Renesis engine issues finally identified?
#101
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Oh never mind. He said "heard of and ripped down." For some reason I read is as if he actually did it. Nevermind. Back to our regularly scheduled program.
#102
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https://www.rx8club.com/attachment.p...8&d=1177052702
from this thread
https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/hold-pre_mixing_surprise-find-108224/
and this thread
https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/interest-fix-fuel-starvation-issues-105156/page8/
from this thread
https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/hold-pre_mixing_surprise-find-108224/
and this thread
https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/interest-fix-fuel-starvation-issues-105156/page8/
For example one said he was using:
Techron every 5K plus the Lucus top cylinder lube/cleaner has a low concentration of cleaner in it. I run 50% Lucus and 50% Maxima 2 full synthetic or quicksilver full synthetic
Hell they might as well been using MMO.
If you put crap in your gas tank, your car will break.
#103
Got Another Rotary
after reading those threads I am utterly convinced that they were not using a TCW3 compatible Pre-mix and instead were using a cocktail parties worth of different mixes...
For example one said he was using:
ALL BAD BAD BAD and should not be using even in piston powered car. Hell Maxima 2 is not even for automotive use, but rather for motorcycles without any emissions or even fuel injection equipment.
Hell they might as well been using MMO.
If you put crap in your gas tank, your car will break.
For example one said he was using:
ALL BAD BAD BAD and should not be using even in piston powered car. Hell Maxima 2 is not even for automotive use, but rather for motorcycles without any emissions or even fuel injection equipment.
Hell they might as well been using MMO.
If you put crap in your gas tank, your car will break.
Even though you recommend any TCW-3, although fine oils, you still have to be careful as not all of these are automatically cat-safe either (assuming you have one)- I would recommend contacting the supplier to see what they say on it being cat-safe before using. For instance, I was curious about Bel-Ray from my motorcycle days, so I contacted them about their huge selection of 2-cycles and the only one that was cat-safe was the Si-7 product, which is a decent oil, but is NOT their best protecting product.
That is why I recommend people staying with the proven ones that have shown success and no long term issues so far - IRP and AMSOIL Saber Pro seems to have shown this so far.
BTW - I know MMO is a polarizing product in that people either love it or hate it, but boy you really hate it, don't you?
#104
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I'm not sure how most feel about MMO, or who even thought about using it prior to reading this thread. I'd just like to reiterate that i've been using it for the last 30,000 miles on a 80,000 mile engine(8,000 of which are w/forced induction).
I also used it previously for 40,000 miles on a 70,000 jeep wrangler(inline 6). When I had the jeep inspected and driven prior to selling it, the mechanic said it was the smoothest running jeep w/ that amount of mileage he had ever seen. I have never seen or heard of it causing any problems on my vehicles, nor any others.
I can't explain in a scientific manner exactly how it works, but I can say it has never caused me any problems. I put a quart of it in with every oil change and add @4oz to every tank of gas.
I also used it previously for 40,000 miles on a 70,000 jeep wrangler(inline 6). When I had the jeep inspected and driven prior to selling it, the mechanic said it was the smoothest running jeep w/ that amount of mileage he had ever seen. I have never seen or heard of it causing any problems on my vehicles, nor any others.
I can't explain in a scientific manner exactly how it works, but I can say it has never caused me any problems. I put a quart of it in with every oil change and add @4oz to every tank of gas.
#105
Got Another Rotary
I'm not sure how most feel about MMO, or who even thought about using it prior to reading this thread. I'd just like to reiterate that i've been using it for the last 30,000 miles on a 80,000 mile engine(8,000 of which are w/forced induction).
I also used it previously for 40,000 miles on a 70,000 jeep wrangler(inline 6). When I had the jeep inspected and driven prior to selling it, the mechanic said it was the smoothest running jeep w/ that amount of mileage he had ever seen. I have never seen or heard of it causing any problems on my vehicles, nor any others.
I can't explain in a scientific manner exactly how it works, but I can say it has never caused me any problems. I put a quart of it in with every oil change and add @4oz to every tank of gas.
I also used it previously for 40,000 miles on a 70,000 jeep wrangler(inline 6). When I had the jeep inspected and driven prior to selling it, the mechanic said it was the smoothest running jeep w/ that amount of mileage he had ever seen. I have never seen or heard of it causing any problems on my vehicles, nor any others.
I can't explain in a scientific manner exactly how it works, but I can say it has never caused me any problems. I put a quart of it in with every oil change and add @4oz to every tank of gas.
MMO has been around so long, and Marvel has never been willing to formally release the "formula", that I think MMO is severely misunderstood - that is why I posted the data I had previously to give at least the details that can be found and let our forum members make up their own mind about it.
I do think this lack of actual formula data through the years has let the detractors assume the worst, repeat it over and over, so that at some point it is "assumed" to be true by a broader population that has never even used the product (how many times has this happened in our society).
I also think that some have used MMO and not "felt a difference", thereby concluding it is "snake oil" or does not work - but real evidence is hard to obtain unless we do some real engine teardowns for inspections and measurements.
MMO has been around way too long (with no lawsuits I might add) and has too many success stories to actually be an awful or harmful product. Having lasted 85 years, it likely has some benefits to consider.
BTW - I have read of several RX7 owners (on rx7club - and yes it's controversial there too) that have disconnected their OMP and run nothing but MMO premix and have seen many, many miles of perfect operation. If I recall correctly, there is one that rebuilt his 7 motor and last I read had over 45000 miles on it with no OMP and MMO only used as premix. MMO be doing something right or that motor would have been dead long ago.
Soap box done.
Also, RG - I do think brainstorming and conclusion here on the 3rd injector is significant and could very well be the final straw to show that everyone should be premixing. That said, I apologize for diluting your thread with all the MMO talk - if you want, move these MMO posts to the Premix thread.
Last edited by Jax_RX8; 02-22-2008 at 02:34 PM.
#106
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But much like the people that use a Tornado and insist they get more power, or people that have a strong belief in a god, I am sure that MMO provides some sort of mental comfort for those dollars spent.
As opposed to a good TCW3 pre-mix, where dyno tests have shown a difference. Don't think I have seen any Dyno tests showing more HP using Platinum Gas Saver snake oil or MMO.
And in the case of a RX-8 owner, I personally believe that the engine needs pre-mix. The engine design changes shown in this thread seem to back that up as well as my own testing. But people using MMO instead of a good pre-mix, thinking that it will protect from the same problems, well... they could be deluding themselves.
Even though you recommend any TCW-3, although fine oils, you still have to be careful as not all of these are automatically cat-safe either
Last edited by Icemark; 02-23-2008 at 01:13 AM.
#107
Hmmmmmm.........
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I have the same situation. I've had the dealer check it out and they say the fans are working correctly, but that doesn't really put me at ease. I'm still concerned about the temps. getting too high. I just allow for an extended cool down period after spirited driving when it's hot outside.
I've never encountered any other mention of this issue on the forum
I've never encountered any other mention of this issue on the forum
#108
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I personally believe
Just because I believe it, doesn't make it right or correct for anyone else. It just makes it right and correct for me. With my 25+ years of working on rotary powered vehicles and engines I can only hope to help others with less experience by posting my experience and beliefs here and on RX7Club.
If others choose to ignore that... well then that would be their problem, not mine. You can lead a horse to water...
Last edited by Icemark; 02-23-2008 at 01:08 AM.
#109
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Phew.....my fingers are getting heavy....must....keep....typing................... ...........................I can't go on............................it's getting too deep in here
#112
I don't buy Kool-Aid
+1 Good stuff
#113
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I have advovated the use of pre mix in the rx 8 for a number of years on this forum. However i have learned some lessons.
1- use a good pre mix--several choices out there
2- it is NOT the pre mix that clogs the fp/filters, it is the mixture of the premix and the naturally occuring sediment in the gas you buy. Some areas have more than others, some gas stations will have more than others.
3- the small sump tank within the fp unit(BECAUSE OF THE ABOVE) needs to have adequete gas in the tank to keep it "washed out" if you will, if you let your tank get to 1/4 or below regularly, the sediment over time has a tendeny to settle more in the sump tank area. That can be a contributor to problems.
4- the oem fp will have (within a year) approx 7% less pumping ability than when it was new--pre mix or not. So if you have gone to FI--watch your fuel system closely
5- do NOT use a pre mix and an injector cleaner at the same time. Run a tank of non pre mix gas through the car before the injector cleaner is used.
6- at a track event pre mix all you want! Do keep your car with at least 1/2 tank at all times(not taking about autocrossing)
I would really, really like to have an external filter for this car--but no time to explore doing one.
olddragger
1- use a good pre mix--several choices out there
2- it is NOT the pre mix that clogs the fp/filters, it is the mixture of the premix and the naturally occuring sediment in the gas you buy. Some areas have more than others, some gas stations will have more than others.
3- the small sump tank within the fp unit(BECAUSE OF THE ABOVE) needs to have adequete gas in the tank to keep it "washed out" if you will, if you let your tank get to 1/4 or below regularly, the sediment over time has a tendeny to settle more in the sump tank area. That can be a contributor to problems.
4- the oem fp will have (within a year) approx 7% less pumping ability than when it was new--pre mix or not. So if you have gone to FI--watch your fuel system closely
5- do NOT use a pre mix and an injector cleaner at the same time. Run a tank of non pre mix gas through the car before the injector cleaner is used.
6- at a track event pre mix all you want! Do keep your car with at least 1/2 tank at all times(not taking about autocrossing)
I would really, really like to have an external filter for this car--but no time to explore doing one.
olddragger
Last edited by olddragger; 02-27-2008 at 08:20 AM.
#114
The reason why the Renesis has both of it's oil injectors pointing diagonally towards the sides is actually to lubricate and cool the corner seals which now get exposed to hot exhaust gasses. They don't on a peripheral port engine. The downside to this was that some of this oil doesn't get burned nearly as well as it does getting injected directly into the center of the housing. This could lead to the side seals getting carbon locked. This led to the development of the wedge shaped side seal on the Renesis that helps force carbon out of the side seal grooves. The effects of this oil injection technique issue is still seen on the Renesis however in the form of carbon buildup in the intake and exhaust ports.
#115
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Thread Starter
As long as you have oil injected into an area that it can't burn off effectively, you're going to get carbon buildup. That's just the nature of the beast. I am wondering though about exclusively premixing. I wonder if it's a good idea. The reason I say this is because if those oil injectors are pointing sideways to help lubricate and cool the corner seals because the old locations didn't, using premix only wouldn't seem to accomplish the job. It would seem to deal with one problem but leave another. Based on this it would seem that leaving the oil injectors functioning and also premixing with a small amount should be the best compromise. Because the oil metering system stays working, anyone adding premix should only add a very small amount. There shouldn't be any reason why anyone would need to premix an amount that is based upon a nonfunctioning oil metering system.
Keep in mind this is still speculation on my part. I'd personally like to see a Sohn omp adapter used with an external tank of 2 stroke AND a small amount of premix. Somewhere around 4 oz. per full tank of gas.
Keep in mind this is still speculation on my part. I'd personally like to see a Sohn omp adapter used with an external tank of 2 stroke AND a small amount of premix. Somewhere around 4 oz. per full tank of gas.
#116
There are many among us who deny any possibility of a design flaw with the existing Renesis.
Maybe Mazda just altered the design to spend some extra cash for the hell of it.
https://www.rx8club.com/rx-8-discussion-3/sticky-petition-mazda-extend-factory-warranty-renesis-100k-miles-years-138676/
......................
Maybe Mazda just altered the design to spend some extra cash for the hell of it.
https://www.rx8club.com/rx-8-discussion-3/sticky-petition-mazda-extend-factory-warranty-renesis-100k-miles-years-138676/
......................
#117
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There are always those people that have no problems. There are also those with problems. I've tried to make it perfectly clear that this is all my own personal opinion based on the overwhelming signs out there that point to this as well as based on the issues that many people have had as well as what Mazda has done to address this area of the engine, and even based on their own published test data regarding this area of the engine. Keep in mind it would have to be a very big coincidence if they didn't make the changes they did based on the known issues and I seriously doubt it was just to spend some extra cash for the hell of it. There are obviously improvements to make to the design if they would go to all the trouble to make such radical changes. If something has no design flaws, there's really no reason to go change it.
I don't think anyone out there can deny ANY possibility of a design flaw. I don't care what engine it's with. There is always some possibility.
I don't think anyone out there can deny ANY possibility of a design flaw. I don't care what engine it's with. There is always some possibility.
#118
As long as you have oil injected into an area that it can't burn off effectively, you're going to get carbon buildup. That's just the nature of the beast. I am wondering though about exclusively premixing. I wonder if it's a good idea. The reason I say this is because if those oil injectors are pointing sideways to help lubricate and cool the corner seals because the old locations didn't, using premix only wouldn't seem to accomplish the job. It would seem to deal with one problem but leave another. Based on this it would seem that leaving the oil injectors functioning and also premixing with a small amount should be the best compromise. Because the oil metering system stays working, anyone adding premix should only add a very small amount. There shouldn't be any reason why anyone would need to premix an amount that is based upon a nonfunctioning oil metering system.
#120
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Check these pics of expo's old apex seals out. This is a post in his rebuild thread that Rick Engman and Mazmart did. Look at how bowed the seals are! The middle is where all the wear is. The outsides where the oil injectors actually spray is where the least wear is. This is a motor with slightly over 100K miles. I know he did use some form of premix for track days but I'm not sure if he always used it though. It's still scary and not a shape we usually see apex seals take until double this mileage!
https://www.rx8club.com/showpost.php...&postcount=202
https://www.rx8club.com/showpost.php...&postcount=202
#122
Out of NYC
iTrader: (1)
Check these pics of expo's old apex seals out. This is a post in his rebuild thread that Rick Engman and Mazmart did. Look at how bowed the seals are! The middle is where all the wear is. The outsides where the oil injectors actually spray is where the least wear is. This is a motor with slightly over 100K miles. I know he did use some form of premix for track days but I'm not sure if he always used it though. It's still scary and not a shape we usually see apex seals take until double this mileage!
https://www.rx8club.com/showpost.php...&postcount=202
https://www.rx8club.com/showpost.php...&postcount=202
Fred, Do you think the wear has anything to do with the oil weight that Mazda recommends for North America Market ?
I have been using 5w30 since 5K miles. Premix maybe when I was 26 K miles.
#124
Administrator
i disagree on the use of the term "design flaw". but its merely a semantic arguement. clearly this is an evolution in the design of the Renesis. but its not like they had 3 oil injectors previously and then said"eh we dont need it here" and then found it they did.
they simply used a design that seemed to work fine at the time but after years on the market they have found a design that works better.
its like calling 2 valves per cylinder a flaw because 4 valves per cylinder works better.
they simply used a design that seemed to work fine at the time but after years on the market they have found a design that works better.
its like calling 2 valves per cylinder a flaw because 4 valves per cylinder works better.