GC 0W-30/ 1500 miles/Mazda RX-8
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Frequent oil changes are a must on a rotary. Too bad too much old oil stays in the engine and that it dumps fuel into the oil. Cost is the only reason to stray from synthetic.
The real question is, what is shedding the iron?
Try Mobil1 10w30 or 10w40 in the "high mileage" label.
The real question is, what is shedding the iron?
Try Mobil1 10w30 or 10w40 in the "high mileage" label.
Well, not much oil stay in as usual as I am running a single fluidyne oil cooler versus the two factory coolers. I am concerned about the iron as well.
Also, I actually was told that idling to warm up diluted the fuel so I stopped idling my car to full warm during this OCI and now the fuel dilution is worse so I don't know what to think. This motor has about 8,000 miles on it and I usually don't even make it to 3,000 miles between oil changes.
Also, I actually was told that idling to warm up diluted the fuel so I stopped idling my car to full warm during this OCI and now the fuel dilution is worse so I don't know what to think. This motor has about 8,000 miles on it and I usually don't even make it to 3,000 miles between oil changes.
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After it's warmed up daily.... are you flooring the [censored] out of it? If not, you should. 4/5 friends of mine are rotorheads and they have zero issues and they live by exactly this method of maintenance. They have everything from a 79 rx7 to an 09 rx8... drive it hard and it lasts- don't, and they die. That's why so many automatic rx8 cars died, the ecu didn't let it rev high enough (and I have a friend with an auto rx8 that just got his free engine). He's now premixing once a month.
Wouldn't Redline be good for this application? Very shear stable, esters stick to steel and simulate a higher visc oil film, and esters are good at resisting fuel dilution. Do you have any issues that Redline can't handle?
There's more to this application than just the stress. Whatever oil remains in the combustion chamber after the leading rotor tip wipes it away HAS to be burned quickly and cleanly, otherwise deposits will form.
I can't say Red Line would perform poorly in that respect, but just wanted to point it out.
I can't say Red Line would perform poorly in that respect, but just wanted to point it out.
Revving it is not and issue but yes it gets driven fairly hard and this new motor has not been tracked yet but it will be soon enough 
The revving issue among RX-8 owners is a lot of [censored] spewed about forums but that is for another discussion.
The revving issue among RX-8 owners is a lot of [censored] spewed about forums but that is for another discussion.
i use to have a 3rd gen rx-7.these are my thoughts.
stick to a grp 3 oil!,...that is not partly mixed with PAO or esters.
the oil being injected in the engine must burn and it's better if it does so cleanly in order for you to achieve maximum reliability and avoid failure.
ignore racing teams recommendations unless your engine is built exactly the same way.many of these teams use special carbon apex seals(about $3000 just for the seals,last time i checked)and other mods.ignore companies that tell you to use synthetics unless they can assure you they use nothing but grp 3 as base oil.it doesn't matter who swears all up and down,left and right,unless mazda is telling you there has been redesigns that allow you to use ANY type of synthetics,stick to grp 3 oils. it doesn't matter if you or someone else is using PAO/ester and is not having problems......yet.
you are doing 3k OCI.what do you care anyway?take advantage of this and save money. it took me a long time to get used to this because i am a true believer in synthetics of high quality.
the second thing that most people ignore,besides the proper oil choice,is carbon build-up.piston engines must also deal with this but on rotaries,the relationship is a little different.believe it or not,i little carbon build-up actually helps with compression,maximum HP and fuel efficiency.the problem is that too much carbon build-up,can mess up the apex seals. on the newer rotaries there has been yet another redesign to the apex seals which lessens this want/need.
the third thing some people ignore,is the proper A/F ratio or mix.it's not that rotaries are weak,it's just that rotaries with there apex seals are a bit more sensitive to detonation. what's the first thing that kid-racer across the street does when he buys any performance car?....usually,it's an after-market exhaust. on the 3rd gen cars,imediately,the turbo boost goes up(same thing happens when you add high octane,like 103)and bounces off until the computer/sensors bring the boost back down and the timing. you need a controller if you want to add more boost and in conjuction to up-graded injectors.the stock 3rd gen injecters where made to handle about 16lbs boost,no more.
the problem is that after bouncing off a few times nothing may have happended....OR,possibly catastrophic failure.
the forth thing ignored is the side seals.oil temperature is critical to these.imo,an oil cooler is mandatory,even if your just sitting in traffic.i forget what the max temperature was for long life of the side seals.i think it was 230F.
don't worry about a bit of normal fuel dilution,unless you have too much or a known problem and if you do,take care of it.
you have already taken care of most of these things,i think,and are probably aware of most of them so please don't feel insulted if i post all this.
here was my routine with my 3rd gen rx-7 with a stage 1(complete dedicated,to specific max 14lbs boost,computer,..boost controller,..complete full exhaust,no cats,three silencers,including downtube,..intake tube with huge filter,no box,properly separated for cool air only).i would walk into what ever auto parts store and buy the best quality grp 3 oil i could find and OCI at 3k miles with filter. i would alternate between shell v-power and chevron techron so as not to allow too much carbon build-up(including from the two carbon deposit cleaners themselves)and once every two years or 20k miles,i would use seafoam at 1/4 the amount seafoam tells you in the fuel tank and oil,run for a few days,right before i was doing a OCI. i would also dump about 4 oz of 2-cycle mix into every full tank fill-up.
oh,and i used 10w-30 even in florida.i just lived with the fact that this was the best oil for this engine.
i never had a problem,..stone cold reliable.
by the way,i dusted a heck of alot of cars with it,including the latest mustang GT and the brand new(for back then)400HP corvettes(automatics even more so) even though my rx-7 was much older.
..but i don't really care about being a boy-racer too much any more.
i hope this helps and changes your mind about your oil choice,.....you definately don't need PAO/ester in this application.some PAO/ester oils are really tough with high FP and low volatility and will resist burning off more so.great in other cars but not rotaries.sometimes an up-grade is actually a down-grade on reliability. the specialized mazda rotary oils are more than likely just grp 3 with more specific additive tuned for them,...over priced if you ask me.
stick to a grp 3 oil!,...that is not partly mixed with PAO or esters.
the oil being injected in the engine must burn and it's better if it does so cleanly in order for you to achieve maximum reliability and avoid failure.
ignore racing teams recommendations unless your engine is built exactly the same way.many of these teams use special carbon apex seals(about $3000 just for the seals,last time i checked)and other mods.ignore companies that tell you to use synthetics unless they can assure you they use nothing but grp 3 as base oil.it doesn't matter who swears all up and down,left and right,unless mazda is telling you there has been redesigns that allow you to use ANY type of synthetics,stick to grp 3 oils. it doesn't matter if you or someone else is using PAO/ester and is not having problems......yet.
you are doing 3k OCI.what do you care anyway?take advantage of this and save money. it took me a long time to get used to this because i am a true believer in synthetics of high quality.
the second thing that most people ignore,besides the proper oil choice,is carbon build-up.piston engines must also deal with this but on rotaries,the relationship is a little different.believe it or not,i little carbon build-up actually helps with compression,maximum HP and fuel efficiency.the problem is that too much carbon build-up,can mess up the apex seals. on the newer rotaries there has been yet another redesign to the apex seals which lessens this want/need.
the third thing some people ignore,is the proper A/F ratio or mix.it's not that rotaries are weak,it's just that rotaries with there apex seals are a bit more sensitive to detonation. what's the first thing that kid-racer across the street does when he buys any performance car?....usually,it's an after-market exhaust. on the 3rd gen cars,imediately,the turbo boost goes up(same thing happens when you add high octane,like 103)and bounces off until the computer/sensors bring the boost back down and the timing. you need a controller if you want to add more boost and in conjuction to up-graded injectors.the stock 3rd gen injecters where made to handle about 16lbs boost,no more.
the problem is that after bouncing off a few times nothing may have happended....OR,possibly catastrophic failure.
the forth thing ignored is the side seals.oil temperature is critical to these.imo,an oil cooler is mandatory,even if your just sitting in traffic.i forget what the max temperature was for long life of the side seals.i think it was 230F.
don't worry about a bit of normal fuel dilution,unless you have too much or a known problem and if you do,take care of it.
you have already taken care of most of these things,i think,and are probably aware of most of them so please don't feel insulted if i post all this.
here was my routine with my 3rd gen rx-7 with a stage 1(complete dedicated,to specific max 14lbs boost,computer,..boost controller,..complete full exhaust,no cats,three silencers,including downtube,..intake tube with huge filter,no box,properly separated for cool air only).i would walk into what ever auto parts store and buy the best quality grp 3 oil i could find and OCI at 3k miles with filter. i would alternate between shell v-power and chevron techron so as not to allow too much carbon build-up(including from the two carbon deposit cleaners themselves)and once every two years or 20k miles,i would use seafoam at 1/4 the amount seafoam tells you in the fuel tank and oil,run for a few days,right before i was doing a OCI. i would also dump about 4 oz of 2-cycle mix into every full tank fill-up.
oh,and i used 10w-30 even in florida.i just lived with the fact that this was the best oil for this engine.
i never had a problem,..stone cold reliable.
by the way,i dusted a heck of alot of cars with it,including the latest mustang GT and the brand new(for back then)400HP corvettes(automatics even more so) even though my rx-7 was much older.
..but i don't really care about being a boy-racer too much any more.
i hope this helps and changes your mind about your oil choice,.....you definately don't need PAO/ester in this application.some PAO/ester oils are really tough with high FP and low volatility and will resist burning off more so.great in other cars but not rotaries.sometimes an up-grade is actually a down-grade on reliability. the specialized mazda rotary oils are more than likely just grp 3 with more specific additive tuned for them,...over priced if you ask me.
Thanks for the post. Carbon Apex seals? Did you mean ceramic?
I run a SOHN adapter so I am using synthetic only in the motor, the Mobil1 0W-40 is not being injected into the combustion chamber. I also premix the gas as well with Lucas UCL. Carbon is a huge issue in the failures of the Renesis' (definitively not the only issue) which is why I only run Shell 93, no substitutions, and I only fill-up, I don't put $10.00 worth of gas here or there, etc. So with each tank of gas it gets a full dose of premix. I also run a can of BG fuel cleaner through a tank with no premix every couple of months.
I run a SOHN adapter so I am using synthetic only in the motor, the Mobil1 0W-40 is not being injected into the combustion chamber. I also premix the gas as well with Lucas UCL. Carbon is a huge issue in the failures of the Renesis' (definitively not the only issue) which is why I only run Shell 93, no substitutions, and I only fill-up, I don't put $10.00 worth of gas here or there, etc. So with each tank of gas it gets a full dose of premix. I also run a can of BG fuel cleaner through a tank with no premix every couple of months.
yeah,could have been ceramic.my rotary kick ended a long time ago.
your adaptor sounds interesting.i never used that.
remind me again,the amount of oil that lubricates the side seals,once it's done lubricating,where does it go?
by the way,i have personally met owners of 1st gen rx-7s with very high mileage.i remember one of them had 214k with an original,never rebuilt engine.he was extremely proud of it but was a stickler for maintenace,like keeping all coolant hoses like new condition.
i also find it funny how people talk about the simplicity of the rotary engine.that may have been true about the originals but the later ones had an extreme assortment of secondary gadgets and more hoses with plastic one-way-valves than you could easily count.this is especially true on the twin-turbo.a big part of what people would want to charge for a re-build was replacing these.cost about the same as rebuilding a bmw engine.
your adaptor sounds interesting.i never used that.
remind me again,the amount of oil that lubricates the side seals,once it's done lubricating,where does it go?
by the way,i have personally met owners of 1st gen rx-7s with very high mileage.i remember one of them had 214k with an original,never rebuilt engine.he was extremely proud of it but was a stickler for maintenace,like keeping all coolant hoses like new condition.
i also find it funny how people talk about the simplicity of the rotary engine.that may have been true about the originals but the later ones had an extreme assortment of secondary gadgets and more hoses with plastic one-way-valves than you could easily count.this is especially true on the twin-turbo.a big part of what people would want to charge for a re-build was replacing these.cost about the same as rebuilding a bmw engine.
The adapter is actually made by an aviation company for use of the Renesis engine in airplanes. It's pretty cool, just mounts between the factory OMP and the block and pulls clean 2 stroke (premix)from a reservoir.
In the stock setup the OMP (oil metering pump)pulls used engine oil and injects it into the combustion chamber and then it is discharged (not burnt cleanly because its not designed too)through the exhaust ports. The problem is engine oil is dirty and not designed to burn ash less like 2 stroke and the Renesis is lacking a third oil injector like the FD engine and others. Mazda has added back the third oil injector to the second gen Renesis and made other notable improvements as well.
I am anal out maintenance and this being my third engine I feel I have a hold of the problems with this engine so we will see how it last this go round but unfortunately the first gen Renesis is faulted form a design point and it is not something that can be modified or fixed so premixing clean 2 stroke and premixing the gas is the best we can do and hope it works.
In the stock setup the OMP (oil metering pump)pulls used engine oil and injects it into the combustion chamber and then it is discharged (not burnt cleanly because its not designed too)through the exhaust ports. The problem is engine oil is dirty and not designed to burn ash less like 2 stroke and the Renesis is lacking a third oil injector like the FD engine and others. Mazda has added back the third oil injector to the second gen Renesis and made other notable improvements as well.
I am anal out maintenance and this being my third engine I feel I have a hold of the problems with this engine so we will see how it last this go round but unfortunately the first gen Renesis is faulted form a design point and it is not something that can be modified or fixed so premixing clean 2 stroke and premixing the gas is the best we can do and hope it works.
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09+ Renesis motors have a 3rd electronic injector
If you're injecting 2 stroke there is no need to premix the gas.
you would either:
-group 3 all day
-sohn with 2 stroke and your synthetic engine oil of choice
-group 3 and premix
If you're injecting 2 stroke there is no need to premix the gas.
you would either:
-group 3 all day
-sohn with 2 stroke and your synthetic engine oil of choice
-group 3 and premix
Well M1 0W40 shears badly as well but I like the base stocks used and the additive package. I mean it stands up to many 500+ HP engines in AMG's just fine.
Redline 5W30would be worth a try PM if interested..
My third choice would be Amsoil Series 3000 HD 5W30.
If you wanted to try a 5W40 I woul start with Rotella T Synthetic T6 Formula for$20 a gallon at Walmart. Based on UOA I would go from their. RTS used to shear a lot too but UOA where always great. The T6 formula change is supposed to be more shear resistant!It is a GIII but it is darn good oil in spite of that fact!
Redline 5W30would be worth a try PM if interested..
My third choice would be Amsoil Series 3000 HD 5W30.
If you wanted to try a 5W40 I woul start with Rotella T Synthetic T6 Formula for$20 a gallon at Walmart. Based on UOA I would go from their. RTS used to shear a lot too but UOA where always great. The T6 formula change is supposed to be more shear resistant!It is a GIII but it is darn good oil in spite of that fact!
I wanted to add that if I owned anything that was sqirting dirty crank case oil into the cylinders I would have to try to clean up the oil. I would seriously have a look at bypass filtration. Trasko makes a system that simply spin on in place of the normal filter that has a full flow screen for good flow and then use's a special paper roll that looks like toilet paper but is significantly different then over the counter toilet paper.
Their are other systmes as well though besides trasko that have more capacity but require some plumbing. Puradyn makes in my opinion the best bypass filtration units on the market that can easily be configured for any application and have a long long life cycle. Paper towel and cheap toilet paper designs make you change the element every 3000 miles which is messy and a pain in the rear. The Puradyn has a heating element to burn off water, it chemically treats the oil keep the TBN high and the TAN low and it filter to sub micron levels. If I did not already have a Trasko sitting in my pole barn left over from my DOdge I would buy a Puradyn it makes the old AMsoil style bypass look like something a kid would play with like a toy same thing for the cheap toilet paper and paper towel models. Far better to inject clean oil then dirty oil!
Their are other systmes as well though besides trasko that have more capacity but require some plumbing. Puradyn makes in my opinion the best bypass filtration units on the market that can easily be configured for any application and have a long long life cycle. Paper towel and cheap toilet paper designs make you change the element every 3000 miles which is messy and a pain in the rear. The Puradyn has a heating element to burn off water, it chemically treats the oil keep the TBN high and the TAN low and it filter to sub micron levels. If I did not already have a Trasko sitting in my pole barn left over from my DOdge I would buy a Puradyn it makes the old AMsoil style bypass look like something a kid would play with like a toy same thing for the cheap toilet paper and paper towel models. Far better to inject clean oil then dirty oil!
The oil injection algorithm, for emissions, runs it so lean that its definitely worth adding a little lube to the fuel. Engine runs pig rich for the same reason. Only way to get around that is a dyno tune. Anyone thoroughly crack the Mazda ECU yet?
The HM M1 oils might give you a better additive package only with slightly more visc to deal with the dilution and shearing.
The 5w40 HDEO's are definitely worth a try. 0w oils might shear too much too quickly.
Even with a single cooler, plenty of oil in that cooler(unless you drain it) and in the rotors.
My rotaries always ran perfectly regardless of the oil type. 100k+ one 1 with Mobil1. 100k+ on another with Redline. No carbon issues at all because mine were maintained and got timely doses of FI cleaners. And, I enjoy the revs so driving style was a little more fun then with other cars. All the group III vs mineral vs. Group 4/5 is bull.
A little shutdown secret is to rev the engine prior to killing the ignition, to 'dry' the engine. Prevents the dreaded cold start short trip restart flooding issue so common with newbie owners.
The HM M1 oils might give you a better additive package only with slightly more visc to deal with the dilution and shearing.
The 5w40 HDEO's are definitely worth a try. 0w oils might shear too much too quickly.
Even with a single cooler, plenty of oil in that cooler(unless you drain it) and in the rotors.
My rotaries always ran perfectly regardless of the oil type. 100k+ one 1 with Mobil1. 100k+ on another with Redline. No carbon issues at all because mine were maintained and got timely doses of FI cleaners. And, I enjoy the revs so driving style was a little more fun then with other cars. All the group III vs mineral vs. Group 4/5 is bull.
A little shutdown secret is to rev the engine prior to killing the ignition, to 'dry' the engine. Prevents the dreaded cold start short trip restart flooding issue so common with newbie owners.
Originally Posted By: brandini
09+ Renesis motors have a 3rd electronic injector
If you're injecting 2 stroke there is no need to premix the gas.
you would either:
-group 3 all day
-sohn with 2 stroke and your synthetic engine oil of choice
-group 3 and premix
Actually you are wrong. The whole point of premixing the gas is to address the lack of a third oil injector. The center of the apex seal is not getting lubricated so premixing the gas helps with this but doe not equal what a third injector spraying that area would.
09+ Renesis motors have a 3rd electronic injector
If you're injecting 2 stroke there is no need to premix the gas.
you would either:
-group 3 all day
-sohn with 2 stroke and your synthetic engine oil of choice
-group 3 and premix
Actually you are wrong. The whole point of premixing the gas is to address the lack of a third oil injector. The center of the apex seal is not getting lubricated so premixing the gas helps with this but doe not equal what a third injector spraying that area would.
Originally Posted By: JohnBrowning
I wanted to add that if I owned anything that was sqirting dirty crank case oil into the cylinders I would have to try to clean up the oil. I would seriously have a look at bypass filtration. Trasko makes a system that simply spin on in place of the normal filter that has a full flow screen for good flow and then use's a special paper roll that looks like toilet paper but is significantly different then over the counter toilet paper.
Their are other systmes as well though besides trasko that have more capacity but require some plumbing. Puradyn makes in my opinion the best bypass filtration units on the market that can easily be configured for any application and have a long long life cycle. Paper towel and cheap toilet paper designs make you change the element every 3000 miles which is messy and a pain in the rear. The Puradyn has a heating element to burn off water, it chemically treats the oil keep the TBN high and the TAN low and it filter to sub micron levels. If I did not already have a Trasko sitting in my pole barn left over from my DOdge I would buy a Puradyn it makes the old AMsoil style bypass look like something a kid would play with like a toy same thing for the cheap toilet paper and paper towel models. Far better to inject clean oil then dirty oil!
Thanks for the info, I will look into this. This is why frequent oil changes are a must for us.
I wanted to add that if I owned anything that was sqirting dirty crank case oil into the cylinders I would have to try to clean up the oil. I would seriously have a look at bypass filtration. Trasko makes a system that simply spin on in place of the normal filter that has a full flow screen for good flow and then use's a special paper roll that looks like toilet paper but is significantly different then over the counter toilet paper.
Their are other systmes as well though besides trasko that have more capacity but require some plumbing. Puradyn makes in my opinion the best bypass filtration units on the market that can easily be configured for any application and have a long long life cycle. Paper towel and cheap toilet paper designs make you change the element every 3000 miles which is messy and a pain in the rear. The Puradyn has a heating element to burn off water, it chemically treats the oil keep the TBN high and the TAN low and it filter to sub micron levels. If I did not already have a Trasko sitting in my pole barn left over from my DOdge I would buy a Puradyn it makes the old AMsoil style bypass look like something a kid would play with like a toy same thing for the cheap toilet paper and paper towel models. Far better to inject clean oil then dirty oil!
Thanks for the info, I will look into this. This is why frequent oil changes are a must for us.
How on earth does this work? I was under the impression that the rotary engines metered oil into the intake which lubricated the engine... How do you do a UOA when the oil is burnt and sent out the exhaust?
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