Do you think this happens is because of heat or because piston hits the spark plug by inertia after being let free of the rod? It is even possible?

 

I thought about that scenario in my mind where the piston hits the plug, but in the cases my uncle and I had to deal with, there was no damage from a hit, my uncle clearly saw heat was at play, plus in your case you had two cylinders having such damage, and only one with a bad rod.

 

I agree. But this makes me think of my injectors. They are funking plastic. If ceramics cracked because of heat I am really scared to think of condition of plastics. They are really expensive.

 

Ough, wait. I am sorry. They go into lower manifold, not to the heads. But anyway, do you think that there was enough heat transfered in order to damage them? I hope not, because heads where cooling pretty good. But plugs? They are in the lower part of heads. Man, I am really confused. Nothing makes any sense. Where is that coolant temperature sensor? Is it near thermostat or lower?

 

I'm thinking it was just the forces of #5 turning loose that caused the other plug to crack. There's a lot of damage to your block from that one event, I'm not surprised that something like a ceramic plug cracked. I've seen more than my share of engines that have blown and rarely is the damage limited to just that one cylinder that turned loose.

 

I couldn't remember if you had pieces of the piston, or was it just the rod, as pieces of piston can fly up and cause issues (not the whole piston).

Anyways, I know that hot running RX7 rotary engines have suffered cracked plugs from heat (I have a buddy listed on page 2 of my car domain page, who knows about this). It can happen.

Now with that coolant sensor, I remember looking this up and I think if I have this right, there is a sensor located in this region, and it has a connector that comes in vertically.

 

That's so true on your comments of the damage not being limited

 

Okay, got my RX back with new engine. About to test drive it on a highway. Driving from Irving to Plano using Bush turnpike, and back thru Frisco using TX-121. Anybody sees me - wave, or something ;-)
Mechanics told me of break in period of 1000 miles. So I am driving it really nice for the next 2 weeks.
Will post pictures of new engine and what they did to my RX.
It is running on gold German Castrol 0w30 now. Took 7 quarts to completely fill the dry engine. I also added 2.5 onces of everybody favorite RxP in the full gas tank. Will be doing to every other tank.

 

Good to hear, Autozone has GC on sale for $4.49 a quart.
http://www.autozone.com/images/in_ou...g4_0531_07.pdf
My current GC fill has 3200 miles, I will send a sample for an oil analysis report @ 7K miles and post the result for those who are interested.

 

Congrats on the completed project! It should last a long time with proper care, but we both thought that of the original engine didn't we? The wife and I are seriously considering an '03 GX so our RX may be history, time wil tell, not to mention financing.

 

Good luck to you as well, Toyota V8 is one of the most reliable and durable engines of the world. Be sure to use 0w-20 oil for better startup flow, esp for Alaska winter!

 

So will I at 5K with new engine. Which lab are you using?

 

Don't forget if the last part goes thru... You know from PMs.

 

Too tired right now, I will post pictures tomorrow.
Anyway, I made 102 miles today (total engine mileage ~110 miles).
First I reset the MPG. Drove about 45 miles there with an average of 10.1 MPG (70% highway), did throw P0171 and related codes.
Parked for 3 hours, went to pool, had a 12-pack with friends. Cleared codes. Reset MPG. Went back home with average 17.8 MPG (almost same road).
Going to bed now.

 

Oil Analyzer, which for $20 will include TBN, oxidation %, and nitration %. Blackstone is not bad, includes insoluble % but charges $10 more for TBN.
Whoever get to the first report back can start a new thread.
Actually it is very good to get an UOA for the new engine, that is a good baseline for future reference.