Its time for a rebuild.

I have had it since late 2017, bought it with 148k miles on the odometer. Its been mostly driven on highways.

Car has made at least 50 trips to Toronto (1300ish miles round trip) over the past few years, gets driven around 100 miles a day. I am religious when it comes to getting a timely oil change i.e. every 4000 miles, always had penzoil full synthetic oil. It had been burning a quart every 1200 or so miles for the past few years. It didnt have an oil catch can till recently after I installed the rebuilt motor.


Confucius says I have a lot cleaning up to do in the next couple of weeks.

I havent gotten to the cylinders yet, the cam looks good without any scoring so thats a relief, if the crankshaft, bores and head looks good I'll be rebuilding this one.

One thing I'd like to point is that the oil in the motor was only a month old at most, coolant was leaking into the combustion chamber and contaminating the oil as well. Lets see how bad this head gasket was blown.

 

Well it’s apart now; bearings look good but will be replaced anyway, scoring is present in the bore, I’ll see if honing takes care of it otherwise I might end up using the first block I opened with the rust putting and pair it with the good head that this block has, pistons look remarkably clean for the age and mileage and the oil control rings are not clogged with carbon.

I think the sludge build up is from the gasket been blown for a while and me driving the car for as long as I did before fixing it.

 

Well honing didn’t rid the scoring, I plan on talking to the machinist on Monday and dropping off the head and block with him, if it can be skimmed and kept within acceptable range then I’ll use this block, too bad Toyota doesn’t sell upsized pistons and rings, there are aftermarket options such as from DNJ but they are unavailable currently.

 

I am baffled as to how this motor got screwed this bad, the 140k or so I have put on this car has been mostly on the highway. The intake ports in the head are caked with carbon and I am thinking that over time has scored the inside of the bores.

One thing that I'd like to mention, when I cleaned the EGR cooler a couple of years ago I had to use welding wire to free up the inside passages of the EGR cooler, acetone alone just didnt cut it back then, the inside of the EGR cooler has small fins inside the passages may be to increase the surface area may be to block large carbon clumps to make their way into the intake. Those fins might have gotten damaged with the welding wire letting large particles in over time, thats the only explanation I can come up with. The hard driving on the highways alone cant do this sort of damage.

I am bringing the block and the head to the machine shop, hopefully today, head is going to get cleaned, skimmed and rebuilt (just paying them for the rebuilt/lapped valves etc as last time it took me a day or so to do all of that myself). Block is going there as well, I am going to bring both blocks to him, this one and the 140k miles one to see which one can be used with best results.

I have found DNJ pistons back in stock, they offer 0.5mm upsize rings and pistons, we'll see what Rick at RJT says, ideally I'd like to stick to the OEM revised pistons/rings. These are the current measurements of the above shown block after yesterday's honing session.

Cylinder # , Measurement at 10mm from top

1, 80.46
2, 80.46
3, 80.50
4, 80.48

Standard measurement is suggested to be 80.50 to 80.513mm

Maximum diameter measurement cant me more than 80.63mm

Cylinder 3 and 4 are the two with the most scoring and those are the two I aggressively honed.

 

Thank you, hence is why I am bringing everything to the machinist to pick his brain on what would be the best course of action at this point. If he says neither of the blocks are usable then the dead engine with the blown head gasket in my brother's car is coming out to see if that can be used.

I am glad that I picked up the $200 motor locally that I rebuilt and put in my car as if I had waited to use this block from my prius I would have been screwed, lol.

 

I think its $1800 or so, true?

I can bring it to his attention and see if he wants to go that route, knowing him probably not as he is already indicating we should pull out the dead motor and hedge our bets on that one or find a used 4th gen motor and transplant that in his car as I have done that before as well.

 

Well as luck would have it this thing popped up 10 minutes from where I am, it was worth a trip to go check it out. Owner bought a blown motor for the head only, paid him the $50 and brought it in, seems like the head gasket had been replaced once before due to the black rtv remains on the side cover, OE Rtv is gray.

All the bores are clean with no scoring and cross hatching still present albeit not as prominent as from factory but it will be fine once I hone it.

 

Just got the first oil change, everything looked good after 600 miles, cut open the oil filter to inspect for anything out of the ordinary and everything looked good. Here is what the catch can caught; coffee anyone ?

 

If you are keeping scores at home so far this thread had 3.5 different Prius engines in it .

Knowing myself I might end up rebuilding the one coming out of the dead Prius. May be I’ll start a core exchange program, buy the rebuilt one and send in your dead one