MMO-Caution as a premix
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MMO-Caution as a premix
Just got my car back and another new engine and my dealership is very knowledgeable about the rotary and apparently visits this forum often 
. Most of the techs there either drive a rx8 or a fd7 so they know all about the issues and about premixing. Before sending in my blown core they took it apart to see what type of failure i had, and right off the bat they noticed the inside of my engine was pristine (No carbon build up). He called me and said whatever you used as a premix, stop using it. He said it look as if it was just a straight solvent being injected into the engine which kept it free of carbon but it looked like it prevented the oil to properly lubricate the housings. He told me that he used to premix with Idemitsu and thats probably the only one he personally recommends but he also stopped using that one because it kept clogging his fuel filter and eventually he lost his first engine to running lean because of a fuel issue. On his re-manufactured engine he simply increased his omp flow and runs 10w-30 in his engine doing changes every 3k miles and he currently has 110k on that engine. He told me it really seems like luck of the draw with the engines because he has seen some come in for basic maintenance that are treated like ****, barely get oil changes, and still run the 5w-20, yet they have 140k on them and run perfectly.....
They need to send the engine out tom but he said he will take some pics of the core and either send them to me or post them himself. He is a member but its apparently a big NO NO to get on these forums and give his opinion if they go against "warranty"
. Most of the techs there either drive a rx8 or a fd7 so they know all about the issues and about premixing. Before sending in my blown core they took it apart to see what type of failure i had, and right off the bat they noticed the inside of my engine was pristine (No carbon build up). He called me and said whatever you used as a premix, stop using it. He said it look as if it was just a straight solvent being injected into the engine which kept it free of carbon but it looked like it prevented the oil to properly lubricate the housings. He told me that he used to premix with Idemitsu and thats probably the only one he personally recommends but he also stopped using that one because it kept clogging his fuel filter and eventually he lost his first engine to running lean because of a fuel issue. On his re-manufactured engine he simply increased his omp flow and runs 10w-30 in his engine doing changes every 3k miles and he currently has 110k on that engine. He told me it really seems like luck of the draw with the engines because he has seen some come in for basic maintenance that are treated like ****, barely get oil changes, and still run the 5w-20, yet they have 140k on them and run perfectly.....They need to send the engine out tom but he said he will take some pics of the core and either send them to me or post them himself. He is a member but its apparently a big NO NO to get on these forums and give his opinion if they go against "warranty"
Just got my car back and another new engine and my dealership is very knowledgeable about the rotary and apparently visits this forum often . Most of the techs there either drive a rx8 or a fd7 so they know all about the issues and about premixing. Before sending in my blown core they took it apart to see what type of failure i had, and right off the bat they noticed the inside of my engine was pristine (No carbon build up). He called me and said whatever you used as a premix, stop using it. He said it look as if it was just a straight solvent being injected into the engine which kept it free of carbon but it looked like it prevented the oil to properly lubricate the housings. He told me that he used to premix with Idemitsu and thats probably the only one he personally recommends but he also stopped using that one because it kept clogging his fuel filter and eventually he lost his first engine to running lean because of a fuel issue. On his re-manufactured engine he simply increased his omp flow and runs 10w-30 in his engine doing changes every 3k miles and he currently has 110k on that engine. He told me it really seems like luck of the draw with the engines because he has seen some come in for basic maintenance that are treated like ****, barely get oil changes, and still run the 5w-20, yet they have 140k on them and run perfectly.....
They need to send the engine out tom but he said he will take some pics of the core and either send them to me or post them himself. He is a member but its apparently a big NO NO to get on these forums and give his opinion if they go against "warranty"
. Most of the techs there either drive a rx8 or a fd7 so they know all about the issues and about premixing. Before sending in my blown core they took it apart to see what type of failure i had, and right off the bat they noticed the inside of my engine was pristine (No carbon build up). He called me and said whatever you used as a premix, stop using it. He said it look as if it was just a straight solvent being injected into the engine which kept it free of carbon but it looked like it prevented the oil to properly lubricate the housings. He told me that he used to premix with Idemitsu and thats probably the only one he personally recommends but he also stopped using that one because it kept clogging his fuel filter and eventually he lost his first engine to running lean because of a fuel issue. On his re-manufactured engine he simply increased his omp flow and runs 10w-30 in his engine doing changes every 3k miles and he currently has 110k on that engine. He told me it really seems like luck of the draw with the engines because he has seen some come in for basic maintenance that are treated like ****, barely get oil changes, and still run the 5w-20, yet they have 140k on them and run perfectly.....They need to send the engine out tom but he said he will take some pics of the core and either send them to me or post them himself. He is a member but its apparently a big NO NO to get on these forums and give his opinion if they go against "warranty"
...well.. what were you using as premix? So others know what to avoid.
Last edited by Lord ET; Mar 11, 2010 at 12:08 AM.
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I used MMO. They are not "supposed" to take it apart but they are fellow rotorheads who are curious. And that dealer is amazing, There are like 2 people there that do suck though and i never bother talking to them because one is a bitch and the other will just be rude and try to void your warranty so let me know before you take it in so i can try to direct you to the proper person 
You should bold the important part lol.. i almost missed it. That's pretty scary, if it's pretty much displacing the engine oil, or just dissolving it. I wonder if FP+ is that extreme as well..
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I ran 4oz a tank. Now my engine failed at just about 15k miles on it. The "direct" cause of the failure was an injector not injecting enough fuel do to a small leak and one of my new ignition coils completely shitted out after 12k miles and that combo caused a super lean misfire and POP. His theory is that with my conditions it looked like i was doomed for failure, but the housing and seals seemed really worn, especially for only having that little amount of miles on the engine and it was both housings that looked like that, and not just the front one that failed.
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Ive never used Idemitsu so i wouldnt know, my tech said he just had issues with it clogging his fuel filter but he felt like it was the best route as far as premixing goes. As far as the measurements im not sure how that works. Is Mazda North America going to break it down and do test and if so would i be able to get the results?
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if they actually opened that motor the dealership isn't going to get paid for a motor. There are a minor handful of dealers who are allowed but they wouldn't say "just because we wanted to look" I'd ask you if it was a certain dealer but that might get them in trouble and besides, someone from Mazda will see this soon any way and see your location and know which dealer it was. I don't want it to look like they got told on.
having said that- MMO didn't stop the proper lubrication of your engines innards. It helped lube them AND reduced the production of carbon deposits.
having said that- MMO didn't stop the proper lubrication of your engines innards. It helped lube them AND reduced the production of carbon deposits.
^I think Zoom44's interpretation is at least equally likely as the dealer's. Until somebody puts a straightedge to the seals and verifies the wear rate is much greater than is typical for a 15k motor (does anybody even know what is normal wear for a 15k motor?) I think it is speculation to indict MMO.
1) Pre-mix does NOT clog your fuel filter. Crap clogs your fuel filter. Whether or not pre-mix exacerbates the crap issue remains to be verified.
2) Do NOT put MMO anywhere near your motor for any reason in any orifice. I wouldn't even use it as tool oil in my air tools.
2) Do NOT put MMO anywhere near your motor for any reason in any orifice. I wouldn't even use it as tool oil in my air tools.