morganrogers

Gotta say - I was confused by that ...

Here is a car that with no marketing yet has sold over 1000 units , has the best reviews I have ever seen (collectively I mean - to my knowledge there is only one mag that has dis'd the RX8)
... and more importantly has £1000 of my money !

What coffin ?

morganrogers

Actually - scratch that - I dont really care !

I am itching with antici.........pation for this car - and that is all that matters !

rael

Thanks jimbobjoe.

I think I am in the silent majority, who considering the aggresive tone of this specific thread have not posted, that rarely or never check oil. My XJS used to be serviced every 6 months and the TTC is 18 months old and coming up to its first service with 1 oil top up needed up when the low light came on.

I think it is unusual to check oil every 2 week in todays modern cars, even if the manual suggest that as best practice (its very easy to put that clause in as a warranty get-out). If I have to do that for the 8 because the rotary calls for it then fine but let us not pretend that we would have to do this for every new car, it is not the case and I imagine the majority of readers don't do it that regularly at present.

rael

morganrogers

...Perhaps it is a conspiracy to get us to buy the gas-bonnet-struts from the expensive extras catalogue.....

Make 'em open the bonnet often enough , they will buy the struts ! MWUH-ha-haaaaa ! (evil laugh)

garygfx

Thanks to those who were brave enough to speak out and confirm they don't often check oil levels or hardly ever need to put a drop into their piston engines. Let's face it, piston engines are pretty refined beasts these days. Hang on, hang on! Let me finish!

I've just had a thought which has put this whole issue into perspective for me. It will be obvious to you but so far no one has touched on it in this thread. Piston engines have had well over 100 years of development history multiplied by the number of individuals and companies that have had a part to play in inventing more effective theories, components and subsystems.

In contrast it seems the rotary engine, while on paper is as old as the piston engine, has taken a back seat when it comes to mass development. Apart from Mazda what percentage of manufacturers have invested and produced rotaries for 40+ years? With that in mind it should be no surprise that the Renesis doesn't have all of the refinements and benefits of 1000+ company years of development. I'm sure Madza will eventually address oil consuption issues just as it has been resolved by piston manufacturers. Same goes for fuel consumption. There's bound to be an "FSI" equivilent development for rotaries somewhere down its evolutionary path. To be fair, considering the fraction of development that rotaries have had next to pistons, the Renesis is pretty impressive.

morganrogers

I think RENESIS is pretty impressive on its own - i.e. without such considerations...

But then I am in the minority who are buying this car because of the wonderful engine !

The Ace

Seems to me like, in order to reply to the posts quoting me, I have to YET ONCE MORE repeat what I have said from the word "GO":

1) Rotaries burn oil. They dont burn it just for fun, or because their gaskets are leaking. They burn it because the OMP injects it into the engine to keep the seals lubricated. So, oil level IS GOING to decrease. You may rest on the functionality of the "Low Oil" light, but oil WILL burn, and its level WILL decrease.

2) You may as well never have to top up. If you dont drive it like a maniac, the frequent oil changes will cover for the fact that rotaries burn oil. So, you might end up not having to top up ever. On the other hand, its nice to know what your car is doing.

3) To whoever doesnt check the oil level: sorry, but you dont deserve to have a RX8. If your Vauxhaul, BMW, Opel, VW, and whatever else didnt need a single top up, then good for you and your car. HOWEVER, the RX8 and the rotary are different. You dont actually expect to pop a DVD into a VHS player, and expect it to play, do you ? Operate and treat each machine as it should be operated and treated....

4) A seperate oil tank just for the OMP has been considered for all RX7s, but the system would be much more complicated, and the chances of someone even accidentally forgeting to top up the second reservoir would lead to more engine failures. Thats why the OMP gets the oil from the same place (oil pump, oil pan).

5) As for the "Low Oil" warning light, I have to admit that I was wrong. After checking the FSM, section T (15), the warning light is connected to a floater in the left side of the oil pan. While the gauge is ofcourse connected to the pressure sender right before the filter. Just to let you all guys know......

PS: As for the "my RX8 stopped working because I didnt top up the oil like I was supposed to" remark, well a) the person who says that must be shot on sight, and b) we can safely assume that this is the same person that gets stranded because he forgot to put in gas Lets not deal with these types any more, shall we ?

RobDickinson

I think at one point in the 90's mazdas rotary development team was down to 2 people.


Rotaries have gotten benifit from modern tech, piston development/materials science, engineering,production and such, but development on the actual engine has beed a very small fraction of whats gone into piston engines.

Cerrtainly years behind where it should be - people say they burn oil, have emmisions/reliability problems etc.

In piston tearms I'd say ther still somewhere in the 70's or so, astonishing the Renasis is so good tho isnt it ?

ChrisW

Didn't Mazda claim somewhere that the RX-8 would only consume 1 litre of oil per 10,000 miles (or maybe it was kilometres)?

The reason given was that as the Renesis has no peripheral ports then the oil on the surface of the rotor housing was not continually being swept out of the exhaust ports by the apex seals.

The Ace

Dont know about that, but 1lt/10000km sounds a bit stretched....I know that the Renesis is more advanced than the 13REW, but in order to go from about 0,5lt/1000km (normal consumption for 13BT and 13REW) to 1lt/10000km, the consumption would have to become 1/5.....could be done, but I would rather guess about 2lt/10000km to be more safe

garygfx

Someone mentioned oil changes. How often do Mazda advise oil changes and using an average priced oil how much would it cost roughly please? I'm asking so I can get an idea of the maintenance costs. My dealer can't say what the servicing costs are yet so I thought I'd start with oil change costs.

Thanks.

RobDickinson

We dont know what oil is recomended yet - it probably wont be the same type as in the US.


US schedule says 5000/7500 mile servicing, but UK will probably be 12500 mile(?).

Japans was shorter again I think, but their mad.

morganrogers

M...MM....M...MM....M.....Mad sir !

The Ace

Again, I dont know what Mazda is "recommending" for the RX8, but I can tell you for sure that the RX7s responded much nicer when you had complete oil changes every 5K km Since you will be using a dino oil of a 10-40W, it will be rather cheap, so it wont cost you that much (cheaper than having to change fully synthetic 5-40W oil in a M3 or a VTEC engine)

AndyPearce

I'm sure many won't be surprised to see me come down on the side of those who think this is a negative for the RX8 - I've said before that I'm possibly buying one despite the rotary engine!

I drive a car that is almost as quick as the RX8 (is quicker top end) and I rarely have to top up the oil between services (10k.) It's not something I'm used to doing, I'm almost always in my suit when I'm filling up (which will be every 2 days in the 8 probably) so it won't be something which I can just fit in. I won't be washing it every week (hence Titanium!) and so that's another natural time to check it that I'm missing.

That's not to say I won't take time to do it on the RX8 but it's not something I'm likely to do religiously, so it does concern me that I can be affecting the life of the engine.

Ace - I think that you have an eliteist attitude when you say people like me don't deserve to own an RX8 - at then end of the day it could have 10,000 hamsters under the bonnet and I wouldn't care as long as I only have to worry about how I drive the car. I think you have a misguided bias towards the rotary engine and while it may have allowed the RX8 to have been concieved, I would have been just as happy (if not more so) if they had put a piston engine in it.

mr_digital_uk

Andy,

As my Mazda Xedos has aged (80,000 miles) I have had to take a little more care on the oil, but it isn't that much of a drudge.

Like you, I'm on the road most days and always in a suit.

Popping the bonnet every couple of weeks, checking the oil and buying a litre once a month (if that) cos I dropped below the minimum mark doesn't really cause an issue.

Most garages have paper towels, gloves etc if you need them.

Adds about two minutes max to a stop.

BTW ... refer to my previous post and you'll see that I was being daft and buying more expensive oil that needed replacing more often. Definitely need to go with what Mazda recommend.

zoom44

a "complete" oil change would require draining the entire system including what is in the oil coolers and what is in the cooling channels of the block. not only would this be dificult and time comsuming to do getting the airin the lines lines and oil coolers bled out would be a right pain. during a normal oil and filter change at 5000 or 7500 as is recommended in the US manual will only change out between 3.75-4 quarts of the 7+quarts in the system. also the recommended oil in the JDM, Canadian and U.S. manuals is not 10w-40 but rather 5w-20.

zoom44

actually with this oil level light and sensor it comes on before you are a quart low, not counting the ones in the sumps with the wrong baffling. so waiting until the lights comes on is not terribly bad as long as you took care of it soon after it comes on.

and on the oil consumption: i watched the level thru the first few fill ups and it didn't drop much at all. i then lengthened period between checks and didn't add any until the light came on at @2800 miles at which point i added almost a quart. if someone wants to do the conversions it might be helpful to the rest of you. i'd do the conversion myself but being a lazy american..... :p

AnilS

This all adds up to the fun and the pleasure we will receive for picking this wonderful car.

I know when I get mine (without the bonnet dampers as they'll need replacing from continual use), the renisis engine cover will remain in my garage.

One final thought (and maybe RX7 owners could help). With oil being burnt and sent out of the exhaust, how long before you have to replace the catalyst in the exhausts ?

AnilS.

Jon H

I know its probably been said on a few threads already but I think it needs emphasis - DO NOT use synthetic oil (eg Mobil 1). The engine is designed so that oil is applied constantly to the rotor tips and needs to burn away naturally. Synth doesnt burn away cleanly. So its OK to use cheaper oil (not ***** though, best to use the same oil that comes in a little fun pack in the boot or a similar grade, non-synth by a big name, eg Castrol, Shell).

And, you guys in USA, what is a quart? Pardon my stupidity but I aint got a clue what one of those is, even though use limeys probably invented it a few centuries ago.

zoom44

1 quart [US, liquid] = 0.946353 liter from http://www.onlineconversion.com/

garygfx

So, a US gallon is almost a UK gallon, a quart is nearly a litre, and a ps is just a bit more than a horsepower. All of these measurements are so close to each other but someone had to make up another scale! I've learnt a lot this week by joining this forum!

Zoom44, thanks for the real-life info on oil top ups. If your car is the norm then that's just 2 quarts/litres a year for me! Not as bad as I thought.

AnilS, that's an interesting question about replacing the cat. Hopefully someone will tell us it's every 20,000 miles or more! They're not exactly cheap are they?

Jon H, no synth oil. Gotcha. I wonder if someone can invent a formular that doesn't burn away so much. Perhaps increasing its resistance to heat somehow. A special rotary oil.

zoom44

no problem. i should also have mentioned that the distance between the "full" line and the "add" line is @1.75 of those US quarts. so according to the stick i still could have not added any for awhile but i wanted the light to go away. and there has been some mention that if you let the light go for too long(i don't know how long is "too long") that the engine will go into a sort of "limp home" mode not allowing you to go WOT or rev above a certain lower limit until you correct the situation. so all of these things have been put in place with the avg joe in mind, so that it is harder for him to hurt the car from inattention. i think most will be able to handle it.

again i wonder if you're in your suit on a rainy day or whatever isnt their someone at the petrol station that could do the adding for you when the light came on? buy them a pint or something and i'm sure they would be more than happy to do it if it is an inconvenient time for you.

eccles

The difference between the US and Imperial gallon is primarily due to the fact that a US pint is only 16 fl.oz. instead of the 20 fl.oz. of an imperial pint. The fluid ounce is also ever so slightly different, resulting in the US gallon being approximately 4/5 of the imperial (0.83 actually). What the rest of the world calls a 44-gallon drum is a 55-gallon drum over here.

Murphy

When it comes to conversions, google is your friend!

Go to the normal google.com seaarch prompt and type in

12 km per litre in miles per gallon

Clever! :D