Originally Posted By: d00df00d
Originally Posted By: mazdamonky
the oil that is provided by Mazda Japan for the rotary engines is a Group III oil which by their definition is not a synthetic.
Are you talking about Dexelia Ultra or Synthe Renesis? I'm not sure what Dexelia Ultra is made of, but Mazda says Synthe Renesis is PAO/ester.
I am not 100% sure which oil it is. I am just going off of some information I read a while back on the Rx7club or rx8club forums when I was doing my first bit of research on why people think Synthetic is bad for Rotaries. I believe they had a Mazda rotary engine oil similar to current Mazda 0w20. It was house branded but made by someone else obviously. Either way, I do know that there are synthetic oils made specifically for rotaries that are PAO/Ester oils and many have used them and had fine luck. As for Carbon buildup, I have been running Synthetic for the past 20k miles with 5k mile oil changes on my 85 and there is no major carbon buildup (at least no more than beforehand) when viewed from a camera inside of the spark plug hole. Today's synthetics are very different from Synthetics of many years ago.
As for Rotaries and carbon buildup, I don't think the oil really causes any major difference now days. It is more related to people who do short tripping and never get their motors nice and hot to burn off any carbon buildup. My recommendations are to get the engine up to 5-6k rpm and just drive it there for 5 minutes once every couple of weeks or to just take it for a good 30 minute drive on the freeway once a week and hit your redline at least once or twice while the motor is hot.
Originally Posted By: mazdamonky
the oil that is provided by Mazda Japan for the rotary engines is a Group III oil which by their definition is not a synthetic.
Are you talking about Dexelia Ultra or Synthe Renesis? I'm not sure what Dexelia Ultra is made of, but Mazda says Synthe Renesis is PAO/ester.
I am not 100% sure which oil it is. I am just going off of some information I read a while back on the Rx7club or rx8club forums when I was doing my first bit of research on why people think Synthetic is bad for Rotaries. I believe they had a Mazda rotary engine oil similar to current Mazda 0w20. It was house branded but made by someone else obviously. Either way, I do know that there are synthetic oils made specifically for rotaries that are PAO/Ester oils and many have used them and had fine luck. As for Carbon buildup, I have been running Synthetic for the past 20k miles with 5k mile oil changes on my 85 and there is no major carbon buildup (at least no more than beforehand) when viewed from a camera inside of the spark plug hole. Today's synthetics are very different from Synthetics of many years ago.
As for Rotaries and carbon buildup, I don't think the oil really causes any major difference now days. It is more related to people who do short tripping and never get their motors nice and hot to burn off any carbon buildup. My recommendations are to get the engine up to 5-6k rpm and just drive it there for 5 minutes once every couple of weeks or to just take it for a good 30 minute drive on the freeway once a week and hit your redline at least once or twice while the motor is hot.