robrecht

There was no wrath whatsoever in my reponse, but I also could not be sure if it was a serious question. I don't like the hostility that is often directed at noob questions. We all have to start somewhere and sometimes people don't even know enough about a subject to perform a good search and even if they do the discussion found will often be over my head anyway. So I think it's usually best to give a quick or even a generous answer with a link for further reading. There's a certain amount of thread drift in all our lives.

Nubo

You still need oil in the crankcase, to lubricate the moving parts, just like any engine.

In terms of a rotary engine, the engine oil is also used to cool the rotor.

Also, in the RX-8 some engine oil is pumped via an oil-metering-pump (OMP) into the combustion chamber to lubricate the rotor against the housing, and and provide a compression seal. This bit of oil is consumed. But this is not the only way to provide this lubrication. The alternative is to mix a small amount of oil in the gasoline. This delivers lubrication to the walls of the combustion chamber (rotor housing). Either of these methods will work. Some people use the premix to supplement the lubrication that the engine is already getting from the OMP. Others disable the OMP completely and rely strictly on an appropriate concentration of premix. Still others modify the OMP so that it takes oil from a separate resevoir, so that they can use oil more suited to the purpose.

jsjjr

iTrader: (1)

Totally agree. I was mostly basing my comment on the response given to other noobs (as well as myself) when first venturing onto this board and asking questions that are 'new to us'.

nycgps

iTrader: (1)

you should say " ... mix a small amount of 2 stroke PREMIX oil in the gasoline ..."

Cuz there are tons of dumb n00bs out there and when they see your post, they might think "oh just dump some MOTOR oil into the gas tank and thats it ! "

Nubo

Well I was trying to strike a balance between answering the question and re-typing the entire thread :P

rx8t20046sp

sorry for causing problems and being a noob. I have never been to a site like this and still not sure how to properly use it. I appreciate you taking it easy on me and no laughing to hard at my silly question. Like he said we all have to start somewhere. Ok so i went to research Redline and Royal Purple oil..seems that Oreilly here wants 9bucks a quart for 5-20...and since noone sells Redline here in Lincoln..i went to the site and it was 43.00 for a gallon. So if Redline is the best around 50 bucks with shipping sounds good to me. Its so close in price to the RP.

Also you guys that use this oil...do you experience oil loss before your next oil change? If so I should prob get some extra quarts huh? What brand of oil filter do you recommend? Im using Mazda Filters cause i figure ...hell if the manufacture puts them on the car it will be ok till i find a far superior filter.

Ok last question...and dont "noob" me for this...the extended warranty for 100,000 miles....am i correct and saying it covers engine and tranny?? I heard about it but never got a letter or anything telling me what EXACTLY it covers.

Thanks all for your help with any or all of my questions!!

nycgps

iTrader: (1)

Use at least 5 or 10w40. Your engine will thank you for it.

oil lost? I think you're talking about OMP.

this engine, by design(its more like a compromised, but thats for some other thread) will "drip" a tiny bit of oil every rpm to lube the engine internals. so after couple hundred miles you "should" start seeing your motor oil level drop.

when you pull your dip stick out, there is 2 bars there, its about 1.75 quart in between. and its pretty normal to burn about 1 quart of oil every 1000 miles.

Just top it off every 5 fill ups at gas station. you will be fine (until next oil change of course)

For oil filter, you can stick with Mazda, its pretty good quality for the price (around 5 bux, its usually made by Denso), You can also try WiX. Its pretty good too. if you want somewhat better stuff (not like much MUCH better, a tiny bit I would say) you can go for Mobil1(made by champion labs I think) or K&N, both cost about the same, for the same price I would get K&N for the top 1" nut, easy removal.

Stay away from FRAM filters at ALL COST.

Im not sure about 09, but 04-08 modle ALL has 100,000 miles or 8 years engine warranty, whichever comes first.

Powertrain is 60,000 miles or 5 years, whichever comes first. all 04-08.

for bumper to bumper, 04-05 has 50,000 miles or 4 years, whichever comes first. 06-08 has 36,000 or 3 years. whichever comes first.

meskism

+1

rxrocks

hey all,

Just wanted to add my input to this endless thread.

First of all, forget all the "snake oil" additives out there.

For normal street use, including having fun with the car where possible, other than on the race course, any name brand oil is fine. Mazda has to warranty the engine per their recommendations, so the 5W-20 rating works for me.

Now, here's why they don't want you to use a synthetic or semi-synthetic oil in the rotary engine for normal street use. Synthetics don't burn off under high heat as much as conventional oils do. You would think that would make synthetics a "better" choice for those who like to "pamper" their cars for the slight additional expense.

But....in the case of the rotary engine, when equipped with a catalytic converter as the cars for sale to consumers are equipped, the higher flash point of the synthetics, which cause them not to burn off at a certain point, actually harms the cat converter by way of unburned oil fouling up the cat, which decreases performance and creates other problems over time as well. This is probably the major cause of problems with the rotary engine in the RX 8.

Please don't misunderstand where I'm coming from. Synthetics are the best, but not for a cat equipped rotary. However, as mentioned earlier here, any name brand conventional motor oil has more than enough protection to keep your engine happy for a long, long time.

Unfortunately, Mazda does not include the explanation made here in the owner's manual. It just specifically says not to use synthetics.

The rotaries that are raced minus the cats can and should use synthetic oils, as you see on the sponsership ads on the cars.

I await the onslaught and venom to come.

okrx8

Ok, I looked up the flash points for Amsoil and Castrol GTX. Amsoil 5w30 XL = 453 degrees F and Castrol GTX 5w30 = 400 degrees F. Granted the synthetic has a higher flashpoint but the exhaust gas temp of the Renesis is 1600 degrees F (according to Racing Beat). I find it hard to believe there is anything 'unburned' in the cat, I could be wrong but the numbers speak for themselves. I am currently running Amsoil 10w40 and premixing 6oz 2-cycle in the gas tank. I might switch back to conventional oil as this discussion boggles the mind....

RX-8.40

Boggles my mind too...The info that I have taken from the oil disscusions - unburned synthetic oil will actually gum up the rotary engine and leave a film in the engine over time. That is the non technical version ; )

BTW - Have you noticed any difference using the gas/oil additives, I have been considering trying one? Is acceration from 5k-9k any smoother?

okrx8

With the premix i did notice a change in the engine note, it does seem to rev smoother. Now that i have 10w40 synthetic...it seemed to smooth it out even more. I am keeping track of my millage too, first tank after the oil change was the best MPG I have had since i bought the car, I will post my results in a month or so.

swoope

iTrader: (5)

this was debunked in the early pages.. i think in the page 10 to 20..

beers

Nubo

6 years and 845 posts later.....

If there was any real problem with synthetics don't you think someone would have demonstrated that problem by now?

The "synthetic bogeyman" is sort of like extra-terrestrials. All kinds of reports and claims but somehow we never get any conclusive and verifiable evidence.

nycgps

iTrader: (1)

Dude, you dont even know what you're talking about. can you just ... dont say a word ?


if your "full of bull" is actually right, then do you mind to explain why Mazda Japan Sells PAO based "FULL SYNTHETIC" oil for Rotary engines to their customer ?

You know you can't.

Also, you dont even know what's wrong with 5w20.

recommend? well well, my my. Go perform every single service at a Mazda dealer first before you talk about "Mazda recommended"

Just stop posting in this thread.

so long

rxrocks

Your comments and theories about additives, syn. vs. non-syn, premix etc. weight etc. pertaining to street RX 8s are just like the JFK assasination and 9/11 conspiracy believers.

You have problems dealing with Mazda USA recommendations despite the fact that they are responsible for their statements. Why, would they give you anything other than advice which will give your car anything other than maximum life and enjoyment? Where is the all-important monetary gain in not providing the best care for your car? The owner's manual should be your bible, and, disregard those dealer recommendations that tell you to do maintenance in addition to or at more frequent intervals than illustrated in the owner's manual.

No disputing many of your manufacturer's product documentation examples, but...other than outright track racing, they simply don't apply to "stock" RX 8s. Nor do comments about what Japan, Europe, N.Korea, Cuba or the rest of the world uses.

End of story. Those of you who use your own "concoctions" are lucky when Mazda makes good on your botched "abortions" to their engine. They have a pretty good idea what causes engine problems other than their own internal issues, which they at least are upfront about by way of their TSBs.

cajunrx8

Got my popcorn!!! This is gonna be good.

ASH8

Yes, Mazda are aware of the reasons for engine failures, that is why ALL the changes were done to the 09 RX-8's, particularly in regard to "Lubricity"...or Oiling of the middle section of the Apex Seals.

For pre 09 RX-8 owners, the ONLY way to help lubricate this area is to Pre-mix...that is two stroke oil in your gas...there is NO other way.

Will all the changes done to the 09's help to extend engine life?, only time will tell and NO other changes were done Internally to the engine rotors, seals, eccentric shaft or bearings.

It has been my opinion since the release of the RENESIS that the "Grade" of oil recommended in the USA is too light for extreme or hot summer days.
A 5W20 is recommended to try and improve MPG.

A 5W30 or even 10W40 grade of oils are better for any rotary.
What the rest of the world uses.
Earlier RX owners even use 20W50 grade.

The main cause of engine failures are due to bad compressions results after a test.
Why, because of poor sealing of Apex Seal (s) due to premature wear and or High Carbon build up causing Apex Seals or Springs to Jam or Stick which will also produce the same poor compression test results.

swoope

iTrader: (5)

so you are saying synthetic is bad! ?



































but really your post covers it about as best as it can be done.. very nice job again ash..

as to the syn vs dino. i have done both. both work fine. changing it often out weighs what you use..


beers

ASH8

Scott.....

I am not going to step on THAT landmine!!!...

But actually, I stick to all mineral 15W40 in Summer and 5W30 Winter..

Just did my 10K service yesterday actually, I flushed out the oil with a another fill and drain and changed the oil filter.

She runs beautiffully... and yes I still pre-mix even with the 09 changes.
SHOCK...HORROR!!!

Ash

Nubo

What the rest of the world uses is certainly relevant if the engines are mechanically identical. And given the incidence of failure in "5w20 land", that much more so.

The cost/benefit analysis has more parameters. The cost of not meeting Corporate Average Fuel Economy standards is very high, for example.

nycgps

iTrader: (1)

rofl. that simply means you dont know **** about oil and what does it really do, and knows nothing about rotary engine.

if you think the user manual is your "bible" dig it out and READ it. 5w20 is "recommended" not "required". in fact, it has a little table on the next page or so that tells ya all kinds of oil that you can use. plus, if owner's manual is your bible. try to follow all the **** on it before you open your mouth about the "manual = is your bible" thing again.

maximum life and enjoyment? rofl. last I know Mazda is a business. a Business is here to make money. They are here to sell you something that works for "certain" period of time. they're not here to make sure that your purchase will last for the next 20 years.



Ask Mercedes guys how often do they have to ship their cars back to factory for repairs? I know one of my uncle has a S500. it already cost him over 20 K to fix it.

rofl.

so, now the whole world gets the same engine and stuff. the only differences are different oil weight and emission rules (ECU version). and we're the ONLY country that has this engine recall. Hmm. are you smart enough to know WHY is it happening ? oh what god hates us ?

Most of the old timers here "already" knew why Renesis in the USA market failed before Mazda even issued their Engine recall. Worn out apex at the center (lack of omp rate, faulty oil injection design, etc), e-shaft bearing wear down to copper, etc.

Mazda knows they fuxked up, but no one really blamed them except for maybe the way they inject oil, that has been updated on the 09+ model with 3rd injector and new omp.

the rest? blame it on Emission/CAFE rules, your "beloved" 5w20 is part of the cause too.

nycgps

iTrader: (1)

Where is mine? dont be cheap.

Premix should be used on ALL rotary engines. too bad. they have to do the OMP crap or else the car wont sell.

20w50 here baby

Spirograph

I just got an '04 6 speed w/ 36k, so I don't know what oil has been used in it so far, but I'm guessing all 5w-20 since the carfax showed lots of listings from a Mazda dealership. I live in Phoenix so I want to change to something like 10w40 or 15w-40. I know that draining oil only removes part of the oil, so is it okay to drain the 5w-20 and replace the rest with 15w-40? I'm just sticking with dino oil for now until/if I disable the omp to pull from a separate canister.

ASH8

/\ Yes, you can mix any type of engine oils..

A 10 or 15W40 Dino would be fine for high temp locations..it is what I use.

You can if you want drain your existing oil, fill with the new 15W40 and run till engine is hot, and drain again, this gives a good "Flush Out" of old oil that won't drain from oil coolers and all the plumbing (hoses).

Then refill (change oil filter) with fresh 15W40.

You will require two containers of new oil to do this procedure though.