ive been using premix with my FD for 2yrs already and so far id say its been working out pretty nicely. i normally use valvoline 2 cycle oil and i keep it in the driver's side bin (i got my battery in the other) in a plastic bag along with a funnel.

funny story: i am at the gas station one day measuring how much oil im puttin into the bottle (it has volume labeled on it) to dump into the fuel tank. the gentleman at the next pump is watching me curiously as i open the tank and put the funnel in. when he sees me about to dump the 2 cycle into it he shouts at me "hey! thats oil! you dont put that in there with your fuel what are you doin?! that car of yours is gonna get messed up!". i reply "its a rotary!" lol.

anyway, i highly recommend everyone to premix with their fuel, there are some things the manual does not tell you when it comes to this car. when we broke my engine apart in '08 for rebuild the carbon was there but not as bad. it appeared similar to the rotor that howard illustrated in his 1st post. doing this really does help!

 

 

tell him you have a big weed eater under the hood

 

next time something like this happens ill be sure to bring that up hehe.

 

I've been pre-mixing with Amsoil Interceptor for several years now. It was originally developed for two strokes with power valves and I had good results with it in my GP1500R waverunner (which makes ~ 200 hp)

 

howard,

I have few questions about pre-mix...

One, Phase separation of oil and gasoline over time. What is your thoughts on that?

Two, 2Cycle oil with now most common E-10 Gasoline.... What is your thoughts on that?

Personally, I agree that clean oil being injected is better than dirty. But at the same time, I know REWs with 100K miles on original engines that runs fine. If "EOP" is factually real, than I would think mazda would of done something about this over past 40 years and not put more oil jets on the newer version of Renesis. Again, I'm no expert but until some sort of scientific side by side testing is done with same external condition, its still one person's word vs. another.

Also, isn't your engine see high revs?? Isn't that what we hear all the time about how to reduce carb build up?? So, again, I can't really put my finger if getting rid of EOP and pre mix is the results of your clean engine or fact that your engine sees high rev on the track...

 

Phase separation is not an issue unless you plan to store the car for over a year. I keep my two stroke MX bikes and waverunners stored six months at a stretch and I've never seen it.

Four stroke oil injection was a always a really bad idea by Mazda. I'm always amazed by people who whine about pre-mixing, it literally takes 15 seconds.

 

Not whining, just don't think its necessary.

 

It causes deposits, which has been documented for years before this thread, what more proof do you need? 4 cycle oil is not designed to burn, 1+1=2

 

I'd like to see testing done too, but I think to do so reliably would be expensive. You can't compare one FD owner's car with another. Too many things vary with the owner and location.

Perhaps, if you collected statistics on engine mileage and compression readings, while grouping the engines by owner age groups, driving conditions, and premix/EOP... youmay be able to get some useful data.

I would bet that the average compression and mileage of a pre-mixed engine would be higher than with only an EOP... but that's just a slightly educated hunch.

You could even poll veteran rotary racers or aviators and ask them how many hours they got out of their engines and whether or not they used pre-mix.

I would bet mazda has data on this subject, but we'll never see it.

 

LOL! Well, I ran Castrol Syntec oil in my FD for 2 years, than Mobile 1 for a year before my coolant seal went out and I saw very little carbon build up when torn down. I've also torn down several motors with 50-60K miles with coolant seal failure with EOP and saw reasonable carbon build up.

In my opinion there is no side by side scientific experiment that shows significant advantage of running 2 cycle.... as no one engine is ran equally compare to another. That's the point I'm trying to say. Also, you are correct, it takes 15 seconds to add 2 cycle. If Mazda really thought that 2 cycle helped this much, I would think developing an external tank that you could put a quart of 2cycle that dispenses into fuel tank to save engines... I mean, how many miles do you think a quart of 2 cycle will last? I think that would of save them millions dollars on replacement engines. But did Mazda do that?? I'm sorry.. I don't have resources like Mazda to do such scientific testing nor R&D... And as someone in scientific field, I can't just go by someone's word when I myself have seen no significant problem with "EOP".

 

too many variables for anything that would hold up. gas quality, gas octane, oil type, oil weight, driving styles, etc... too many variations to get anything really worthwhile.

plus, you'd need a min of 30 similar vehicles to establish a baseline bell curve.

 

I have beef with the recommendation of most to run about 1/2-1oz of premix per gallon of gasoline. That's fine for supplemental lubrication but is far from adequate if you have removed the OMP. Most two-stroke oil companies recommend a fuel/2-stroke-oil ratio of about 40:1, or about 3oz per gallon. If you think the rotary is a special case you're fooling yourself. To achieve effective combustion chamber lubrication with pre-mix only you will need to mix 3oz of oil per gallon of fuel.

"But then it will smoke like a two stroke"
Yeah, that's the point. That is the result of fuel-based lubrication. Might I suggest you use a smokeless 2-stroke oil like YamaLube.

 

"Phase separation of oil and gasoline over time."

as per DaveW....

"Dale, while I'm not a chemist, or lube expert, I have some knowledge gained from experience and working as an engineer in a rubber/chemical lab (Bridgestone Research) for 37 years, so:

2. A high-quality 2-cycle oil should never separate. These oils are designed to be thoroughly miscible (able to be easily dissolved and stay dissolved) in gasoline, and will stay suspended for years, assuming that the gasoline, itself, is not so old that it turned to varnish due to the presence of oxygen."


i would echo an earlier poster, i think it was Banzai, who points out that our fuel systems do a fabulous job of further mixing. perhaps some are not aware that our fuel does a loop... it gets pumped from the tank by the fuel injectors and that fuel that isn't used recirculates back to the tank. wow, a Bassomatic without the Bass.

i don't have an answer for you on the alcohol side of our current fuels other than to say it has worked for me over the years.

your larger question is certainly a good one...

the fact that Mazda did add an EOP speaks to the need for additional lubrication, especially w the increased output from the turbos. what were Mazdas options?

1. do what they did... EOP

2. EOP but drawing from a clean reservoir of 2 cycle (ashless) oil. i think it is probable that Mazda decided that most owners would think the additional oil tank both a bother and somewhat weird. how many would keep it filled? so they did the deal w the devil and hooked it up to the crankcase.

it is not my contention that running the mazda setup is always fatal. the same day last week that i disassembled a 22,000 mile motor i happened to disassemble another motor that had 20 something thousand miles.

the rotors pictured in post one came from an automatic trans car. the other motor was a 5 spd.

here's a picture of the other (5 spd) motor's rotors...



as you can see not as bad and i have consistantly agreed w other posters in this thread that if you lean on your motor a bit it should help the carbon issue.

still, half of the motors i disassemble have stuck seals due to carbon and all have too much carbon. further, considering how bad crankcase oil is after a few hundred miles i would never let it get anywhere near my motor's interior. i will also not build a motor w the EOP operable.

but that's just me.

 

Complete and utter nonsense.

The seals require only a small amount of lube. I've been mixing 0.5 oz per gallon for at least 5-6 years and my motor is just fine. If anything, even that amount is overkill for the street imo.

Which has NOTHING to do with lubrication of apex seals in a rotary. The FD has wet sump lubrication of internals, a two stroke dirt bike does not....get a clue.

 

-Barban-

I thought the same thing but... you have to think how much oil is injected by the oiling injectors

 

So after following this thread i been thinking of some things. (s4 engine) I did the 2-stroke injection omp mod. I have 4 1600cc injectors so the fuel/oil ratio is way off. My idea is to just run the 2 stroke injection like so, also pre-mix 1/2 oz - 1gal. of gas. good idea/ bad idea opinions!

 

The OMP injects oil directly onto the friction surface. A pre-mix system add's oil via the fuel injectors in mist form. Thats why it takes so much more. It is not a direct application. Most of the injected oil will burn off without lubricating anything.

 

40:1 is a small amount of lube in an injection system. Some companies recommend ratios as low as 20:1
They're your housings and you can wear them out and replace them all you want. Care to share how many miles you've put on your car in that time?

It has everything to do with the lubrication of the apex, corner, and side seals. Do some research. A 120:1 or even 240:1 ratio(1 to 1/2oz per gallon) doesnt lubricate anything at all. In fact: a 40:1 mixture doesn't lubricate 2-stokes well enough to keep them from wearing out reciprocating/friction parts at an accelerated rate.

 

Now to make things more complex...

E10 fuel vs E85 & E100 Fuels...

Do you think we would have to increase the ratio, in order to compensate for the higher percentage of ethanol in said fuels?

Wondering if the petro based fuels act a a partial lubricant VS the ethanol based fuels.

Also, do you think 2 stroke oil mixes (and stays mixed) in alternative fuels as well (and for as long) as it does in E10.

 

I've done the research and I have first hand experience. You don't know what you're talking about, it's just that simple. My engine has about 30k miles on it, with excellent compression. 0.5 oz per gal is perfectly fine for the street.

This is also complete nonsense. Most of the GP1200R (waverunner) guys on Greenhulk.net have been running 40:1 for many years in the triple cyclinder two strokes and the motors look great at tear down (assuming you're running a quality oil).
http://greenhulk.net/forums/showthread.php?t=116918

Two stroke oils, like everything else, have come a long way in the last 20 years.

 

Yeah, I looked further into it and found out that it has been done before but with a little more modding for those who are still interested. I searched and found this;

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/oil-drain-pipe-hitting-connector-after-omp-adapter-install-744703/

I think David made mention of turning the omp at an angle to position the connectors out of the way and then to tap new holes to put the omp back onto the car. But this information is for those who wanted to know what complication might be met if you went this route.

 

Not to jump in the middle of who knows most about 2 stroke oil, but Barban can you provide a link of claims by a 2 stroke oil company that straight up recommends this 20:1 or 40:1 premix ratios? I have always read from the racing groups that a 50:1 to 100:1 is more than adequate for lubricating your seals when the OMP is deleted and that is for racing applications - typically 120:1 for street.

I am not saying anyone is right or wrong, but to keep things more scientific I am sure other like myself would want to read where these recommendations have come from as it may shed some more light on the subject. As you know from this thread I have been premixing but have yet to eliminate the OMP.

 

We disassemble between 75-100 engines every year, out of those there will only be a few that have stuck seals. Most have blown seals.

The engines with stuck seals are:

1. Rusted in place from sitting with a bad coolant seal for extended periods of time

2. J-spec engines that are sent to us for rebuild prior to installation. Again sitting for extended oeriods of time.

3. (Very rare)- carbon locked engines from never taking the car past 4000 rpm.

The J-specs are the most common simply because they have been sitting in junkyards/warehouses in Japan for who knows how long, basically drying out.

The US engines that we either remove or have shipped in that were recently running rarely (if ever) have any stuck seals.

As I have been saying from the beginning of this thread driving style has more to do with excessive carbon build up then anything else.

I have stated my biggest problems with the OMP:

1. When using with the PFC there is no notification of failure besides an engine with no compression

2. Can't prove that the PFC maintains the proper oil ratio with larger injectors.


when running four huge injectors, pre-mix is a must. As you suspect your ration is way off. In your case you have a mechanical OMP which certainly will not compensate for the addition fuel flow.

We run 1 oz/ga. in all our cars, I have personally lost compression on my own car a few years ago running only 1/2oz/ga at only 15psi, sagged the apex seals in one pull with water injection as well. Ran 1oz per gallon even since and have never had any problems even at 27-28psi.

Ethanol based fuel requires different/special 2-cycle, your normal oil will not mix at all. I have concerns about mix ratios with these fuel also, as they tend to dry out seals simply due to the nature of the composition. It is alcohol after all.

 

just curious, if i switch to premix and remove the eop, which it looks i',m going to do, how often is everyone changing their crankcase oil?