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Any tips or hints about removing the hidden EGR Cooler nut?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by R_W, Sep 9, 2020.

  1. R_W

    R_W Junior Member

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    I can see the hidden, underneath nut on the EGR Cooler in an installation video, so I've been able to find it with my fingers, but have had a difficult time trying to guide my socket on an extension over it. I looks like maybe if I remove a cloth-covered (heater?) hose underneath, I may be able to get to it, but I don't really know what's in that pipe and don't want to take it off if it's anything other than coolant (which I've drained for this repair).

    As I'm sitting here bleeding from my last attempt, does anyone have any hints or tips? Finding the right route for my socket, guiding it into place and having enough room to work has me (temporarily) at a loss. Everything else I have done or can see how to do. I'm just having trouble getting onto this nut.

    Any hints, tips, instructions,how-to links would be appreciated.

    Thanks!
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    I recently took off both the nut and the stud. Nothing else was off, say the windshield cowl for example. I believe I did remove the bolts on some of the conduit brackets in the vicinity, tried to pull things out of the way some.

    I was using a long-handled ratchet with a swivel-head, easier to snake it in there. I have extensions 1.5" and 3", regular and deep sockets. Played around with both trying to find a sweet spot for length.

    I found too, I had very limitted travel for ratchetting the wrench, was doing one or two clicks at best. Especially when extracting the stud (with a Torx socket). Took a punishing amount of time, and I was fearful it was going to seize.

    Bottom line, it's doable but barely.
     
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  3. The Critic

    The Critic Resident Critic

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    3” wobble extension and a deep 12mm socket.

    (3/8” drive of course.)
     
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  4. R_W

    R_W Junior Member

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    I have been trying with a long-handled flex head ratchet as @Mendel Leisk suggested and a 3" regular extension behind a deep socket, but it's almost like this could be too long because there is the hose and orange wires in the way. It almost looks like you have to weave between the hose and the wires and bend the socket around. Would a wobble extension on a flex head ratchet make a tremendous difference? I don't own one and wouldn't be opposed to the concept, but it would take some effort and maybe even another day to get one in my hand.

    On another subject, as a bit of additional info, in addition to having trouble weaving my way through the hose and cords, I want to stick both hands in there, one with the ratchet and one to guide, but I'm finding it difficult to do.

    ETA: I see a couple of people commented in reply to @NutzAboutBolts' video that it could be reached from underneath. I haven't tried having my son stand at the top and point toward the location because it's still during the virtual school day and he's in a streaming algebra class, but without that guidance, I'm not obviously seeing the path from underneath.

    BTW: In case anyone is looking for a clear pic of a clean cooler, I could see (what I assume to be) the bracket here.

    Thanks for any and all tips and ideas!
     
    #4 R_W, Sep 9, 2020
    Last edited: Sep 9, 2020
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    You can touch it if you sorta lie on the engine and reach your left hand around, going clockwise around the back. Still, that doesn't equate to a wrench on it, has to be from the right side.
     
  6. mjoo

    mjoo Senior Member

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    I reached it from underneath the vehicle. I was also able to feel it. It took me about 3-5 minutes with an open-ended wrench and lots of patience.
     
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  7. R_W

    R_W Junior Member

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    After seeing your reply, I went out to the car with my son and had him put his finger on the pipestem sticking off to the side near the nut, while I slid underneath with a halogen light. Looking up, I couldn't see his hand and looking down, he said he couldn't see a path to the light. The little Priuschat sidebar makes it appear we're working on the same model car, a 2010 Prius III. Of course I'm going to keep at it and if necessary, tomorrow I might need to go to the tool store to get either a wobble-head extension or a universal joint adapter or maybe even both. I know lots of people get it and maybe if I held my tongue right, but I still haven't found the trick.

    Thanks for the suggestion, but there's an aluminum plate-thing or the shiny bottom of a component in the way.

    Otherwise this evening, I guess I'll take off the intake manifold for cleaning because it's there and the video makes it look easy enough to do. I mean, after all, what's one more pile of parts taken off of my wife's car?

    Thanks!
     
    #7 R_W, Sep 9, 2020
    Last edited: Sep 9, 2020
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  8. Mendel Leisk

    Mendel Leisk Senior Member

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    As I recall, it's around 3 o'clock relative to the largish coolant hose (with black-braided sleeve). Not that you can see it, but if you start a socket headed in just around there your chances are good.
     
  9. Bradley P

    Bradley P New Member

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    I just did my egr/cooler/intake manifold cleaning this past weekend. For the bottom nut I used a deep socket with a 1” extension. I found it easier to get the socket on the nut first and then try to put the ratchet on the extension as the braided hose is quite close and you have to force it out of the way.

    If y don’t have a 1” extension you could use a 3/8 to 1/4 adapter on a 1/4 to 3/8 adapter to make your own version.

    Good luck
     
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  10. 2012 Prius v wagon 3

    2012 Prius v wagon 3 Active Member

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    Here are selected notes from when I did it earlier this year:

    I did a quick coolant drain to reduce concern for coolant hose removal.

    One difference vs. N+B video is I did not remove studs from rear end of EGR cooler. Instead I removed the front and middle side studs since I figured those were easier. Good decision.

    (and this is the nut you are wrestling with now: )
    Toughest nut + stud was the one on the side, middle fore-aft, low, through the bracket built into the EGR cooler. Taking the time to remove a couple of nearby hoses to improve access was mandatory. Also some work figuring out exactly the right combo of socket + extensions was key. I used: 12mm 1/4" drive deep Craftsman socket, with 3" extension, driven by 1/4" craftsman ratchet drive. Then E8 with similar (same?) extension and drive to remove the stud. Not so hard once I had figured all that out, so reinstalling was pretty easy.

    (^^^ when I say there that removing those hoses was "mandatory," those were notes to myself. Nothing is really mandatory. What I meant was that I struggled for a while, and then removed those hoses to let me get a better shot, and it was easy after that. BTW, the whole reason I take notes like this, on something I think I'll do again some day, is to save the time it took to learn all the little tricks.)

    ----
    Gloves really are mandatory too here. So easy to cut yourself, and necessary to fit your hands in there. I used cloth mechanics gloves, vs. the thin nitrile ones.

    On the selection of socket and extensions, I did not need any wobble, but it kind of had to be just the right length so I could fit the ratchet on it, etc. Not too long, not too short. Also thinner let it fit better, so the 1/4" drive. And deep well so it fits over the Torx stud without having to worry. Depending on what exact tools you have at your disposal, you may find a different optimal setup.
     
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  11. R_W

    R_W Junior Member

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    Okay, both @2012 Prius v wagon 3 and @Mendel Leisk said they also removed the stud. NAB's video said removing the stud wasn't necessary for this task, so I'm a bit confused and concerned enough that I might just put everything else on the cooler back because I have been counting on that stud to help guide the part back into place.

    As for the braided hose... it sounds like the a lot of people leave it in place, but trying to guide the socket onto the nut, the braided hose being so close and turning to some extent right in front of the nut makes it really in the way. What's in that hose? Is there a reason I shouldn't take it off? It looks easy enough to unfasten from side and to pull up out of the way, but I don't want to do it if some liquid will gush out from one side or the other -- the coolant was drained when I started the job.

    @Bradley P: Good idea about using an adapter and starting the socket first. Trying it is what showed me that the braided (heater?) hose is even more in the way than I had realized.

    Thanks!
     
  12. Paul E. Highway

    Paul E. Highway Active Member

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    I did a lot of the EGR cooler job lying across the top of the engine, starting at the right fender. I'm 6'3" 280 lbs and it was the best way for me to get my big hands in there. That nut was a matter of right socket/extension length so play around with those. When I finished up, I thought I would put the nut back on just for spite but I could not get it started and gave up! Minor blood loss from all the sharp bits.

    PEH
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    You can leave or remove (permanently) that lower stud I think. I don't think it's absence creates an alignment issue. If it's gone maybe you don't need to remove the the two rear studs?

    That braided hose is surely coolant. I don't think pulling it off would really help much, and unless you're completely draining the engine coolant (I drained only 2 qts, which was sufficient to leave the EGR components dry), you would be spilling quite a bit of coolant. With little advantage?
     
  14. The Critic

    The Critic Resident Critic

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    For me it does. I just recall squeezing the socket and extension combo in there. Get the wobble extension set from HF.
     
  15. R_W

    R_W Junior Member

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    @The Critic: My local Harbor Freight has very short pandemic hours, so it'd be tomorrow afternoon before I can get there. I see Home Depot has a set that sounds kind of similar, but it's more than twice the price as HF and while I could get that tonight, the description isn't exactly the same and I'd rather save the ten bucks.

    @Mendel Leisk: I completely drained the engine coolant. It's an acceptable time to change it and I felt it was easier than clamping off all the hoses. So, if the car is completely drained of engine coolant, there is no risk to disconnecting the hose? It feels like it's sort of partially in front of the nut. I could try loosening it and wiggling it around, but I'm thinking it might be better out of the way.

    @Paul E. Highway: You aren't the first person I've seen say they didn't put the nut back on when all is said and done. If it's not going to make an excessive rattle or hurt anything, sounds like a good idea to me.
     
    #15 R_W, Sep 9, 2020
    Last edited: Sep 9, 2020
  16. The Critic

    The Critic Resident Critic

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    Wobble Socket Extension Set, 9 Pc.

    That’s fair. I think I have this set.
     
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  17. Mendel Leisk

    Mendel Leisk Senior Member

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    Just for next time: if you drain just 2 qts, the EGR will be dry. You can pour it back into reservoir after.

    Clamping hoses is not that effective: the bulk of the coolant that'll spill is in the cooler, above at least one of the hoses, so the coolant just runs out regardless.

    For throttle body removal, the coolant lines can be left connected; they have plenty of slack.
     
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  18. 2012 Prius v wagon 3

    2012 Prius v wagon 3 Active Member

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    You can either remove both of the rear studs as N+B do, or you can leave them in place and remove the two side studs, as I did. Seemed like it would be easier the way I did it, and it was, for me.

    If you remove the rear studs, you don't need to remove this middle one. Check.

    If you don't remove the rear studs, the cooler will not come off unless you remove this middle one.
     
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  19. R_W

    R_W Junior Member

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    @2012 Prius v wagon 3: I just went step by step through the video, one or two minutes at a time, watching at least one of the ads per break so he would get paid, until I got to the lower, hidden nut. Then, after I got stuck, I skipped over it and did the rest. So, I've already done the rear studs. Maybe because I'm tall, they weren't difficult for me. Though, I am going to try the guy's trick in the video with a corner of masking tape to hold the gasket in place because that looks like a good trick.
     
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  20. Steven Stolle

    Steven Stolle Junior Member

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    I had a difficult time with that nut too. I used a 3/8" ratchet with a wobble extension and deep socket. I wrapped electricians tape around the extension & socket to make it flexible. I didn't want to lose it to the void if it came apart. I worked it in to place carefully until the docket engaged the nut. It came loose easily. Just be careful not to drop the nut into the void. Good luck!

    Posted via the PriusChat mobile app.
     
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