I get my gas from am much older station outside the city of Dallas, because the fuel is ethanol free.

I actually have a couple of shop vacuum gauges. I have two that are carb mounted for synchronizing the dual carbs on my 1958 porsche, and I have a diagnostic one. I am more looking for one to install in the car permanently.

All modern fuel tankers have a full flow 4 inch quick coupling with a sight glass, and the vent in the tank to allow the gravity flow is either in the back of the station, or in the non attainment pollution cities like Austin, Dallas, Houston, and San Antonio vented back into the tanker with stage II vapor recovery.

Now that's for keeping the fuel and vapors in the system, not necessarily worrying about dirt or water.

I hauled fuel from a small bobtail 2000 gal. truck from 16 to 54 years old, and I never ruined a batch of fuel or heard of it by getting dirt in it.

I've checked the tank levels with a stick thousands of times, and sometimes you can feel the sediment of rust or dirt in the bottom, but it always stays there if the suction tube is installed at 5 inches above the bottom like it should be.

When the station pumps your fuel, the filter in their pump will slow down to nothing if any dirt was to get sucked up.

If you found unfiltered fuel (highly unlikely), then, your car fuel filter and or pump will plug up, your car will surge a lot, and quit until fixed.

There is absolutely no way to squirt dirt through the injectors.

Engine oil gets dirt inside only one way; through the air filter or intake leak.

10 ppm dirt in 1year of running in West Texas is almost nothing, and virgin analysis of this oil has shown around 4ppm from Mobil as an anti-foam agent.

It's amazing that such a tiny engine puts out so much power.

Back to the topic, has it been mentioned on here that if you're using magnets on your oil pan and/or oil filter, your UOA may say that you have minimal wear when you in fact do not?

So how many here with UOAs showing low viscosity, are running in the 9-9.5k range during their daily carbon burns? I used to, but when I realized how much more heat is generated in that RPM range, I've slowed my roll for daily carbon burns to 7.5-8k. I still run it to 9-9.5k on occasion, but not every day.

OD, I'm surprised to see that your 15w40 Rotella is showing up with low viscosity after only 2k miles!

If the fuel dilution is the culprit, is there any additive which can safely be added to the oil on a rotary, which would help to neutralize the gas some? Is it only a dilution issue, or is 2% gas in your oil going to breakdown the viscosity of the oil faster than 2% water in your oil would?

It has not been mentioned because it's bunk.

...Unless somebody has invented a magnet that grabs copper, chromium, aluminum, and lead and is about to become a gazillionaire as a result. Those are the wear metals you have to get through before you get to the iron. And the filter itself is going to catch any significant iron anyway. If you doubt me, email Blackstone and ask them directly, then post their response here.

I guess my UOAs show low viscosity, and I track mine and rev the snot out of it. But just try and stop me from running to 9000 RPM every day. I have to, it's on my license plate:
https://www.rx8club.com/image.php?u=...3&type=profile :evil_laug

lol, well on that note, a filter only collects something like 20% of the oil that passes through it.

/\ in Series 1 yes, Series II's ALL Engine Oil goes through Oil Filter First, unless your oil filter (S2) is blocked and in by pass mode.

My Filtermag catches HEAPS of ultra fine metal below 25 micron, which an Oil Filter can not catch.
It is like a Black Toothpaste...similar to Transmission and Diff magnet drain plugs in ALL Mazda's.

BUNK it is not...I guess you would rather have this floating around in Engine...

And I guess you can tell me why Mazda for the first time put an internal sump magnet in the Series II's?, since 1985?, because it is Bunk, I guess.

Better than Nothing..

I know you can get a bypass oil filter, or you can add a spin on bypass filter/dual filter system to the car if your that worried about it and catch something like 99% of all particles.

Read more carefully: It is BUNK that a magnet will mean a UOA will show less wear. Unless your magnet catches lead, chromium, copper, and aluminum. In which case you should patent it as you are about to become a bazillionaire.

If you don't believe me, ask Blackstone directly and post their response here.

Huh?

2% gas immediately dilutes the viscosity.

That's another reason 5w20 is too thin for the 8.

The viscosity of water is not too far off for a bearing, but ANY water in the oil especially with antifreeze is a bearing killer, and shows that the water jacket seals are leaking; Big problem!

Water has good cohesion, but is a polar molecule that repels so it won't stick to what it's supposed to lube, and doesn't feel slick.

Good stuff. Fuel dilution was the reason I decided I want to get my injectors flow tested and cleaned. But, we will see when my next UOA comes back if I bother to do that or not. I have 120,000 on my injectors so i think it is time but some other stuff I have read indicates that as long as they are clean, they can last forever.

I can say though that I replaced my OMP lines and oil injectors and my oil injectors were clogged and fouled up. I will post up pics soon.

Oil sample is being sent off in the morning, I even splurged for the TBN :P it says 4 weeks, lets hope not.

So it took 16 days to get the lab results back, and they don't look good. Lesson here for others? Don't race your RX8 lol. Although it does say these results are normal for a vehicle that is raced.

Chromium 5X the normal amount :(
Iron 2X the normal amount :(
Lead 6X the normal amount :(

The oil however did hold up. Some of the numbers are pretty impressive for the heat, and abuse the vehicle withstood in the Texas summer. I am curious though since the car is tracked should I change the oil more, or Since the oil itself showed great results should I wait longer to change it. I am going to go with a time frame this time. This was a 6 month oil change. Since this car is not a daily driver the miles added up a lot slower. I am going to do a 3 or 4 month change and see what the difference is. The engine does have 81K on it at this point, oil filter is K&N performance gold, coils plugs and wires are at 65K, Transmission and Diff have less than 4 month old Redline Oil on them. I will get those oils checked on the yearly clean ups. The diff I take apart and clean before refilling, the transmission gets a drain and fill.

Attachment 249303

It actually says for a race engine. Just because you tracked a bit bit doesn't mean much, Most of the other UOA's posted have track days in Texas on them. Castrol has typically tested well and I ran 10W30 GTX in my second motor for 75,000 miles and it tested fairly well but you may want to look into a good synthetic and the SOHN adapter. 0W-40 all the way. But the damage may be done already though so you may want to get a compression test just to make sure. IF you have good compression then start premixing and run the SOHN so you can add some good synthetic oil in the motor.

Thanks for posting up.

Blackstone still doesn't know WTF they are talking about when it comes to rotaries. How the F is the chrome from the apex seals going to get into the oil? :dunno: It can't, obviously.

Nonetheless, Doc, those numbers are very bad. You've hurt your motor. Running 5W-30 is clearly a mistake. Minimum viscosity for the track is 10W-30. I track the snot out of my car and run Rotella-T 15W-40 now and don't see the drop in viscosity you see on your report. Nor do I see anywhere near the wear. But I've never run the 5W-30 or the utterly inadequate factory-recommend (PTOOOIE!) 5W-20.

Yep, and look at REDRX3RX8's UOA with Mobil1 0W-40, he had few track (not autox) weekends on his UOA. I switched back to Mobil1 0W-40 recently but ran 5W-40 Rotella T6 with good results.

Doc, I don't know how your oil got that thin with only a trace of fuel, but you need to thicken it up to at least 10 cst.

I've never seen 5w20 that thin even, and yes, there's those internal gears that have chrome.

I notice that Mobil 1 0w40 specs have changed slightly to 3.8 HTHS viscosity instead of 3.7.

Minimum HTHS viscosity for minimum wear is considered 3.5.

What you're running might be a close to a 2.0 HTHS viscosity.

Considering that its the seals that give way before the crank or bearings, you probably haven't ruined it, yet.

I still like Mobil 1 0w40; many expensive cars are factory filled with it now.

I had a compression test done a couple of months back. The vehicle passed. I was there and saw the results myself. I was hoping to get a new engine lol, but we see how that worked out. I will switch to 10W40 and see where it goes. I am considering running the factory recommended since this engine is closing in on 100,000K. The miles on the car were 80700 when I sent that in. Its the original engine. I originally believed that they replaced th engine after talking to a rep on the phone. Then when I actually went and looked at the report it wasnt the engine that was replaced. It was just the plugs, wires, coils, battery, and starter were all done at the same time. Found that out when I had a compression test done. Vehicle passed the compression test. I am going back in 6 months around June to get another test done. My vehicle starts right up hot or cold. Never misfires, never stutters. Its seen wide open throttle for time on end. I redline it all day long.

Good to hear!

Back in the 70's 10w40 was the best gasoline engine oil, but we had a mechanic ranting about how he had a Ford Escort that was ruined from hard carbon (it was probably misfiring and leftover half burned gas was doing it since we didn't have any other complaints).

The lastest oil formulations for gasoline are 0w20, 0w30, 0w40, and 5w40 for heavy diesel engines (even 0w40 can be used in some car diesels).

the cst readings are why I switched from castrol. rotarys have to have really good film strenght oil to properly lubricate and cool,
I am also begining to believe that we may need better "crankcase" ventilation than we have.
Too much condensation being seen in the cooler areas, and how the hell is fuel getting in the oil? Makes you wonder. If fuel is getting into the oil then it has to past the side seals and side seal lubrication/cleaness is critical in this engine. May need a true vacuum line to the oil pipe and not just the one at the intake?
OD

Many pass the compression tests but is your engine closer to the minimum spec or right at the highest? I would say, have your car dynoed along with another 8 and see where you stand. If you are only putting down 160-170WHP then you know what will eventually happen.

Oh I have no doubt the engine will fail, the question is will it fail inside of warranty. I was about mid range on the last compression test. I was hoping to fail or be really borderline. You can count that I wont be using higher grade oils until then. I will be using what Mazda recommends. Plus a Mazda oil filter. That way they can't complain about it. I am following their guidelines. They want us using 5-30 (which is the new factory recommended oil) then so be it. Unfortunately I was around 108-112PSI for each rotor. Which well we know thats not low enough lol.

OD what oil?

I'm going to throw a wrench into the party here and I've got a hunch it will rub some the wrong way. Tough. Get over it. With the exception of mere curiosity on one occassion, I have never sent anything to Blackstone for analysis and never will. I think it is too easy to get caught up in the numbers and what each person THINKS they mean. Yes that means Blackstone or even BITOG too! I have gone as little as 1500 miles between oil changes and 10,000 miles between oil changes only topping off as necessary. Regardless of what a UOA may tell me, in the 5 RX-7's that I've had and hundreds of thousands of rotary miles that I have logged, I have NEVER once had a rotary engine failure. I have never had one that has had mileage or emissions suffer as a result of the oil. Was there ever wear inside my engines? Of course there was. Knowing it wouldn't change anything. Basically what I'm saying is send in for a UOA only for the curiosity and then throw it away and go about your regular oil change intervals with a good quality oil. Preferably with a good synthetic. Then relax. Don't worry. Enjoy your car.

^way stick a fork in this thread RG. That makes sense to me have driven many vehicles with least concern for oil and when to change them until I bought the 8. I just like your thought process and from other reliable sources I have read here I think many here over think the oil issue especially for us DD people of RX.