ZVW30 Engine Oil Analysis

I have no idea either Bob, but break-in oil usually has lots of copper and Si. That's what is being broken in, the bearings and the aluminum (aluminum is a matrix with silicone for strength), with iron from the rings/cylinder walls. No water is a good result! I didn't see any mention of gasoline content. Perhaps I missed it. That's another thing to watch for. It shows if "startup choke mode" is working properly.

Thanks for posting!

 

The silicon also could be coming from sand particles related to the original castings.

Does anyone know if the information on viscosity can help to identify the original grade of the oil from the factory?

 

I don't know if you saw this thread:

http://priuschat.com/forums/gen-iii...ooting/68094-uoa-oe-toyota-oil-998-miles.html

The Si and Moly ppms are comparable to yours although they used Blackstone.

 

If you have ever overhauled an engine, Moly is the thin black grease you smeared on the cam lobes and the bottom of the lifters, very good high pressure lube, you will also find it in CV joints, mechanic slang for it is Moly Be Damn. Hard to pronounce Molybdenum if you are a country boy.

 

Oil analysis is a tool. As with all tools, they have one or more specific purposes. Having or using them for purposes other than intended is usually a waste of the price of the tool. As a pilot and airplane owner, I have my oil tested every oil change. I plot the results on a graph.

The main point of oil analysis is to look at trends. Each engine component is made from different metals. Concentrations, or more accurately, changes in concentration of traces of these metals can show what parts are experiencing increasing wear and potential prone to failure in the future. Aircraft engines are routinely overhauled and sometimes have partial or "top" overhauls prior to a complete overhaul. Oil analysis can show when rings, bearings, valves or other engine parts are ready for an overhaul.

Pilots and aircraft owners do this as an engine failure or perhaps an decrease in power could have catastrophic results, e.g, you die. Even if a worst case event does not happen, a catastrophic engine failure usually results in a total engine loss (very expensive). It is difficult to hear the engine clearly in an airplane and minor noises are not often heard so small problems may not be diagnosed by other means.

Piston aircraft engines are routinely run at levels between 70% and 100% of their rated power. At high power levels, engines create and retain more heat. At temps over 400 dF and especially above 460 dF, the metals in the engines become softer and become more prone premature or excessive wear. Add to this that aircraft engines are air cooled, which is not nearly as efficient at regulating engine temperature as a water cooled engine and the concerns with engine heat are increased. These engines are not controlled by computers as auto engines are. Tthe pilot must manually adjust the fuel air mixture to compensate for the varying density of air as altitudes change. Minor mistakes in operation can lead to significant engine problems including detonation (preignition) and overly hot engine operating temps. Lastly, these engines operate in outside air temperature ranges from over 100 to well under -0- dF, often hitting both extremes in a matter of hours.

Cars on the other hand are water cooled with thermostats to help engines reach their ideal operating temperature range more quickly and once warm. Auto engines run at a very low percentage of their rated power most of the time. At lower power setting, they create a lot less heat. Overall, auto engine temps are relatively constant. (When is the last time anyone ever had a car overheat?) Auto engines also have timing and fuel air ratios controlled by computers thousand of times per second, keeping everything nearly perfect. Since most cars are only driven between sea level and maybe 8,000', air density does not change that much. Compared to aircraft engines, cars are downright pampered.

Lots of other users have their oil analyzed for many reasons, but I have never heard of anyone, other than someone selling the service, recommending it for normal passenger vehicles used typically. I'd suggest that it is a racket, just like using nitrogen to inflate tires.

The poster who suggested that you were breaking in the engine and not to worry was correct. The entire purpose of breaking-in an engine is to scrape off and eliminate a lot of these excess metals, get parts to fit better, etc.

If you have a lot of money to spend, go ahead and have your oil tested every oil change and plot the concentrations of various metals. When you see a trend of one or more allows spiking, you will know that you are having a problem. Bring that to a dealer and they will probably do nothing until their computer diagnoses a problem or you have a failure. Of course, if you post the results, you will educate the rest of us.

One more point if anyone is still awake and interested - One more comparison: Most piston aircraft engines are rated with a "TBO" (Time Between Overhaul) of 2,000 hours. Assuming that the aircraft has an average speed of 150 knots, which equals about 172 mph, this would be approximately 345,000 miles. Not bad for an engine so abused.

 

You know, Bob's first sentence was I'm not a great fan of engine oil analysis,
And JATiii, as an A&P/IA, I can tell you your probably wasting your money UOA for your aircraft too.
And hey welcome to PC:tea:

 

Thanks, it is an interesting forum. A64, I gotta ask, do you dislike full engine instrumentation and operating LOP too?

Since my last engine went 1,000 hours past TBO, I feel that I got my money's worth, if only for confidence - a good thing while flying over open water.

 

A little off topic here, but if the mods don't mind? Bob's a pile-it too, so I don't think he will.
I have three airplanes, two Cessna's and a Maule. The C-210 has an EI UBG-16, GAMI injectors and it's IO-520 Continental runs fine LOP. The Maule has a Lycoming IO-540, UBG-16, and GAMI's and will run smooth LOP, but power drops off so badly and when you compute mileage (both have digital fuel flows from the UBG-16) the mileage is the same ROP and LOP. The Conti on the other hand will shows an almost 20% improvement in fuel mileage / range, but you lose 10+ kt cruise. Soon the Maule will have EI's MVP-50P, but that will require a whole new instrument panel.
To operate LOP safely, you must be fuel injected and have the ability to monitor each cylinder individually.
MVP-50P Overview

So no, I'm not against LOP, but it just doesn't seem to work in all engines

 

I don't think the aluminum is coming from "lapping" the cylinder walls. They are steel inserts. It's -possible- to use aluminum cylinder walls (Chev. did it on the Vega and several motorcycles and lawnmower engines also did). But if you even -think- about overheating the engine, even slightly, the engine will be toast. Which is what happened to most of the Vega engines. I think this episode taught the industry a lesson. I haven't seen an aluminum cylinder wall in years. I -have- seen plated aluminum. Chrome plating is often used in racing engines and rotaries and other more exotic sputtering plated walls are also used. The advantage is better heat removal. The disadvantage is if -anything- goes even slightly wrong, the plating is destroyed and the casting (block) is toast.

It's funny if it doesn't happen to you, but with, for example, the Mazda rotary, third gen engine, if you run too lean the fuel will detonate. The shock waves generated will crack the apex seals. The bits of seal will destroy the chrome plating (new rotor housing please), and then exit the engine and take out the $8000 turbos. Nice eh?

I suspect the aluminum is coming off the cast block and other parts. Micro particles as the oil "cleans" the engine interior.
Yes, most of the silicone is coming from the sand casting "leftovers". They do clean it well, but there is always -some- that gets trapped in the aluminum, and releases when that is cleaned off/broken off by vibration and temp. cycling.

 

Sorry to stay off-topic. I agree 100 pct. Usually the fuel savings and better engine life far outweigh the minor loss of speed, but you can usually increase power settings to get back the lost speed and still save fuel. Blue skies.

 

I found a couple of oil analyses on the following thread and just wanted to link them to this thread because I had trouble finding them:

http://priuschat.com/forums/gen-iii...ng/68805-gen-iii-oil-change-1400-miles-4.html

 

Here my report @5103 miles