprised how long it will keep going! Even the best running older Gen2 Prius run rough at idle... Things might be ok with this one for a while longer.
     
  7. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    8,408
    3,833
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Sounds like you are overheating the engine. You will never know since there's no temp gauge. Most likely the Bars stuff has clogged the rad and you are not getting good cooling. Are both rad hoses the same temp?

    Buy a Scan gauge and watch the engine temp. Without that you will never know if you got all the air out of the coolant and it could be running really hot all the time. That's about the only thing that blows head gaskets is heat the little aluminum head cant take it it tends to warp and then the gasket fails.
     
  8. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    4,307
    1,643
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    This is how I ended up with my first Prius... I had a '92 Subaru I bought w/100K miles on it for $3K in 2002 and by by 2007 at 230K miles the engine went bad and so I had a rebuilt engine that was rebuilt by the folks who use them in airplanes. An incredible engine... But in the interest of saving money I didn't replace any of the cooling system parts and a couple leaky radio hose incident later at 300K in 2011 all that heat warped the heads and it was was dead and there was no longer rebuildable replacement heads for that old Subaru engine type. Replacing the cooling system with everything brand new was my biggest regret. Of course switching from Subaru to Prius was the biggest benefit of this failing.
     
    edthefox5 likes this.
  9. oil_burner

    oil_burner Active Member

    Joined:
    Feb 26, 2017
    249
    123
    0
    Location:
    Canada
    Vehicle:
    2006 Prius
    I have the torque app always on, this year I didn't tape my grill up and the engine barely gets to 160 with trips around town. Like I said I was very careful to flush through each hose so I know none are clogged, and I definitely burped every bit of air out of the system. It is dead of winter here and something like 25 degrees out. If the engine were to overheat it would have done so in the summer.

    I am wondering if the blown HG is actually from oil consumption clogging up the cat and causing too much cylinder pressure.
     
  10. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    8,408
    3,833
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    We have seen a few clogged cats on this site.
     
    PriusCamper likes this.
  11. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    4,307
    1,643
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Yeah... I'd look into this one... Good idea...
     
Loading...