head gasket and bent piston #1 connecting rod

What started as a head gasket replacement on my 2012 Prius and replacement of all the associated wear items, turned into a connecting rod replacement. Once I removed the head, I checked the piston height on suspect #3 and it was slightly lower that #2. After reading comments that I’d have to pull the engine, I took a shot at dropping the large pan instead while the engine was left in place. I got rid of my engine hoist and load balancer years ago thinking I was done with these kinds of projects.

I already had the timing chain cover off, so I removed the small chain that drives the oil pump, disconnected the air compressor, removed the starter block-off plate and removed all the bolts securing the oil pan to the block. From the front of the engine (looking at the timing gear), I started a wedge between the halves using gentle persuasion (aka hammer) and split the halves. With a little wiggling, the large pan dropped right out pretty easily.

Now I have access to the full length of the crank. Within 10 minutes, I had the #3 connecting rod and piston driven out through the top of the block. My plan is now to buy a new rod, re-ring all the pistons, hone the cylinders, install new rod bearings and begin assembly.

 

Replace the old piston rings? They may be discontinued, not sure. They are low-tension, have proven prone to oil burning, after maybe 150k miles. That said, if the old rings are available, it’ll likely be trouble free for the practical lifetime of the car.

Toyota revised the pistons, belatedly, partway through model year 2014. If you get the new rings, you will have to replace pistons too (groove size is different). And I’m guessing you should do all four? Attached has info on revised piston/ring part numbers, and dealership would know the latest.

you’re the second to report here about dropping the upper oil pan for access, good to know.

Did you see any recess at the upper oil pan to block interface, purpose-built for tapping a wedge. There is one at the underside between engine and transaxle; @Ragingfit notes In his engine transplant video series:

Swapping in a Gen 4 Prius' 2ZR Engine into the Prius v | PriusChat

I’ve never done anything remotely close, probably never will need to, at the snail’s pace we’re putting kms on our ‘10, but I like to follow along.

 

Curious if wiggling is needed to install it. Which could mess up the sealer....
If possible, video it.

?With a little wiggling, the large pan dropped right out pretty easily.

 

BTW, if you don’t have it, last link in my signature is full engine section, albeit with dead links. (On a phone turn it landscape to see signatures).

 

Good video on engine overhaul, including piston/ring replacement here:

Decent Replace 1.8L Pistons and Rings Video - Engine Out | PriusChat

“part 2” video in particular.