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Rotary engines

How often should you do a full oil change with a rotary engine?

Is this a Mazda?

You could phone a Mazda Dealer as they made/make them, but from what I could find on a short net search, they say to follow the manufacturers recommendations as written in the owners manual and doesn’t mention how long between changes, only to keep an eye on the oil dipstick level.

Apparently these engines can use up to a quart of oil in 1000 miles to 3000 miles.

I don’t know of any special specs for them. Perhaps one of the techs would know.

Did you just buy the car? if yes what did the previous owner use as a schedule (you did ask didn’t you?) or if you are not a new owner what schedule have you been using?

What is the current level of oil consumption?

Lastly why do you specify “full oil change”? is there any other type?

Check the owner’s manual. As I recall I changed the oil on my RX-7 about every 3-6,000 miles. It is not a car you want to depart from the recommended oil maintenance however.

“A full oil change?” As opposed to what, a partial oil change?

In my opinion, the oil in a rotary engine should be changed every 3,000 miles. Same goes for the oil filter. This is much more often than I suggest for conventional piston engines, but the Mazda rotary is not a conventional piston engine.

You also need to check the oil level on a regular basis, because a rotary engine will burn some oil as part of its normal operation.

Overheating is death to a rotary. If you should ever suspect the engine is starting to overheat, even just a little bit, pull over and shut it off.

I’m not sure about the RX-8, but the RX-7’s had a little oil injection pump that injected a small amount of engine oil into the intake ports to lube the rotor tip seals…Many savvy owners modified this system and fed the pump with TC-W outboard oil which is much better suited for this purpose. This mod also stops the “oil burning” Mazda Rotary’s are famous for…The flow from this pump was regulated by throttle position via a cable linkage…

If this is an RX-8, you should change the old every 3000 miles religiously, don’t let it slip. If it sits over the winter, once every couple days (a weeks at most, go out and start it up, let it reach operating temp and shut it down. Change the oil before you store it and when you pull it out. Check the oil (and coolant level) ever other tank of gas.
If it is any generation of RX-7, all the same apply plus on a Turbo II or 3rd Gen, let the car idle a bit before shutting it off, 20 seconds is usually enough and it takes me that long to collect my assorted things before I get out anyway. You might also want to change more frequently, say 2000, if you live somewhere with widely varied weather (I live in Kansas, it’s a must here).
And the cardinal rule:
Never use synthetic oil, ever ever ever. check your oil often, the motor by design will use up oil. check your coolant too, these motors get hot and will die if they over heat