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Found a Hole - Is my Engine or Tranny Kaput?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by QuarterMileAAT, Feb 5, 2022.

  1. QuarterMileAAT

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    Finallly getting around to do the head gasket repair thanks to warmer weather. Went to remove the splash panel and find a hole near what I believe is the bell housing(?). There is significant coolant in that area. There is some coolant in areas just a little higher up in the engine compartment. But I don't see where it can be running down from much higher up in the engine compartment.

    Did I develop a crack in my engine and is it caput? Or worse, is the a transmission side crack?


    Hole_.JPG

    Here is a zoomed in shot of the hole.

    Hole_Close.JPG
     
  2. PriusCamper

    PriusCamper Senior Member

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    Any signs of damage anywhere else? That's a very odd shape for a hole created from impact or failure... What happens when you stick something in there, does it keep going up or stops? Also how are your coolant and transmission fluid levels currently?
     
  3. ChapmanF

    ChapmanF Senior Member

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    That looks more like a weep hole provided on purpose, though I have not just now rushed out to lie in the snow and compare mine.

    Is your coolant noticeably low in either the engine system or the inverter/tranny system?

    A cracked engine block could conceivably leak coolant into that area, and the tranny has a flat, O-ringed, sheet metal donut in the same area, directing coolant around MG1 (seen in some Weber U videos), which I guess could also be a source of a leak.

    But I think if my reservoir levels were not of concern, I'd probably just wipe the pink off and make a note to kind of watch it.
     
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  4. QuarterMileAAT

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    Sticking a small screw driver in there keeps going quite deep before it touches something. Drained the coolant and a significant amount came out, but the tank was almost empty. Didn't check tranny fluid levels.

    My reservoir was empty. Still, a significant amount of coolant drained out from the petcock. Inverter levels are good. I can't see damage, but of course it is hard to inspect. Hoping the coolant leak is from a hose at best. From the blown HG at worst. I am just wondering if I should go forward with the HG repair. Makes no sense to do so if the engine/tranny is kaput.

    Can anyone confirm if that hole is manufactured in?
     
  5. PriusGuy32

    PriusGuy32 Prius Driver Extraordinaire

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    I just googled "Gen 3 Prius transmission fluid change" to be able to get pictures from someone else changing their transmission fluid just to see that area; that divit/drain hole? is in fact there on other Gen 3 Priuses. That is not a chip or crack, it is designed to be there.
     
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  6. QuarterMileAAT

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    Thanks @PriusGuy32 . I'll proceed then. There is significant fluid leak. Hope it isn't a cracked engine.
     
  7. PriusCamper

    PriusCamper Senior Member

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    Put more coolant in and send us pics or video of where it's coming out...
     
  8. QuarterMileAAT

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    I am too far into the disassembly now to pour in more coolant. I'll just keep an eye out for where the leakage could have occurred as I go. I suspect it is from the HG as I can't see any coolant hoses going in through the back of the engine. I guess I should say, I am hoping. It could very well be a crack in the lower engine.

    Anyhooo, this thread is a wrap as we know that hole is manufactured in now. My progress will follow through on this thread.
     
  9. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    I know what that little divot is:

    @Ragingfit noticed, and employed it, when separating his engine from transaxle. He speculated it was for just that purpose, and used it with a narrow cold-chisel: a few taps to brake the bond. it's noted in one of his videos on the 4th gen engine swap, pinned at top of Prius v modifications forum (technically appropriate location, but hard to find).

    Bottom line: it was like that from the factory.
     
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  10. Ragingfit

    Ragingfit Active Member

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  11. PriusCamper

    PriusCamper Senior Member

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    Lol, although we do tend to continue chatting after the thread is wrapped up...
     
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  12. QuarterMileAAT

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    All good. Seeing it in person however, it isn't quite regular. But then again, there was enough regularity to make you think it couldn't randomly chip off in such a shape. Also, there was a ton of coolant around it in my situation. So I thought I'd ask the pro's.
     
  13. TMR-JWAP

    TMR-JWAP Senior Member

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    This sure is similar to the other recent thread where the guy is concerned about a trans leak. His photos show the same tell tale drain/weep hole. He was trying to figure out if it was oil/transfluid or coolant.