Documented Engine tear down by Hungarian Mazda dealer
 

I just curious, what language this is and if anyone speaks it. I came across it randomly.

http://www.mazda-auto.hu/mazda-rx-8-...-expanzio.html

Hungarian?

There's something called google translation out there.

It's hungarian. If you're using Google Chrome it'll automatically ask you if you'd like it translated to english.

^^^ Google chrome ftw!!

I'm using Chrome. Translation is awesome! I visit a lot of non English sites thanks to Chrome.

I tried chrome, it sucked, images on this site often would not load, etc. and doesn't work on several business sites I have to visit. But I guess I'll try it for this purpose.

The picture pretty much spoke for itself.

The bearing is done, e shaft looks fine. Rotor carbon normal, rotor housing has heat spot which is normal for stock engines with no fin mod plus I see chrome flaking which means it's bad.

I'm pretty sure the engine was run with thin oil cuz of the wear on bearings.


Oh btw, chrome sucks, it doesn't work with lots of sites, it crashes and all the fake fast loading annoys the crap outa me

Yeah i'm just curious what they are saying about it on a Mazda site. Google chrome is still trying to translate it..........................

Works fine for me. No issues on any sites I use. I also have my tweaked very heavily. Lots of plugins and settings tweaks. But, I'm also the guy with his PC overclocked as far as it will go, on everything. Nothing stays stock for long on my rig. lol

off topic : my comp is fast enough takes 10 seconds to load windows, that's good enough for me, no OC needed :)

What's the translation for "foregine" ?

OC has nothing to do with that. But, I can crack 41,000 points on 3D Mark Vantage. I do this stuff for a living and a hobby.

http://farm7.static.flickr.com/6199/...cb067391_b.jpg

^My mind is blown.

I have a custom rig too, but it was built for me. Haven't had the time to really learn near as much as I'd like with computers, it's a shame.

I'm interested as to what plugins you're running myself. It's taking quite a bit to translate for me, as well.

I used to do that, but now work and cars and family and my girl and other bs is keeping me busy all the time. so I was like ahh I can drop this, don't need the biggest water pump to cool that sucker down enough so I can push it to 6GHz.

now I'm more focus on bringing home bread n butter n money to run my rotary, lol

Google translate still can't translate it in Chrome. Like I said, Chrome sucks. If it works so great for you can you just translate it and copy it here?

It's a long article about an engine torn down after 100,000 kms so about 63K miles, with oil changes done only every 12.5K miles ...
Hungarian is my native language, so I can translate it for you if automated translation methods are not sufficient (which is probably the case) - but it will take some time :)
I'll try to take time tonight and do the translation.

By the way, the web site is of an official Mazda dealer / service in Hungary who are considered one of the most knowledgeable dealers over there about the RX-8.

Thanks man!! No rush. Oil changes every 12,000 miles?

Completely off topic (i apologize 9k):
Overclocks don't mean a lick of shit if you can't back them up with a 24hour prime95 run on each core ... but i am sure you knew that.

weird. chrome and google translate had no issues whatsoever doing the translation on my stock 3 year old sony vaio nw

RX-8 13B-MSP RENESIS 100,000 km.
Date: 2011-05-05
Mazda RX-8 rotary engine disassembly.

Right in the middle of a cut in a Mazda RX-8.1 million kilometers mileage, and service documentation that, unfortunately, only very rarely, done 20,000 miles per oil change. Disassemble the engine, let's see how wearing the rotary engine parts authoritarian past ordeal!

Rarely straightforward.

Of course, before anyone would think that Mazda brand experience just in our service to collect was removed and disassembled in a Mazda RX-8 engine, I must say that the car engine problems have occurred in the past. The cold immediately after the initial warm-up wankelt could not be stopped to start the following hypothermia. The car owner had told us of "collapse" is also used catalytic converters the car, just not warm to the aforementioned issue, prior to departure. The possible consequences into account and all related options after exclusion (such as spark plugs, coils, etc ...) only the left engine failure option. This is a somewhat weak power output has been confirmed.

A breakdown of the inside of the engine before it is worth taking a look at the oil delivery system jets that make up the engine oil leaks from the ventricles (apex, corner, side) serve to cool.:
http://www.mazda-auto.hu/userfiles/m...panzio_mop.jpg
The nozzles are perfectly clear, and 100 000 km to 20,000 km by Mazda changed Dexelia 5w-30 motor oil after use. Of course it would be surprising if they were contaminated, because the engine "vacuum phase" of the trochoid houses are located, so the effect of vacuum them departing air-oil mixture to prevent deposition of dirt, oil, irrespective of quality.
They are not dirty.

It is also worth examining the breakdown of the engine before the 231-horsepower RENESIS 13B-MSP-cylinder intake control valves (APV) as well. Despite the 100,000 km mileage, remained relatively pure components, were still very far from the accumulated coke may result from dysfunction. The picture is unfortunately only after the cleaning is one of the control cylinder, so that the reader have to believe me.

http://www.mazda-auto.hu/userfiles/m...o_expanzio.jpg

The first eccentric shaft bearings.

Turning the engine start sequence, the first zárófedéllel The inner surface of one side to the first planetary piston housing when stored. More precisely, this positioning of the lid is fixed gear and the eccentric shaft bearing housing.
http://www.mazda-auto.hu/userfiles/m...zio_kft(1).jpg

The house is inside the eccentric shaft can be seen in plain bearings. The plain bearings operating principle is based on the bearing pressure bejutatott oil, forming a film on the shaft and prevents metallic contact between the bearing housing. The shaft and the bearing housing after the substitution of oil between the oil pump is supplied by the engine oil provides. The higher the speed of the shaft, the more oil replenishment is required, since the faster rotating axle load is not even squeeze out more oil to the bearing housing. The bearings agitated olajnyomásból the oil quantity can be inferred. More pressure = more oil. Details írásainkban MOTOR OIL, HERE and HERE.

http://www.mazda-auto.hu/userfiles/m...anzio_kft2.jpg

As can be seen in the previous two pictures, unfortunately, this is a very plain bearings are worn condition. Internal combustion engines are rarely encountered such abnormal extent, even after not much more mileage. The 13B-MSP RENESIS rotary engine is often the case unfortunately. This type of wear is not really justified by any operational condition, or immediately after a Cold Start ruthless drive, or persistently low engine oil usage, inadequate cooling ... But even these exceptions are not really the truth, because one engine wear can have similar experience, and every owner is not liable to make mistakes, and the construction in this area should be protected against errors. Unfortunately, so has to be said to be primarily due to the design defects of this kind of wear problem. This is even more puzzling, as a plain bearing oil supply to non-specific "rotary thing" - such as leaks Lubrication -, "" just scale should have the lubrication system and / or components, but more about that later still more, the eccentric shaft bearings at the rear.
The first planetary piston housing.

Going-based rotary motor on our planet we reach the first piston (rotor) house. Clearly, the state is not primarily a visual engine determines it to be measured! Nevertheless, as the following pictures show, the first planetary piston sliding surfaces of the side or apex of the orbit leaks tax trochoid surface is surprisingly good shape for the distance 100,000 km of operation, and maintenance in spite of the weak.

http://www.mazda-auto.hu/userfiles/e...o_expanzio.jpg

Számolgassunk a bit! 50 km / h average speed of 100,000 miles, 2,000 hours of operation means that an average of 3,000 res eccentric shaft revolutions per minute, calculated as 360 million units total reversal of the eccentric shaft. At exactly three times in less than a complete revolution of the rotors have been, or 120 million units, as the eccentric shaft one full turn of third rotor speed to play. The trochoid sliding surface given the length of this means that the apex of the leaks have been nagyjából100000 km to the surface. Although the average speed and average speed data only teorikus, how interesting that the apex of the same car for leaks gyakolatilag futásteljesítményűek.

http://www.mazda-auto.hu/userfiles/e...panzio_kft.jpg

This might be a stupid question, but I admit to having no experience in a rotary teardown, but in theory, should there be caked on oil below the apex seals like that? I thought the side seals were there to prevent that from happening?

Thanks. Tough read :lol:

A 2.5-liter gasoline engine piston Mazda6 in the same calculated average values ​​of the piston rings during this period shall be: 72000 km on the cylinder surface .. This is roughly 30% less than the load, lubrication differences (to the detriment of the rotary engine), not to mention now. 2,5 In addition, a relatively long stroke resources, a short-stroke engine has less mileage of the rings.

http://www.mazda-auto.hu/userfiles/elso_trochoid.jpg

RENESIS-our (renezisz) in the first trochoid rotor housing ("Oval") orbits, and the sliding surface shows a rather significant wear at the edges, the edges partly be attributed to increased heat load on the side exhaust ports due. This is so despite the fact that the engine oil cooler is to arrive in larger quantities in the picture above shows two tiny black hole.

http://www.mazda-auto.hu/userfiles/m...o_expanzio.jpg

The picture shows one of the first planetary piston housing oldalfedelének exhaust openings can be seen. The previous Mazda wankeleken peripherally located after the exhaust ports, the RENESIS introduced via side-mounted slot One aim of the special shape of the lateral and corner seals éltömítéseket clean the carbon deposits. Effectiveness of the operation of the vent deposits at the narrow end is visible. Why or less carbon-like material deposited in the engine, or perhaps more long-term loads in intermittently left the deposited amount. A small deposit may also be evidence that these parts is really a gasoline combustion of hard coal deposits in the origin can be rather small compared to the volume of the unit volume of combustion of motor oil. Apart from a detailed technical explanation, if it originated from the oil deposits in the engine, the engine oil change in our more neglected in terms of deposition should be.

The first rotor (piston planet) the other side of the side exhaust port is also quite clear:

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

One could say that 900 degrees Celsius there is little chance of engine oil, but it seems not only to oil combustion products, but much greater quantities are generated from the combustion of gasoline-like carbon deposition can not accumulate. The picture above is clearly visible in the side sliding surface is quite normal, "porous" (right olajmegtapadás) surface.

The first planetary piston, ie, the first rotor

The authoritarian Wankel engines, so the Mazda RENESIS 13B-MSP in the planet's eccentric shaft piston trajectory of ham, and have presented in this article defines positioning gear, not the trochoid housing "oval" of his career. The planet piston (rotor) is not physically touch the surface of the sliding housing trochoid, only put into them in contact with the sealing surface trochoid or lateral ventricles side boundary with lids.

Thus, the rotor principle not kophat if the bearings, positioning the gear and the eccentric shaft bearings does not allow for "hanging out" for the incorrect path. But before megörülnénk this news, the rotor can spit, bearing still intact as well. The rotor seal is located, whichever is first apex of the leaks continued movement on the rotor vályatukban trained. The seal between the nest and the combustion products, the effect of movement of seals, gaskets and worn under the blows of the tolerance of the koptathatják tömítésfészkek width. However, after 100 000 km of the planet, this piston in this respect is re-usable state.

The rotor friction bearings (picture above) is considered in good condition, compared to the previously discussed threadbare eccentric shaft bearings. The side "oil seals" and the intake and exhaust ports together-working to prevent the sealing ring (cut off) also remained in good condition, without substantive changes, easily moved gyűrűfészkeikben.

It is because of these planets piston kokszossága not be fooled by anyone! The important points were not igazás "problem" that deposits on the rotor and the assembly during the current engine oil coke is "rondítja the photos." Although the positioning of the gear is not in place, clearly visible in the picture above (rear rotor, not the first), the importance of nearly 4 kg of rotor mass balance and precise guidance of, for example, by an eccentric shaft bearing is worn, may be affected.

Apex, heel, lateral leaks (rotor 1).

We have reached our engine piston of the first planetary éltömítéseihez apex of the corner seals and side éltömítésekhez for which data sharing is now wearing a nice reader.

A piece apex bolygódugattyúnak three leaks, which are located on the vertices of the rotor and the housing trochoid sliding ensure the tightness of the chambers, the six-cylinder corner seals, and also six éltömítéssel side together.

Mazda officially allowed to wear 1 mm thickness from the apex leaks, which they consider an average of around 240 000 km occurs. This figure is certainly not considered légbőlkapottnak as engine for the first bolygódugattyúján all three apex seals 0.5 mm et worn on the 100,000 km of use, and as you decrease the weight and thickness (a rounded crown), wear and tear slow down somewhat. Lateral surface is also measured in the up and down movement due to wear, although this is also not assumed a critical objective.

The image above lateral compression leaks size remained virtually default value 100000 km running performance after the first bolygódugattyún. Tömítésfészekbe prevent constipation caused by the deposition of the wedge-shaped éltömítéseknek training is that it seems it worked perfectly, because each of the six leaks freely moving nest.
The second planetary piston housing.

The second rotor on one side of the middle intermediate (intermediate) is bounded by housing, which is the opposite side of the rear rotor of the first timber is running. In the middle section, as opposed to two végfedéllel, not embedded in the eccentric shaft bearings.

Mazda Rx-8 13B-MSP köztes ház csúszófelület.
http://www.mazda-auto.hu/userfiles/m...zio_kft(1).jpg
The first planet in relatively good condition, piston against the side surface of the cover image is visible, the exhaust port is fairly worn around the second rotor side seals sliding surface of the intermediate casing. But the picture also shows that the exhaust port "deposit removal" function right corner holding a little saturated. It is seen from the first rotor.
http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

In the meantime, the home side surface of sliding surfaces of the rotor housing trochid continued again 'dark' image as the house was the first rotor. The surface is highly uneven in some places show wear and scrapes. Yet one of the most worrisome gyertyanyílástól (Leading) the initial transverse crack.

Mazda RX-8 13B-MSP trochoid felület.

The second chamber rear wall of the sliding surface of the lid which last too many new things I can not say. Not as healthy as the first chamber, but the exhaust port deposits are also not insignificant. Overall, the wear can be stated that the second planetary piston housing is much higher thermal load has been exposed as the first, but the strong suspicion that sometimes too rapid temperature change is "suffering" components. Instead, it is not sufficiently gentle warm-up pose. Probably the trochoid housing is therefore allowed the surface of the narrowest part of it.
The second piston planet, that is, the second rotor

This writing covered Mazda rotary engine 13B-MSP-based resource bolygódugattyúja second - as the first rotor - újrafelhasznáható 100,000 km of state until after the work performed. The planet tömítésfészkeinek piston size remained within the tolerance of the seal movements have already been discussed so far have not caused excessive wear. The motion for stay, the rotor was moving freely in each nest seals, gaskets deposits due to "grab" could not be established.

The eccentric shaft csapágyazásánál much larger planet with a diameter piston sliding bearings remained in relatively good condition, but it is not so much a re-run with raknánk used motor bearings, if you were to take place. The rotor gears are also not visible signs of wear. It seems that these parts of the engine oil was able to cope with the increased heat load.

Apex, corner, side leaks, the second rotor

This is probable but greater heat load in the apex éltömítéseken clearly noticeable if we compare their wear rate of the first "triangle" of the same piston seals. The rear rotor for all three apex éltömítésének 0.1 mm smaller in height than the first rotor seals can be measured the same values.

The side virtually no measurable wear, leaks, and their distance from the corner seal is below the tolerance limit. The springs also seals remained in good condition.

The eccentric rear axle bearings.

The beginning of this article has been viewed, how worn the eccentric shaft (the main axis of the rotary engine), the first surface of the plain bearing. Unfortunately the same can be said of the other bearing axle of the rear cover which is bolted to the positioning of the gearbox. It seems eccentric to the axis of movement during the RENESIS sometimes csapágyaiból squeeze out more oil than the oil supply coming into them. The times and temperatures are in speed, or even ruthless about start-up conditions. Rádásul bearing such attrition after several replacements for oil would be needed.
http://www.mazda-auto.hu/userfiles/m...rga_istvan.jpg

The higher the temperature of the bearing, and the higher the speed, the higher the oil pressure would be required to provide sufficient quantities of motor oil can circulate through the bearing. Many people believe that a higher viscosity oil can be warm side of the gap, but the thicker the oil the same pressure, flows more slowly, so that less oil is less able to cool the bearing. Consequently, the bearing temperature increased more in the thinned engine oil, which slowly comes to succession. Thus xxw-40-inch or 50-xxw motor oil, we do not really advance.

In fact, it may be to say that the Mazda engineers have created the largest-speed rotary motor known, the lowest ever value of the maximum oil pressure (5.1 bar max.), To mention only the basic anomaly. In addition, it is just one part of the problem. Of course, we have applied some balm mean mazda auto-I Phase II and mazda-auto. phase, which is a step forward in solving complex problems. Click here to read these types.
The eccentric shaft or the rotary main shaft.

The eccentric shaft is practically the main axis of the rotary piston engine equivalent. The eccentric shaft to get the rotors sonkáinak planetary motion of the drive clutch for rotary motion. The eccentric shaft slide bearing ensures the rotors of oil supplies, but also cool the inside of the rotor away from the engine oil (oil jet) provides.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

If a unit of speed, more oil flows through the center of your engine oil zási eccentric shaft, the more oil is cooled by the bolygódugattyúkat. The shaft wear is not so typical, since the bearing metal is softer, more shock to the axle should be checked, but the shaft was found to be good.

I prefer new.

The all-new car factory (Japan only) engine was assembled, because the new owner's expectations based on a minimum of 100 000 km of new power sources seamlessly meet. This is all the chances, as it is now at 10,000 per km will be replaced with engine oil, which is now a fully synthetic 0W-30 multigrade lubricant index will be. Shorter oil change intervals, or fully synthetic oil "stable" the steadfastness of the next oil change is itself a great step forward. The hypothermia less visszadermedő lower cold side labeled motor oil will also assist the eccentric shaft átolajzását faster startup, which in this case the eccentric shaft bearings the load is reduced. This further step up the mazda auto-II phase is immediately entered into the new engine.

The RENESIS resilience of matching, greater quantities of oil transportation (motor) also I. applikált mazda auto- phase provides. In addition, the engine break-in can now provide much help to the provision of life. The first 750 km up to 3000-3500's and 1000 km in some cases up to 4000 rpm-res pörgetve become the new engine.

http://www.mazda-auto.hu/userfiles/m...rga_istvan.jpg

There is also a private opinion, I note that quite a number of Hungarian Mazda RX-8 test car began his career as a serious and, unfortunately, information, raise awareness in the absence of these cars had no chance for the aforementioned gentle entrance. Respect to the exceptions of course.
Old and new.

The resulting compression of this problem is likely to warm the house back trochoid-wear damage caused by the previous engine. In addition to rapid changes in temperature cause cracks, which could cause even gyújtáskimaradás, warming harsh, or both. The trochoid housing replacement or renovation of a professional seal all necessary costs, machinery work is carried out, and the total amount of fees that kick, which is almost a complete new engine factory price. Moreover, in this case is still in a restored engine will (some of the less worn, but worn (!!!) parts), so I assume needs no explanation, that such an engine is not in the same life expectancy as a completely new wankeltől. Varga Stephen (20-9577080)

WARNING! Other rumors in Europe only in Japan, assembled in a complete new factory distributor of Mazda engines. These engines are not renewed, which is based on the engine number is clearly justified. Factory reconditioned engines exclusively for the North American distributor representing Mazda, but they can not be imported.

This is a literal translation, but some of the concepts got "lost in translation".

The ideas for the failure aren't much better than blackstone, but I think most of us have seen pics like these.

Final translation: Renesis kaput!

Owner ran the piss outta car on too long an oil change and a too light weight oil, didn't premix, and ran with misfires.

It looks like they are saying a xw30 is preferred over xw40 or xw50 to me.

The scary thing is that apparently, that's the Mazda-suggested oil change interval over there... :eek:

Translation
 

OK, here is the text in a hopefully more readable format than the Google translation. Mind you, I probably mistranslated a few things :D:

RX-8 13B-MSP RENESIS 100,000 km.
Date: 2011-05-05

Mazda RX-8 rotary engine disassembly


Let's jump right in the middle: we've got a Mazda RX-8 with 100,000 km on the odo. According to the maintenance log, the oil change interval was unfortunately pretty long, only at every 20K km (12.5K miles). Let's tear down the engine to see how the rotary engine parts coped with the challenges.


Rarely obvious

Before anyone would think that our dealership would simply remove and disassemble an RX-8 engine just for the sake of gathering experience, I have to tell that there were problems with the motor of this car earlier. The engine always started fine when cold but could not be started again until it was left to cool down. According to the owner, he kept using the car even after the cat collapsed, which was shortly before the mentioned warm start problems appeared. Considering the possible consequences of all this, and eliminating other potential problem sources such as spark plugs and ignition coils, the engine failure remained the only plausible explanation. This was confirmed by the somewhat decreased power output as well.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Prior to cracking the engine open, it is worth to take a look at the oil pump system's nozzles that provide the oil to cool the seals (apex, corner, side):

http://www.mazda-auto.hu/userfiles/m...panzio_mop.jpg

The nozzles are perfectly clean after 100,000 km, using 5W-30 Mazda Dexelia oil that was changed every 20,000 km. Of course it would be surprising if they were contaminated, because they are located at the engine's "intake phase" on the trochoid housings, so the vacuum-driven departing air-oil mixture prevents deposits, irrespective of the oil quality.


These aren't dirty either

Before the breakdown of the engine, it is worth examining the 231-horsepower RENESIS 13B-MSP's auxiliary port valves (APV) as well. Despite the 100,000 km mileage, they remained relatively clean, still very far from having issues caused by accumulated carbon. The picture was taken unfortunately only after cleaning one of the control cylinders, so the reader will have to take my word for it.

http://www.mazda-auto.hu/userfiles/m...o_expanzio.jpg


Eccentric shaft front bearing

Turning to the engine, we'll start with the front iron, covering the first trochoid. To be exact, with the stationary gear and eccentric shaft bearing's housing.

http://www.mazda-auto.hu/userfiles/m...zio_kft(1).jpg

Inside we can see the eccentric shaft's front bearing. These kinds of bearings work based on the principle that the injected pressurized oil builds a layer preventing metal-to-metal contact between the shaft and the bearing housing. Oil is supplied by the metering oil pump. The higher the revolutions of the shaft, the more oil is needed, since the increasing load on the faster spinning shaft causes more oil to be displaced from the bearing housing. We can estimate the amount of the oil based on the oil pressure. More pressure = more oil.

http://www.mazda-auto.hu/userfiles/m...anzio_kft2.jpg

As it can be seen in the previous two pictures, this bearing is unfortunately in a seriously worn condition. We rarely encounter such abnormal wear in internal combustion engines, even after much higher mileage. In case of the 13B-MSP RENESIS rotary engine, this is unfortunately quite common. This type of wear is not really justified by any operational condition, only perhaps by abuse after a cold start, or persistently low engine oil level, inadequate cooling ... But not even these circumstances explain it, because we experienced similar wear in several engines, and not every owner will make the same mistakes. Besides, engine design should protect against such errors. Unfortunately, the wear appears to be primarily due to design defects. This is even more puzzling, as a plain bearing's oil supply is not rotary-specific, unlike seal lubrication. Instead, proper scaling of the lubrication system and parts would have been necessary – but more about that later still, when we talk about the rear eccentric shaft bearing.

The front rotor housing

Continuing with our Wankel engine, we arrive to the front rotor housing. Obviously, the condition of an engine cannot be assessed by just eyeballing it, it has to be measured. Nevertheless, as the following pictures show, the front rotor's sliding surfaces or the trochoid are in a surprisingly good shape despite of the 100,000 km mileage and subpar maintenance.

http://www.mazda-auto.hu/userfiles/e...o_expanzio.jpg

Let's do a bit of math! 50 km/h average speed for 100,000 km means 2,000 hours of operation. If we calculate with an average eccentric shaft RPM of 3,000, this means 360 million revolutions of the eccentric shaft. The rotors completed exactly three times less revolutions, or 120 million, since we have 1/3 rotor revolutions for each full turn of the eccentric shaft. Considering the length of the trochoid sliding surface, this means that the apex seals traveled about 100,000 km. Although the average speed data is only theoretical, it's interesting that the apex seals completed practically the same distance like the car itself.

http://www.mazda-auto.hu/userfiles/e...panzio_kft.jpg

In case of the piston engine of a 2.5 liter Mazda6, the piston rings travel about 72,000 km when calculating with similar averages. This is about 30% less, let alone the load and lubrication differences (a disadvantage for the Wankel). On top of that, the 2.5 liter is a relatively long stroke engine, so in case of a shorter stroke engine, the piston ring travel is even less.

http://www.mazda-auto.hu/userfiles/elso_trochoid.jpg

In our RENESIS, the front trochoid and it's surface shows a rather significant wear at the edges, which can be attributed to increased heat exposure on the sides, due to the side exhaust ports. This is so despite the fact that most of the cooling engine oil arrives here as well, through the tiny holes visible on the above photo.

http://www.mazda-auto.hu/userfiles/m...o_expanzio.jpg

The picture shows the front rotor housing cover's exhaust port. Following the peripheric exhaust ports on previous Mazda Wankels, the shape of the side ports introduced on the Renesis was chosen to clean the side and corner seals of carbon deposits. Their effectiveness is visible from the deposits at the narrow end of the port. This means that either there were less carbon deposits in this motor, or they were blown out due to regular high load operation. The small amount of deposits may also be evidence that they originate from the fuel instead of burning of the rather small amount of the engine oil (compared to the overall volume). Apart from a detailed technical explanation, if the deposits originated from the oil, then there should be more of them considering the neglected maintenance of this engine.

The front rotor housing's other exhaust port is also quite clean:

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

One could say that at 900 degrees Celsius the engine oil has little chance, but it seems neither oil combustion deposits, nor carbon from gasoline combustion can accumulate, even though the latter is present in much greater quantities. The picture above clearly shows that the side sliding surface is quite normal, “porous” (better oil adhesion).

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg


Front rotor

In Wankel engines, so in the Mazda RENESIS 13B-MSP as well, the rotor's trajectory is determined not by the trochoid's oval track but the eccentric shaft and the already introduced stationary gear. The rotor doesn't physically touch the trochoid surface, only the seals get in contact with it and the side covers.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Thus, in principle the rotor should not wear, if it’s plain bearing, stationary gear and the eccentric shaft bearing keep it on the correct path. But before we get excited hearing this, the rotor CAN wear, even if the bearings are intact. The rotor seals, especially the apex seals are constantly moving in their grooves. Combustion deposits between the seal and its grooves, the result of seal movements, and the worn seals can increase the width of seal grooves exceeding the tolerances.
Despite of all this and the 100,000 km mileage, this rotor is in reusable condition.

http://www.mazda-auto.hu/userfiles/m...o_expanzio.jpg

The rotor plane bearing (picture above) is considered in good condition, compared to the previously discussed eccentric shaft bearings. The side oil seals and cut-off seals also remained in good condition, without substantive changes, and can be easily moved in their nests.

http://www.mazda-auto.hu/userfiles/w...panzio_kft.jpg

The caked-on carbon on the rotors shouldn't fool anyone! There are no problematic deposits at the significant locations, plus the view is made worse by the motor oil dripping onto the carbon during engine disassembly. Although the positioning gear is already removed, on the above photo it is clearly visible how important is the precise guidance and balancing of the rotor that weighs almost 4 kg. This can be significantly affected by a worn eccentric shaft bearing.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Apex, corner and side seals (rotor 1)

We arrived to the front rotor's apex seals, corner seals and side seals. I will share the measured wear data with the reader.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

A rotor has three apex seals, located at the tips of the rotor. Sliding over the trochoid surface of the housing, they provide chamber tightness together with the six corner seals and side seals.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Mazda officially allows 1 mm wear of the apex seals which, according to our estimate, occurs at about 240,000 km mileage. This is certainly not random data, since we measured about 0.5 mm wear in 100,000 km at our front rotor. As their mass and thickness decreases, seal wear also diminishes to a certain extent. Wear from their constant up-down movement can also be measured on their lateral surface, although this doesn't reach critical level either.

http://www.mazda-auto.hu/userfiles/m...anzio_kft1.jpg

The above pictured side seals of the front rotor practically retained their factory dimensions after 100,000 km. In order to prevent deposits in the grooves that can cause the seals to get stuck, the seals have a wedge shape which appears to have worked perfectly. All six side seals can move freely in their grooves.

Rear rotor housing

The rear rotor is bounded on one side by the intermediate housing. The front rotor’s rear surface is sliding on the opposite side of it. Contrary to the front and rear cover, the eccentric shaft has no bearing here.

http://www.mazda-auto.hu/userfiles/m...zio_kft(1).jpg

Compared to the front rotor covers that are in relatively good condition, the rear rotor’s sliding surfaces are quite worn as it can be seen on the photo, especially at the exhaust port area. At the same time, there are relatively little deposits in the right corner of the exhaust port. We could already see the same at the front rotor as well. This corner’s purpose is to prevent forming of deposits.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Similar to the intermediate housing surface, the condition of the rear trochoid is also worse than the front. The surface is highly uneven in some places showing wear and scrapes. Yet the most worrisome is the transverse crack at the leading spark plug hole.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

The second chamber’s rear cover surface doesn’t bring a lot of news. It is not as good as in the front, but exhaust port deposits are not significantly present here either. Based on the wear shown, we can conclude that the rear rotor chamber was subject to definitely higher thermal load than the front, but it’s also strongly susceptible that occasionally, these parts were suffering from too quick thermal changes. This may indicate not sufficiently careful warm-ups. Probably that’s the reason for the trochoid “giving in” at the point where it is the thinnest.

Rear rotor

The rear rotor – similarly to the front – remained in reusable condition after 100,000 km. The seal grooves are within tolerances, and the already discussed seal movements didn’t cause problematic wear so far. No seal was stuck due to deposits.

http://www.mazda-auto.hu/userfiles/m...zio_kft(1).jpg

The rotor bearings - that have a much larger diameter than the eccentric shaft bearings – remained in relatively good condition, although we still wouldn’t rebuild a motor with this mileage utilizing used bearings like these. There are no signs of wear on the rotor gears either. Apparently the engine oil managed to keep up with the increased heat load in these areas.



http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Apex, corner and side seals, rear rotor

The probable higher heat load is clearly visible on the rear apex seals, compared to the front. All three rear apex seals are 0.1 mm shorter than the front counterparts.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

Side seal wear is virtually non-measurable, and their distance from the corner seals is also within tolerances. Seal springs are in good condition as well.

http://www.mazda-auto.hu/userfiles/w...o_expanzio.jpg

Eccentric shaft rear bearing

At the beginning of this article we saw how much wear the eccentric shaft’s front plain bearing surface sustained. Unfortunately the same can be said about the rear bearing that’s attached to the rear cover, together with the stationary gear. It seems the eccentric shaft of the Renesis sometimes extracts more oil from its bearings than the supplied volume. By “sometimes” we mean temperature or revolution spikes or even careless warm-up. On top of that, such bearing wear would require even more oil being supplied.

http://www.mazda-auto.hu/userfiles/m...rga_istvan.jpg

The higher the temperature of the bearing, and the higher the RPM, the higher oil pressure would be required to provide sufficient quantities of motor oil circulating through the bearing. Many people believe that higher viscosity oil is the solution, but the thicker oil flows slower at the same pressure, so that less oil is less able to cool the bearing. Consequently, the increased bearing temperature thins out the oil, which is supplied too slowly. Thus the usage of xxw-40 or xxw-50 motor oil doesn’t really offer sufficient help.

http://www.mazda-auto.hu/userfiles/m...rga_istvan.jpg

In fact we may say that Mazda engineers have created their highest RPM rotary motor ever, with the lowest ever maximum oil pressure (5.1 bar max.), and this is just the basic anomaly. In addition, this is just part of the problem. Our phase-I and phase-II solution provides the first steps to eliminate this complex issue.
(This is basically their service offering that increases oil pressure by a modification, as far as I understand)

The eccentric shaft (or rotary main shaft)

The eccentric shaft is practically equivalent to the crankshaft of the piston engine. It converts the planetary motion of the rotors into rotary motion that drives the transmission. The eccentric shaft provides the oil supply to the plane bearings of the rotors. The rotors are also cooled by the oil distributed by the eccentric shaft’s oil squirter.

http://www.mazda-auto.hu/userfiles/m...panzio_kft.jpg

(red text = rotor bearing oil supply nozzle
Purple text = oil squirter)

The more oil flows through the eccentric shaft, the better it will cool the rotors. Shaft wear is not common, since the bearing’s metal is softer. Balancing the shaft has more importance, but this shaft was found to be good.

New heart

The car received an all-new factory (Japan only) engine, because according to the owner's expectations, it must be able to serve at least another problem-free 100 000 km. It has all the chances too, as oil changes will happen at every 10,000 km at the most, with fully synthetic 0W-30 oil. Shorter oil change intervals and the higher stability of the fully synthetic oil are a great step forward. The lower cold side index motor oil will also assist in faster eccentric shaft lubrication at startup, which will reduce the load on the eccentric shaft bearings. This is further helped by our mazda-auto phase-II modification that was also applied to the new motor.

Application of the mazda-aurto phase-I modification will increase the supplied oil quantity which improves the RENESIS’ load bearing capability. In addition, the careful break-in procedure will now help to prolong the life of the engine. Max. RPM during the first 750 km was up to 3000-3500 then until 1000 km in some cases up to 4000.

http://www.mazda-auto.hu/userfiles/m...rga_istvan.jpg

As a private opinion, I want to note that quite a number of Mazda RX-8s in Hungary began their life as demo or test vehicles, and unfortunately, due to lack of sufficient information and warning, these cars had no chance for the aforementioned gentle break-in. There are some exceptions of course.

Old and new

Warm start problems of the old engine were probably caused by the rear trochoid housing’s wear and damage. The crack likely appeared due to rapid temperature changes that were caused by ignition issues, careless break-in or both. Replacing the trochoid housing and the cost of all seals plus labor of a high quality remanufacturing process is likely getting close to the price of a brand new factory engine.
Moreover, in this case we’d only end up with a remanufactured motor (reusing some less worn - but still worn - parts). So I guess it needs no further explanation that life expectancy of such a remanufactured motor cannot be expected to compare to a new engine.

WARNING! Contrary to other rumors, Mazda uses only completely new engines straight from the factory in Japan. These are not remanufactured engines, which can also be proven by their serial number. Remanufactured engines are only used in North America, but these cannot be imported.

Reads much better, thank you.

Very good read, thanks again man!! It reaffirms some things I believe (more oil pressure, proper warm up, and 0W oil).

Thanks again, I really appreciate it.

I'm curious if the 5W-20 Dexexlia is dino or synthetic? Or did I miss that?

Thx for the translation ! ahh, much better than some "robotic google translate" :)

this part

you can say it's a design defect, or not.

it's still based on a 20-30 freaking years old design, it's the same freaking bearing for all the years + this is the highest power NA engine + it's calling for 5w30 oil ... well at least 5w30 is better than 20? you see marks like that much SOONER on 5w20 engines than 5w30 ... oh yeah 20w50 ALL THE WAY BABY :lol: umm yeah


ohhh and did they mention SYNTHETIC OIL IN ROTARY? OH NO YOU DIDn'T ANGRY MOBS OF YAY U DON'T KNOW SHIT MAZDA KNOWS BETTER WILL GO AFTER U NOW ! :lol:

They comment on the stationary bearings failures as a low pressure problem, but bearings load up with hydrostatic pressure also from turning.

9krpmrx8 didn't have any of this on his teardown, but he did run 0w40 or 5w40 oils.

Many people here know to run at least xw40 oil to preserve those bearings.

I noticed that Subaru warned against using 5w30 in their turbos, and I see better used oil analysis with other oils like 0w30, 0w40, and even 10w30.

Yeah I am pretty set on either 0W-40 or 5W-40 Mobil1 after seeing how well my bearing looked. there are usually oil change specials on either 5W-40 or 0W-40 mobil1 at all times between the different parts stores so I will get either depending which is on special.

The Dexelia is conventional oil. They use 5W-30 as that's the recommended oil in Europe.

What about the point they author(s) bring up against xw40 or xw50 and less flow at the same pressure thereby reducing cooling and providing less oil to the bearings?

I don't run stock oil pressure. 0W is your friend.

Excellent article , thanks for putting the time in to share

Well no but there are many other S1s out there that might think about their point. Seems like it would be a non or minimal issue in an S2 too at least givwn this authors discussion.

I agree, if you are running stock oil pressure is something to consider when you make your choice in oil. For me, I never saw a difference in oil pressure between the dealer fill 5W-20 (mobil clean 2000).0W-30 GC, to Rotella T6 5W-40, Mobil1 5W-40, and Mobil1 0W-40. S2 owners need not worry about oil pressure or the OMP system.

Yep Agree...

I go in this order..

1.Warm Up (Always has been and always will be with any rotary, at least until coolant temp reaches 40c, after roughly 4-5 min's from stone cold)
2.Oil Pressure (Higher pressure more flow/renewal/cooler oil at Bearings.
3.0W, I don't and will never agree in a rotary, 5W30 Minimum*.
4.Pre-mix

* Provided an OP upgrade has been done.

3. Yeah, a 5w30 is the minimum weight to ever run, and 0w40 is slightly thicker at all temps so no oil pressure upgrade needed.

Most people never warm up their cars...Mazda's re-manufactured motors scare me.. mine has held up so far 20k miles of boost @10 psi... once this motor goes i cant wait to see how the internals look. My FC had about 130k miles before it went out due to cracked housing putting combustion in the coolant system, and it didnt look nearly as bad as this!

Hello Tamas,
Many thanks for your translations..............
Best regards from the Netherlands...........
Ruud

Yeah I was down right religious about warming my car up, oil changes, etc. And according to Rob at pineapple the housings in my reman that failed after 30,000 miles should not have ever been reused but Mazda chose to reuse them so..........

In the end a failed coolant was the culprit on my engine but he said the crack in the housing near the spark plug hole would have become and issue sooner or later.

No bearing damage on either our S1 or SII engine with ester synthetic Xw-30 oil, even under race abuse + shock loadings.