1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Head Gasket Replacement on Gen 3 prius

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by prius@noob, May 14, 2022.

  1. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,723
    38,253
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Coolant leak at cylinder 1:

    upload_2022-5-23_12-11-24.png

    Cylinder 1 piston looks exceptionally clean:

    upload_2022-5-23_12-12-27.png

    Also check as best you can that the pistons all come up to the same level at TDC, cylinder 1 in particular would be low if piston arm has bent.

    And if you can get a straight edge and feeler gauges, check the top of block for warpage. The spec's for that are in first attachment (cylinder block warpage), in the first cylinder head head gasket link in my signature.
     
    #21 Mendel Leisk, May 23, 2022
    Last edited: May 23, 2022
    ToyXW, jzchen and prius@noob like this.
  2. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    @Mendel Leisk Thank you for the quick response! Do I need to clean the other cylinders? Or can I clean the surrounding areas with a blade and proceed with putting it back together?

    I did clean egr pipe 2 months ago (will clean again) and planning to clean the EGR cooler too. Is there anything else I need to look into and inspect before I proceed with the installation?
     
  3. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,723
    38,253
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Have you cleaned the intake manifold? I forget. Especially the EGR passages. And the intake ports, though I guess machine shop will do that.. It doesn't hurt to clean the piston tops, but I don't know if it matters. Definitely get the top surface of block clean, gently. Plastic razor blades? And check it for flatness, per my last sentences.

    I think cylinder 2 looks a bit cleaner too, like coolant was just starting to leak into it as well.
     
  4. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Totally forgot about the intake manifold. Will clean that too since it's already off. On my way to the machine shop. I hope the head or pistons aren't warped/bent.

    Is $156 a good deal for the kit?
    0411237254 - Gasket kit, engine valve grind - Genuine Toyota Part
     
  5. ttou68

    ttou68 Active Member

    Joined:
    Sep 9, 2017
    340
    198
    0
    Location:
    40509
    Vehicle:
    2010 Prius
    Model:
    III
    jzchen, Mendel Leisk and prius@noob like this.
  6. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Update: Got the back from the machine shop last Friday and they had to machine the surface, remove carbon deposits from the valves, and it also needed a valve job.

    The manuals state we need to put the gasket and tighten the head bolts within 15 minutes of putting the head back on. I forgot to line up the exhaust outlet and had to remove the head and put it back the second time. Then I realised the torque wrench I was using randomly changed the torque (because it has a stupid locking mechanism). So had to loosed and tighten the bolts again (36lbs, 90 and 45 degree turns)

    Stopped there as I was unsure if I could remove the head and bolts multiple times. Do I need to have it machined again, new gasket or swap out the bolts again?

    Will resume putting it back together once I know what to do.
     
  7. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,723
    38,253
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    The only thing I recall remotely like that was the timing chain cover, after putting the liquid gasket on. And, some of the aftermarket liquid gasket products being used (say by Gasket Masters) have a much longer cure time. But that doesn't ring a bell regarding head gasket; can't see any reason for a time limit there. Gasket Masters cautions to not "slide" the head after putting it on the block with new head gasket, I recall.

    I'm not a mechanic but pretty sure you're fine to just carry on.
     
    prius@noob likes this.
  8. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Thank you So
    Thank you @Mendel Leisk!
    I did not slide it, just picked it up and placed it in an awkward angle to get the exhaust lined up. Noticed some oil leak onto the gasket (I guess they put some oil on after the valve job to lube it?), so i cleaned the surface of the gasket with a rag and proceeded to put the head bolts back on.

    I would like to replace the bolts though just to be sure, is that advisable?

    Update: spoke with my mechanic, it's a go on the new head bolts. Do not want to redo the job if/when the old head bolts break etc.
     
    #28 prius@noob, Jun 6, 2022
    Last edited: Jun 6, 2022
  9. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Question: I've seen a few videos and no one mentioned the torque specs for the cam housing except for one. This video states 22 for the 12mm bolts (yellow ones) and 12 ft-lbs for the 10 mm bolts (black ones). Is that right? Mine is 2011.

    Also can, can someone identify the part in the picture that I broke off? It sits right under the big pipe going into the head. IMG-6408.jpg
     
  10. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Also can, can someone identify the part in the picture that I broke off? It sits right under the big pipe going into the head. View attachment 227120 [/QUOTE]

    Any help here is appreciated!

    @Mendel Leisk I've tightened the head bolts with 36 lbs-ft + 90 + 45 degree turns and the gold and black cam bolts to 20 and 12 lbs-ft torque respectively.
    Proceeding to timing chain tomorrow. If I got the torque values wrong please correct me.
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,723
    38,253
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    [/QUOTE]
    On this page?


    TRANSAXLE ASSY(HEV OR BEV OR FCEV). 2011 Toyota Prius | Toyota


    If you click on the first "head gasket replacement" link in my signature, it takes you to post with a batch of repair manual excerpts. I believe it's this one:

    203170_2010_Toyota_Prius_Repair_Manual_-_Cylinder_Head_Removal.pdf

    That has the torque values.
     
  12. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    On this page?


    TRANSAXLE ASSY(HEV OR BEV OR FCEV). 2011 Toyota Prius | Toyota

    That looks like part number 30900H. Thank you for the link.


    If you click on the first "head gasket replacement" link in my signature, it takes you to post with a batch of repair manual excerpts. I believe it's this one:

    203170_2010_Toyota_Prius_Repair_Manual_-_Cylinder_Head_Removal.pdf

    That has the torque values.[/QUOTE]

    Oh my goodness! I was looking at the pdfs in your links for 2 days now and just realized the torque values are right there on the first page right next to the bolts.

    I hope the car runs after being worked on by an mechanically impaired person like me. :D
     
  13. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,723
    38,253
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    upload_2022-6-8_13-10-20.png

    Yeah I was thinking it might be this, since it's not a bracket hold-down bolt. Not sure. It might have a vent function??

    Check with a dealership parts department too, with your pic, and maybe they can track it down.
     
  14. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Update: Purchased new head bolts and compared the length with old ones. The old head bolts were significantly longer than the new ones (confirmed visually).
    Cleaned the surfaces, applied silicone, put the cam housing and torqued the bolts (Need to remove the shop towel once the timing cover is in place)

    The colored links on chain seems to be going to all the right places, please see pictures. Gasket masters video only mentioned ensuring the links are right next to the markings on both cams and crank, but @ASRDogman mentioned rotating the crank twice (720 degrees) in this post with the timing cover on? Wouldn't it be easier with the timing cover off and using the keyway as a reference?


    1) Am I missing something about the timing chain?
    2) Btw, would be prudent to get a new chain too?

    IMG-6548(2).jpg IMG-6549.jpg IMG-6550.jpg
     
  15. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,908
    3,167
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    I believe the tensioner bolts to the timing cover.
    But you can just push the chain so it doesn't jump a tooth as you turn the crank.
    But, since you do have it set correctly, you should be able to safely install the cover
    and then release the tensioner and rotate the engine twice and all the timing MARKS
    will line up.

     
    jzchen and prius@noob like this.
  16. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III

    Ah shoot... totally forgot about the tensioner.

    Sorry to be such a bother, but just to see if I got this right: Put the timing cover on, rotate the crankshaft bolt 720 degrees clockwise, come back up and check the rectangle notch and the extended notch on the cams are back where they were pre-rotation?
     
  17. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,908
    3,167
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    You're not being a pain, you want to make sure you're doing it correctly the first time. (y)
    Yes, all 3 notches should line up. Just as they are BEFORE you rotate it, and the colored
    links are on there marks....
    Make sure you keep the chain where the tensioner is pressed so it doesn't jump.
    If you have someone to help, that would be good. Rotate slowly.


     
    Mendel Leisk, prius@noob and jzchen like this.
  18. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III

    Thank you for your patience, and your guidance is greatly appreciated!
    I though the color links are supposed to jump a tooth every rotation and would take about 70 rotations to line up with the notches on cams according to this post.
    Maybe I'm reading too much into this, will put the timing cover and tensioner on tomorrow and see for myself.

    It would've been much easier if gasket masters included this in their video lol, or someone did.
     
  19. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,908
    3,167
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    The colored links are ONLY there for initial installation to make it easier.
    I've done several timing chains and haven't seen this before.


     
  20. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
    55
    16
    1
    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    D6269CAB-4F22-433F-936D-5386AF9F2BBC.jpeg 05A30A26-14E4-4FA1-9C9F-2E133D1750D7.jpeg 80B47494-ADF2-4A8B-89FB-25C21EAF46F7.jpeg 26871C26-3B2B-4E67-83A9-5AE0A2992F8C.jpeg
    Decided to take your advice and proceed with timing cover installation today.

    after cleaning the components and getting the surface ready for silicone, I noticed the crankshaft seal is a non reusable item in @Mendel Leisk repair manuals. It too a few hours to locate and drive to purchase the item locally.

    i had a little difficulty getting the links to line up and sit flush on the gear teeth. Almost like the chain shrunk just a bit. One of the three marked links was 1/3rd off their teeth from sitting flush. Tinkered with the swing arms and got it to sit almost right and decide timing chair tensioner might take care of the rest.

    Decided to “mock” put on the timing cover and harmonic balancer to check the marking is at 0 degrees on timing cover (denotes TDC of the cylinders?). The marking is off. Like way off. Attached pictures after mock putting on tuning cover.

    Did i completely screw up? How do I go from here?