Bottom EGR Cooler Nut Accessible From Bottom?

You can do it from below.

I did it that way the first time I did our old 2010’s cooler.

Good luck with the cleaning and assembly process and keep us posted .

 

For removal, I reached that nut from above, played around with various ratchet wrenches, sockets (normal and deep) and various extension lengths. You need just the right length of extensions to be able to fish through the mishmash of cables and hoses to the right of the EGR (as you stand at the front of engine). 3" and 6" extensions are good to have on hand, and 1.5", for fine tuning. I believe I needed the 1.5", and maybe a 3" as well. Stubby and deep socket help to finetune the reach further.

I was using a sweet long-handled Jet wrench with a swivel head, which helped too. The swivel head makes it easier to snake it in straight, then unswivel, bring the handle back closer to 90 deg, once you've got the socket on the nut.

Going in with extensions, I believe that nut is just beyond and a little low, offset from a largish coolant hose going into the head. Say around 4:30, if the coolant hose was a clock face.

FWIW, you can touch the nut, if you reach all the way around the EGR cooler from the left side, clockwise reaching around. Doesn't help much when you're trying to break it loose, but does when reinstalling, or to catch it during removal.

I believe @Raytheeagle doesn't reinstall that nut after. The more I think about that, the brighter it sounds.

 

One option I’ve been doing on that lower back but is simply use the E8 torx socket and rotate that out.

Why mess with the nut if you don’t have too since you’re removing the stud anyway.

And I do not reinstall the lower cooler support nut which fastens the cooler to the engine block (that’s off topic for the OP’s question, but since @Mendel Leisk brought it up thought I’d share). There is a stud there for alignment and there are at least 5 other ways to support and stabilize the cooler into place.

One less nuisance the next time.

 

The night before I got into the EGR removal, I started by working on that one nut, wanted to make sure I could reach it and get a purchase on it, break it loose.

Further, regarding the need for that nut: @Ragingfit installed a 3rd gen EGR system on a 4th gen engine, a couple of times now (in a 3rd gen Prius and Prius v): none of the intermediate bolt locations work, so it free-spans from the exhaust to intake manifold connections.

 

Mine was nowhere near that bad. Chalk it to 150K miles and nasty winter localle?

Just to verify: you're aware the bottom stud, the one with the nut removal we were discussing before, does not need to come off, to get the cooler off?

Standing a the driver's side fender, you just pull the cooler towards you. That's how @NutzAboutBolts manages, in his video.

About 11 minutes in he's getting close:

At 12:40 he mentions no need to remove the bottom stud.

 

The job isn’t tough but you are starting to see how fiddly it can be.

I’ve tested my skills to the point where I did the egr cooler swap WITHOUT removing the windshield wiper cowling .

Wouldn’t recommend that method though as it is time consuming .

Where there is a will, there’s a way. Keep your head up and you’ll get there.

I wouldn’t suspect welding of components, just be difficult .

 

I’d say remove the lower stud from under the cooler to engine block connection and you’ll have only one point of resistance .

That is also an E8 torx socket stud, so you have the tools you need.

Another option to get you through.

 

Maybe just a stupid question: you've got these two nuts and studs removed?

 

The more of these EGR threads I read, the more I’m glad I got a “Florida” Prius.

 

Think of the studs present there as a triangle.

If you remove 2 of the 3 sides, you’ll have what you need to proceed and remove binding.

 

Yeah back studs, connecting to exhaust comes out. And IIRC the front stud, at the underside of the valve, also comes out (could check the video to confirm)*. But sure as shooting the bottom stud can be left as-is.

* yeah, that stud comes out, around 11:50 of @NutzAboutBolts video above.

 

A cool head often prevails when faced with an issue.

Breaking a stud can be stressful, but isn’t the end of the world.

I’d leave the snapped piece as is for now a figure out a way to get the job done and deal with the stud when not in a compromising position .

Better to work in an ergo friendly way when problem solving .

 

Ok, understand now, I think. The broken stud is the lower one, at connection to exhaust manifold. Also, by removing the stud on the "hidden" connection, the troublesome one on that extended bracket on underside of cooler, then you're able to fish the cooler out, broken stud and all?

You can track down the stud part no on this page:


EXHAUST GAS RECIRCULATION SYSTEM. 2013 Toyota Prius Two HYBRID | Toyota



This specifically, which looks to be a revised part:


2013 Toyota Prius Two HYBRID Bolt. Interchangeable with 90126a0019 - 9012608052 - Genuine Toyota Part