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Has anyone had to replace the timing chain tensioner gasket?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Higgins909, Aug 2, 2023.

  1. Higgins909

    Higgins909 Member

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    I'm wanting to clean up my engine nice and good and and try to spot where this leak is coming from. I thought it was the head gasket but after trying to search this leak, it might be the tensioner gasket. It seems there is 2 styles as well. 1 is a crush gasket and then the other is a big O ring. I'm not sure if it's getting worse or not. It's definitely as dirty as it's ever been. (old photo)

    It seems this is a semi common problem for toyota 1.8 engines. According to a earlier post of mine, it's been going on before 193k. I wonder what is a typical mileage/age.

    IMG_20230225_21480765.jpg
     
    #1 Higgins909, Aug 2, 2023
  2. The Critic

    The Critic Resident Critic

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    Don’t waste your time, it isn’t leaking from where you suspect. It is leaking from the circled T-joints, which requires a timing cover reseal to correct.
     

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    #2 The Critic, Aug 2, 2023
  3. Higgins909

    Higgins909 Member

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    That's disappointing if so. I don't think it's leaking on the intake side of engine. Is this more of a engine oil pressure or engine rpm problem? You don't think I could nicely jerry rig it with some silicone caulk or something?
     
    #3 Higgins909, Aug 2, 2023
  4. ASRDogman

    ASRDogman Senior Member

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    You need to gunk the engine really well, wash it off really well.
    Then drive it, and check it often.
    Oil pressure switch and valve cover gaskets can cause 90+% of the leaks.
    Both inexpensive and easy to replace.

    But if you clean it well, and check it often, you'll be able to SEE where it's leaking from.

     
    #4 ASRDogman, Aug 2, 2023
  5. The Critic

    The Critic Resident Critic

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    It is clearly leaking from where the head gasket, block and timing cover come together. You can see the head gasket in the picture.
     
    #5 The Critic, Aug 2, 2023
  6. rjparker

    rjparker Tu Humilde Sirviente

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    IMG_2504.jpeg IMG_2505.jpeg IMG_2506.jpeg Good timing chain pic.jpeg
     

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    #6 rjparker, Aug 2, 2023
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  7. Tombukt2

    Tombukt2 Senior Member

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    My 10 is leaking from.oil switch for months .
     
    #7 Tombukt2, Aug 2, 2023
  8. Paladain55

    Paladain55 Active Member

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    Try cleaning up the oil from the block and swapping to high mileage oil. It will usually swell the seals enough to stop the weep.
     
    #8 Paladain55, Aug 3, 2023
  9. Higgins909

    Higgins909 Member

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    I need to clean it up still. Trying to figure out the best/cheap cleaner to do that. I've been using some 5w30 Syn blend high mileage oil as my top-off oil. I've only got about 2,400 miles on this oil change so far. Not sure how long I would have to wait, to expect results with mixed oils. My main reason for trying a higher weight oil again was to measure oil loss when towing but my HVB is still on order and can't tow.

    I was thinking, what if I didn't take it all apart and just put a safe blob of RTV silicone on the B, T joint? Right next to the tensioner. I'm kinda wondering about ease of removal if its a failed attempt.
     
    #9 Higgins909, Aug 5, 2023
  10. rjparker

    rjparker Tu Humilde Sirviente

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    Take the wiper assembly off like you were changing the plugs and use a pressure washer.

    There are six block to block joints under the timing chain cover that create leak channels. Three on each side. Extra sealant is required during assembly of the timing chain cover and still they often leak with time. See post 6 above. Even if you somehow globbed on enough two part industrial sealant on one or two accessible locations you still have the others.
     
    #10 rjparker, Aug 5, 2023
  11. Paladain55

    Paladain55 Active Member

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    Careful with the pressure washer. Rough on seals.
    I have compared 0w-40 and 0w-20 and they didn't make a noticeable difference on weep or consumption. Any high mileage oil will have a similar formulation. I just use Supertech 0w-20 as i have been, but swapped to the high mileage version. Full swelling i would imagine a couple months. Project farm on youtube has some interesting videos on the high mileage oils as well.
     
    #11 Paladain55, Aug 8, 2023
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