Coolant disappearing and can't find where

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by Carsten, Jan 22, 2025.

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  1. Carsten

    Carsten Junior Member

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    A regular mechanic shop can do this?

    I've already drained the oil, it's mixed in with some other old oil, I could pull the pan and get whatever's left. Would that be enough?

    Not trying to sound snarky or anything, I've just never heard of this sort of thing being done before.
     
  2. vvillovv

    vvillovv Senior Member

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    Yeah, I'm still following and you're already in deeper than my comfort zone so I'll just be reading from this point on.
    hope ya get-her all patched up and no bent connectors.
     
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  3. BiomedO1

    BiomedO1 Senior Member

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    Sorry, according to those pics - All 4 cylinders had coolant invasion. The head gasket may have already been done to get the car running, so they could sell it with a know warped engine. Normally, coolant invasion only effects one maybe two cylinders - rarely seen all 4 leaking.
    The entire engine needs replacement, don't mess with any more testing. I'm guessing the previous owner overheated it many times and kept driving it. The reason nothing shows up on Carfax, it was a small independent shop that did the work, Not a chain repair shop that's linked into the insurance company repair database.

    Sorry again....
     
  4. vvillovv

    vvillovv Senior Member

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    There is another current Gen 3 head gasket thread that is similar to this one and has posted about getting an engine at JDM engines in Orlando FL.
    I'll put a link to that thread here when I find it
    I found another Gen 3 head gasket replacement video that has some different methods than the GM videos
    Usually GM show how to keep the cams in a static position when removing the head. This one relies on knowing how to set timing to specs as explained where I've started the video at timestamp 15:45



    I'd be luck to remember how to reassemble after getting the valve cover off, without putting bolts, nuts and harness connects back on without loosing um or puttin a long bolt in a shallow socket.
     
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  5. vvillovv

    vvillovv Senior Member

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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    Screen grab from the video posted in #64, definitely a different look to the new Toyota gasket (he notes it's Toyota). This jives with what The Car Care Nut said in a video, that it's revised:

    upload_2025-2-13_13-49-35.png
     
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  7. vvillovv

    vvillovv Senior Member

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    from video dialog "Boom Boom Boom" :cool:
    "I'm just gonna turn a 90 on each one" :censored: looked like 45 to me except the first one in normal time.
    I like the sound of that engine, thanks Nick, quick with as little drift as possible in the shop stall.

    Now if I could only find those nuts I lost and figure out where these extra ones are supposed to go. :coffee::whistle::whistle:
     
  8. douglasjre

    douglasjre Senior Member

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    When you buy aftermarket gaskets you miss out on all the collective wisdom from the warranty process and the engineering refinement with tsbs and superseded parts. Why would you buy junk from China where there's no accountability and no concern for the outcome? If you think Toyota made such a great car then how is it that suddenly you think Chinese parts are great for your Japanese car? You don't so admit it. You just being cheap and buying junk and hoping for a good outcome if you buy aftermarket. But it never plays out the way you hope. OEM my friends. No exceptions
     
  9. Carsten

    Carsten Junior Member

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    Well, it's all back together and running great! ... so far.

    There were of course a few hiccups but before that... I took the cylinder head to a machine shop, the guy's been doing it for 45 years. Explained the situation, he didn't seem to think it was unsalvageable. $550 later I have a cleaned up head that he says is like new.

    Friday morning I commenced reassembly, which also included the cleaning of mating surfaces etc. The 1st hiccup came when the $40 Beck Arnley 0161075 head bolts I ordered from rockauto apparently accept a different double hex socket than the OEM. I had also gotten the head bolt socket set from from rockauto W83184 this was a total score for $8 you get a M8 and a M10, Azone sells just the M10 for like $70. Anyway, the bolts were neither of these, M9 maybe? Thankfully, an Azone nearby had some in stock for $80.

    The video vvillovv posted in #64 was very useful in that the guy left the exhaust manifold on the head, disconnecting it from the exhaust pipe. It occured to me that this might be easier than monkeying around with the EGR etc the way Gasket Masters do, just leave it all on the head. So I took the exhaust manifold off and put in on the head along with the EGR etc and then mounted it on the block, it's heavier but I think this saves time and hassle.

    Late afternoon the 2nd hiccup came when I discovered that the Fel-Pro head gasket kit didn't actually have everything I needed, in fact there's no parts list telling you what's what. As I recall the missing parts were - one of the EGR gaskets, gasket for small coolant manifold thing near the EGR, some O rings on top of the camshaft bearing caps, O rings for oil filter housing, and coil to valve cover boots (maybe I shouldn't have expected these to be in there).

    Saturday morning I continued and was able to get O rings from the dealer, I reused the EGR gasket and siliconed the coolant manifold. Also discovered that the Fel-Pro valve cover gasket doesn't fit so I reused the old one.

    My ears are burning now after douglasjre's lecture above. I feel sort of like an addict, aftermarket parts are so tempting.. they're cheap and I'm a cheapskate. Have I learned my lesson, time will tell.

    In the afternoon I had it back together enough to fire it up. Did so and, hiccup 3, immediately gas was running out of the fuel rail at cylinder #1 like a drinking fountain! When I had taken everything apart weeks earlier I discovered one of the injectors was missing the little plastic cap on the tip (attached pic), I ordered one to replace it. Then one day, I had left the injectors in the rail, for some reason, fuel pressure forced on of the injectors out and it fell down into the sludge in my catch pan. I had pulled what I thought was the fuse for the fuel pump. Blah blah blah, I cleaned off the dirty injector, swapped it, and the leak stopped.

    Hiccup 4 - started it up again, misfire cylinder #3. Swapped coils and spark plugs, misfire #1. Replaced spark plug, since that is what I had moved to #1, still misfire. Went to swap injectors and discovered that the electrical connector wasn't on all the way, now I had sort of noticed that I didn't hear a click when I put it on but I thought I just missed it. Upon closer examination I discovered that the little orange rubber gasket inside the connector had gotten out of place, took a tiny flathead and pushed it back into place.

    Started it up and it purred, no codes! Drove it around the block, no codes. Drove it 10 miles at 40 - 70 mph, no codes and averaged 56.2 mpg!

    YES!!!
     

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  10. Carsten

    Carsten Junior Member

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    Thank you, this was really helpful. See my latest post.
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    I’ve heard similar comments about the Felpro “gasket kit”, word to the wise. Toyota part nos for gasket kit and head bolts in attached.

    Did you clean the EGR and intake manifold thoroughly?
     

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  12. Carsten

    Carsten Junior Member

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    Indeed
    I went with Fel Pro mainly because Gasket Masters recommended it, of course they were talking about just the head gasket not the whole kit. Now I know better.
     
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  13. BiomedO1

    BiomedO1 Senior Member

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    The trick is to put a bit of dielectric grease on those electronic connectors. They slip in easier and is another nice moisture barrier.
     
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