Arguments for heavier oils are based on the fact that hardly anybody ran 5W20 until the S1 Rx-8 and hardly anybody had bearing problems until the S1 Rx-8...

ask Kevin Landers (Rotary Resurrection) how many 100k+ mile 12A and 13B's he's torn down with better bearings than the typical 60k Rx-8

 

It's a bit too early to tell about 07-08 engines, and yes they changes on 09'.s because the delivery system was inadequate.

IMO it does not matter how much oil squirt/dribble.
Come in pre-Mix

 

Yes but to base it just on that is lame. There are so many factors (environmental, driving style, Gas used, oil used, etc.) that lead to engine failures. I seem to remember a lot of FD engine failures here in Texas back in the day but I don't think a Turbo engine should be compared to a non-Turbo one.

Also, if you increase the OMP output does that oil make it to the center of the seal? I still think premix is the best we can do in that aspect.

 

Yeah, the bearings would be still looking like new...

Almost ALL of the Guys who actually strip rotaries and have some knowledge from Age, are seeing and saying the exact same thing...Viscosity....

As is said, I think the "thin" oils are OK if you do more changes, but if you wait until scheduled Mazda Servicing..it is too long.

 

I wasn't even referring to FD's, what I meant was nonturbo engines (hence the 12A reference). Rotaries don't spin bearings generally speaking. That's a piston thing, or at least it was until the Renesis ran lower oil pressure and thinner oil.

 

And the owners of all those motors used nothing but high quality synethic 5w-20 at regular change intervals? How many of those motors had bearing failure?

If the failure was not sure to a lack of OMP injection (which the vast majority are) then normally an engine failure has a back story such as "I only add oil when the light comes on."

Who would these guys be?

So if the issue is the change interval and not the viscosity then what you're saying is the failure is on the part of the owner and not the viscosity. If you use a quality synthetic which can go 5,000 miles between changes then you would be fine.

Trying to base all of these claims off of the condition of a motor with 50k - 100k miles is nearly impossible. I don't know anyone that uses the same oil today that they used when they bought the car. People's driving habits change, their care of their car isn't done at the same time and so on. Unless you have a fresh motor using the same oil for 15k to 20k miles there's never going to be an end to this.

I have 6 quarts of 0w-50 sitting in my garage right now for whenever I get back on the race track. Since I run higher temperatures on the track then I do on the street that oil viscosity makes sense. Viscosity choice depends on application.

Would you run R-compound tires on the street? No. You don't need that grip so why spend the extra money and waste all that rubber?

Would you run race fuel on the street? No. Unless your car cannot run without it there's no need.

So why would you use oil that would work fine for the track on the street?

 

cool

 

Well, the bearing issue is only one part of the equation and may apply to this engine in the UK but not overall from the rebuilds I have seen. Some of the tear downs of blown renesis' have not had excessive bearing wear. Some have been excessive carbon, some (okay likely most) OMP related, some from various OIC's, some from overheating, some from not allowing the car to warm up daily, and some from just neglect. Like I have said, this engine is not for the average person as it takes special attention.

 

Funny you mention that. I was at the dealership a couple years ago picking up an oil filter, and I met a guy with a 91 nonturbo FC. He said he had about 210k on the original engine and talked about how he drove it everywhere and threw random crap in it all the time. Amazed by the mileage, I asked him, "What's your secret?"

his reply: "I always add oil when the light comes on"

 

Guess he is just lucky.

 

Well, even a broken watch is right twice a day.

 

When there has been talk of filing class action lawsuit on this forum for the failed engine problems. You think Mazda is dumb enough to give the lawyers the bullet to help them shoot'em in the back?

 

But parts that will "see" oil are mostly the same for the past 20+ years.

 

RG,
I add a bottle of Lucas UCL at every fill up. Does this qualify as "pre-mixing" in you well respected opinion or should I do more? (04 6MT, 86K reman @ 65K, 5W30, hot climate in summer)
Thanks,

LF'n8

 

Mazmart's Rick Engman is one of them. When they took apart my 110,000 mile engine that was well maintained they came up with the same conclusion.

 

Well now we're getting to specifics! This is a step in the right direction.

Yep your right, silly me. The fact that this car uses electronics that make previous ECU's look like pocket calculators, putting out about 1,500 more RPM's, having a completly different port configuration, different rotors and a host of other differences really isn't a big deal.

"Mostly" the same and being the same are two different things.

If offering up a single motor to end all debate is an accepted practice then I'll offer up my own car. I've got about 89,000 miles of daily driving, track time and autocross in probably one of the harshest environments temperature wise in the United States. I ran 20w-50 for maybe 6,000 miles of all that. 50,000 of it was RP 5w-30 and the rest has been using Mobile 1 0w-40 which is more or less a high 30w oil after the first 1,000 miles.

My motor has lost a bit of compression in the last 40,000 miles but I still managed to pull 192whp last February and based on the calculations we saw last weekend (despite us breaking SR Motorcars' dyno) I should be close to 195whp.

Factory motor, factory tranny, factory clutch...factory everything and its a 2005.

The point? Until someone can provide accurate testing data using fresh motor builds everything that is claimed here whether its from me or anyone else is going to be based on limited information with tons of variables. Telling people "use 20w-50 or else" is irresponsible when nobody has any basis to back it up other than their own experiences.

What has been presented, however, is a logical argument based on the physics of pressure, the fact that there is little differences in warm viscosity while huge differences in cold viscosity and the argument that your base stock of oil can have a huge impact on how well your oil holds up.

You might as well argue that horsepower is the only thing that matters in performance while completly ignoring brakes, suspension, weight, grip and a host of other factors.

 

are yall talking about the places on the housing right after the sparkplug hole? Thats not from lack of lubrication--yall know that--right?
OD

 

What do you speak of OD?

 

Flash,
The thread subject is actually about Bearing Wear seen once a failure may have occurred through the MOP-Apex Seal issues... lack of oil in middle of Apex.

As we know MOP has nothing to do with Eccentric Shaft and or rotor bearings, MOP oil does not even touch these areas.

Paul from Mazmart and Mr E, the guy who does the rebuilds has comment and seen this bearing wear, he also happens to have concerns about the engine oil viscosity. Kevin Landers is another..

Remember these pics are from a UK engine using 5W30 oil, and I happen to agree it is probably not an issue "IF" the owner changes out their oil before the scheduled service, and or time and or mileage.

 

THE MAIN TOPIC OF THIS THREAD ARE THE EXCESS WEAR SEEN ON BEARINGS....PRE-MIXING DOES NOT TOUCH ANY BEARINGS...

FOR THOSE WHO THINK THE RENESIS IS "SPECIAL" AND DIFFERENT TO "OTHER" ROTARIES THIS IS NOT CORRECT. On This Subject Matter.

HERE IS A LIST OF ALL THE MAZDA PARTS BY PART NUMBER USED IN THIS BEARING DISCUSSION
AND THEIR APPLICATIONS TO WHICH MAZDA ROTARY MODELS AND THEIR YEAR.

THIS IS NOT 'HEAR SAY' OR A 'THOUGHT' IT IS REPLACEMENT MAZDA PARTS FACT. (Sorry I am not Yelling) From MMC Parts File.

SERIES 1 AND 2 RX-8, OR MY 2004-2010, THEY BOTH USE THE EXACT SAME PARTS.

************************************************** ************************************************** *******************
GENUINE MAZDA PART NUMBERS...

ROTOR BEARINGS..................... #N3A2-11-B11 (Qty2)...used in RX-8 , and 1992-2002 FD* RX-7's .

STATIONARY GEAR BEARINGS....#0820-10-502B (Qty 2).used in RX-8 (4 port), 1985-89 FC RX-7, 1978 SA (FB) RX-7,1969 R100*10A, RX-2,3,4,5.
STATIONARY GEAR BEARINGS....#NF01-10-E04 (Qty 2)...used in RX-8 (6 port), 1992-2002 FD* RX-7.

ECCENTRIC SHAFT OIL JETS......#N326-11-D11 (Qty 2)...used in RX-8, 1985-89 FC* and 1992-2002 FD RX-7.
ECCENTRIC SHAFT O J SPRING..#0839-11-412 (Qty 2)....used in RX-8, 1971 RX-2*,3,4,5,7.
.
ECCENTRIC SHAFT PELLET........#N326-11-D15 (Qyt 1)....used in RX-8, 1985-89 FC* and 1992-2002 FD RX-7.
ECCENTRIC SHAFT P SPRING....#N326-11-D17 (Qty 1)....used in RX-8, 1985-89 FC* and 1992-2002 FD RX-7.

* After Model means the Model Originator (Black Highlighted) of that Part.

ALL Rotaries before the 1985 FC RX-7 did not have an Eccentric Shaft Heat Pellet.
************************************************** ********************************************

HERE IS A 1973 MAZDA RX-3 PARTS BOOK SHOWING THE SAME 0820-10-502B STATIONARY GEAR BEARINGS USED IN A 4 PORT 'RENESIS' RX-8



AND THE SAME BEARINGS SHOWN IN A SERIES 1 RX-8 Parts File...

 

Forgot to add..

Although there is a difference in Stationary Gear Bearings between the 4 ports (#0820, 40 year old ones) and the 6 port (#NF01, 17 Year old ones), the Eccentric Shafts are still the same for Both series RX-8's. The only difference between the two Stationary Gear Bearings in design are the 6 port ones have a small round hole in them for a "Stopper Pin" (#NF01-10-E09 from FD RX-7) which screws into the Bearing Gear Housing and Bearing.

The 4 ports and all other rotaries R100, RX-2,3,4,5,7 (SA or FB, FC) use the same Bearing (#0820-10-502B) but don't use/require the stopper pin.

 

Saying this engine failed because of oil viscosity alone after looking at that wear is like saying a PC crashed because of a power peak after looking at a log that says the PC crashed.

There's MANY factors and variables, most of all, the user. I don't think you could even say something sure about oil wear and needs and problems without testing 10+ engines with the exact same wear and usage for a year, like Easy I guess were onto, but two wouldn't be enough imo.

That's why this is a difficult discussion and why there's no conclusions ever, and I think all "the debate is over" is bullshit. No offense

 

the marks below the sparkplug hole is due to the crack in the sparkplug area. the crack causes an uneven surface on the face of the housing and the apex seal will "leak" and have uneven wear impact in that area. SO I have been told and shown by both Cam and Mr E.
Sorry for the thread jack!
On bearings---on an engine teardown of mine a few yrs back --the front bearing was to the copper on one side. It had no overheating issues and it ran on RP 10w/30 from approx 20K miles forward. It had approx 50K on it at teardown.
Excluding heat/overreving, improper warm up (a lot of people dont realize that even after the oem coolant temp gauge shows fully warm , the oil is only around 140F, it takes another mile or two to get it to 160+) ,oil starvation due to low levels, lack of maintainence, I know of no other cause than lack of proper oil?
The viscosity of oil breaks down quickly, especially if the base stock is not of high quality--at least that is what is showing on oil analysis tests.
Do we have a lot of fuel contamination in our oil?
OD

 

Fuel contamination can be an issue but it should be a lot smaller than in the previous rotaries, this should also be the reason why mazda redesigned part of the oil scrapers etc

 

We got the lightest Rotor outa ther whole 13B/12A family. It also has the best (as of 2003) Geometry.

We got the best balanced and lightest E-shaft.

Using the same Rotor bearing and Stationary for the past 20+ yrs.

Same Oil pump, even the chain is the same.

The only difference I see so far is, 13B-MSP got the highest NA power from its 10:1 compression and a "brand new 5w20" oil recommendation.

IN the old days, Mazda gives ya a chart and say "all of them works with this and this temperature", people are too dumb to read charts, so Mazda threw the "one size fits all" card out and "hey, we think you should use 5w20"

But does one size really fits all? Dont think so.

In fact One size fits all usually fails. its either too big or too small.

Mazda shot themselves in the foot over this one, if they recommend at least 5w30 (it still suck btw) in the first place. I think lots of the engine failures could have been prevented.

Im thinking, will a Cryogenic treatment prevent these bearing problems ? I know someone sells stationary gears with that treatment.