Gen 4 engine swap worth it?

Throwing in the towel on your current engine and putting in another, used engine, is a gamble. Neither JDM nor a salvage 4th gen are mechanic-vetted, and the latter has proven prone to overheat IIRC.

Why’s it leaking? Did the block/head interface get checked for flatness? Was the EGR system (including intake manifold EGR passages) cleaned? Any chance of a bent piston arm?

What symptoms are you seeing now?

bottom link in my signature is full engine section, has the flatness specs.

 

The damper between engine and transaxle might have been compromised too.

still, cold-start rattle: borescope time.

what’s DNJ, googles no help.

 

There’s a couple of Toyota kits, both with head gasket. The more complete one is best bet, not much more.

 

IMHO; unless you get a VIN with that engine - you can't verify.
A used gen4 will only get rid of the lower end oil burn issue. You can get rid of that with an updated rebuilt motor. That would certainly last more than 5K miles. Most people will move their old head over to avoid major modifications.
Did you change the electric water pump and add a P10 HUD to monitor your engine coolant temperature? Your temp. lamp doesn't go off until 248F+ and normal operating temp is 185F-210F. Chances are that there was a slight warp on your engine block, but if the engine was running hotter than normal - but below 248F, you'd never know...... That would pop your head gasket too....
Did you go back in after break-in to re-torque the head bolts?

 

Latest part no (and official Toyota name), for the full gasket kit,

Toyota Genuine Engine Overhaul Gasket Set 04111-37316

Also, attached is a pdf I made, of a summary done by a priuschat member @Carall, id'ing content of the head-end gasket kit.

Here's his post:

2013 Prius Two Head Gasket Set Part Number? | Page 2 | PriusChat

There's some back-and-forth, regarding the two kit, and p/n revisions. Bottom line, the bold line (above) is the latest p/n, for the full engine rebuild kit.

 

is there a thread here where someone has put in a gen 4 without issues?

 

@cnc97 was the first I think, and he ended up doing just the 4th gen block, kept his thrird gen head. And no problems IIRC.

Personally, if it EVER was block issues on ours, think I'd go for a new, 3rd gen short block.

 

check with hybrid pit in cali

 

Hyrbrid pit in california....

 

Sorry I haven't done a aluminum block in a long while, so I had to look it up. When i used to do this in high school and college; we always go back in after 500 miles and re-torque. Here's the reference I came up with.
Aluminum heads - retorque or no? - Don Terrill’s Speed-Talk
I've been out of the game too long to give you a definitive answer; Sorry..... but it wouldn't hurt since your screwed anyways. Just be genital and careful; your dealing with aluminum NOT iron. It won't help if your block is slightly warped.

 

They are stretch bolts. No need to retorque.....

Remember, you torque to certain amount, then 2 90 degree turns...
How would you retorque? There is no amount to retorque too.

 

Assuming new stretch bolts was used

You back-off one rotation, retorque and restretch - this isn't rocket science. If you mark each bolt before starting; You'll see if you may have missed one - the marks will be way off from the rest. They should land within a few mm of each other after the re torquing otherwise they must've been loose.

 

Doesn't matter. If they are within specs, you can reuse them.
I didn't, I bought new ones. They were inexpensive enough.