I just changed to Mobile 1 15W-50 yesterday, noticed that the car is a little less responsive. Just wondering if anyone has ever had problem w/ this oil. (fouling the plugs, or gumming up seals, etc.) Mazdatrix says that some synthetics will cause engine failure.

 

Gotta be psycosomatic

 

Change it immediately to (not-synthetic) Castrol 20w50.

Do some research on the forum and other areas about use of synthetics in rotary engines, and which are acceptable and which can possibly ruin the engine.

Make your own conclusions afterwards and then change the oil to the brand you desire.

 

If you're telling him to do research and come to his own conclusions, why are you telling him to change out the oil immediately?

 

I think it's better to go with something more trusted before you do something like synthetic.

Myself, and quite a few other rotary owners in my area all use Castrol 20w50. Some have been doing so for years, and never had problems. Therefore I feel it's a 'safe' oil to choose until you decide switching to synthetic is right for you.

I would add input to my thoughs on sythetics, but I have done a very small amount of searching on the topic. It seems like a gray area.

Icemark suggests a specific type of synthetic, while other reputable owners don't recommend any synthetic at all. Who's to say what exactly is right and wrong? I'm just basing my response on my personal experience and others in my area.

If he has noticed a performance lag of some type, then I would recommend changing the oil back to something more widely used and trusted, and then ask questions. May prevent engine damage if any were to occur.

Please dont flame guys, as I said before I haven't done much research into the synthetic use. I suggested changing the oil to Castrol 20w50 because the owners in my area essentially swear by it. It would be good to use it until the original poster decides to get all the facts about it and then decide which syn to use if any at all.

I haven't done much research into because Castrol is reputable, and cleaner than most of the other crap out there. That's good enough for me.

 

You normally cannot go back to non-synthetic after putting synthetic oil in your engine, but if he pulls it out immediately he should be okay. And remember that the oil cooler has a fair bit of oil in it, so to get all the synthetic back out you will need to do an oil change, drive for five minutes, then do another oil change.

 

Black 13B, for as many posts as you have, one would think you new how to read as well as write. The mineral based oils are only important during break-in, after that I challenge you to identify a single downside to Mobil 1 or any other quality synthetic. Rather than educate you here, why don't you pick up the phone and call MazdaSpeed, Racing Beat, and see what they say.
In brief less wear and lower operating temperatures are considered positives by most
Ordinarily I would not respond so strongly, but you are alarmist, and wrong.
Feel free to respond with test data, and/or facts to back up your advice.
My comments are straight from Steve at Mazda Competition fyi.
Further you did not bother to find out if he is turbocharged with would redouble the importance of using a synthetic.

 

Well Id hate to challenge someone with such a vast amount of rotary knowledge as you, but let me jump in on this. Rotary engines need lubrication inside of the combustion chamber for the seals. So Mazda designed a system that uses the motor oil that you change every few thousand miles and squirts a small amount of it into the combustion chamber. Now motor oil isnt the best and cleanest thing to burn, but it works. Some people, ie me, have disabled this system and use 2-stroke motor oil in the with the fuel so that a cleaner and better burn can insue.
Now sythetic oil doesnt burn very well at all, and it tends to gunk up in the motor, causing terminal failure over time. So it is NOT better to use than mineral oil in a rotary engine.

 

I could say the same to you. Or maybe I couldn't:


As I posted Earlier, I didn't do much research. He said he noticed a power loss or lag of some sort. I merely suggested switching to a 'safeguard' type of oil. One that has been trusted for many years. Then get the synthetic data, and decide for himself.


Again, it was merely a suggestion. I never said "DONT USE SYN! IT'S TEH GH3Y!". I mentioned some reputable owners have suggested to not use syn in a rotary.


I am not an alarmist. I suggested changing it out until he gets the data and decides it's better to use. Do you just jump into running aviation fuel on your turbo without doing any research? Anyone in the right mind would say "Go back to pump gas, and then get the data and THEN decide if you want aviation fuel."



Apparently, I'm not the only one who is incapable of reading and writing successfully. If you would have READ my post, I clearly stated I made my recommendation based upon my OWN experiences, and that I have just touched on the subject of synthetics, and I have no real backround on it's use in rotary engines.

According to his findings, I suggested something based on my own experience.

I'll quote myself here so maybe you'll notice it this time.



.. And?

Refer you to my previous statements

 

What oil did you switch from?

 

Black13B

I see where in2twins is coming from. From your very first statement, you told 87RXGhey7 to "Change it immediately to (not-synthetic) Castrol 20w50". Are you an alarmist? I would think so, given that you used italics to phrase "immediately". Also, 87RXGhey7 was told "Mazdatrix says that some synthetics will cause engine failure." You telling him, to "immediately" change out his Mobil1 for Castrol, implies that Mobil1 is not suitable. Even though you readily admit that you have not done much research on the subject of synthetics.

But as you said, "I think it's better to go with something more trusted before you do something like synthetic." Apparently, 87RXGhey7 felt that he wanted to switch to synthetic and he felt he was able to trust a brand like Mobil1. But you steered him clearly away from synthetic back to dino. Despite this statement :"Make your own conclusions afterwards and then change the oil to the brand you desire."

Your statements are contradictory at times.

Re-read what you posted, and tell me where I am wrong.

 

I switched from castrol syntec (weight unknown)

 

well i dont know if im stupied, but i trust kendal, thats what we ran in all our race cars we had, So why not a daily driver, with kendal 5W-30 non syn, it runs very good and snappy, altho dave atkins said that synthetic isnt bad for a old motor but he said it can be hard on new motors.

 

87RXGhey7

There is a wealth of information throughout this entire forum regarding the use of synthetics. Some people use it, some don't.

My personal opinion, is that the use of current modern synthetics is fine. Just be sure to use one that is a "quality" brand. Don't use a generic brand. I will be using NEO synthetic once my engine is rebuilt and ready to go. Others have used Royal Purple. I think that the use of synthetics stems from the older days, when synthetic was first introduced. The engineering/machining of engines back in the days, were not as exact as they are today. Back then, the introduction of synthetic oil resulted in leaks, due to inexact machining, etc.

Anyways, just use a quality oil in your RX-7 (whether synthetic or not is up to you).

 

87RXGhey7- Synthetic oils usually lubricate better than mineral oil BUT the rotary drinks oil and burns it. There is an internal lubrication system(MOP/OMP Metering oil pump) Some synthetics do not burn cleanly and leave deposits behind that eventually lead to engine troubles. Although some of the better synthetic oils are used on rotary engines(Neo and royal purpul being some of them) The regular brands may or may not burn clean enough and hurt your engine in the long run.

Santiago

 

I'm going to stay out of the sythetic argument. I use it, but that's my problem.

I would say, though, that unless 87RXGhey7 has a TII, I would use oil that is less thick. 10W30 comes to mind.

20W50 is more for TII's.

 

Yup I use 10W 30 all the time I used to use some 10W 40 but switched.

 

If you were using a thinner oil before, then that could explain the response difference, but it shouldn't be very noticeable.

Most of the top Mazda racing teams use synthetic oil in the pre-mix. Some synthetic oils work well, and others do not.

See the Owner's Manual or Factory Service Manual for oil weight recommendations based on ambient temperature.

See the Owner's Manual or Factory Service Manual for oil weight recommendations based on ambient temperature.

True about the break-in. After that, you can use whatever you like.

I will take the single downside challenge.

PRICE!

Oil Math 101 for you people who want to spend your money on synthetic oil for your street car that will see no significant benefit from using synthetic motor oil:

Mazda recommendations for "unique" driving conditions:
Turbo II oil change = Every 3,000 miles
NA FC oil change = Every 5,000 miles

Typical FC engine lasts about 150,000 miles before rebuild.

150,000 / 3,000 = 50 oil changes per TII engine
150,000 / 5,000 = 30 oil changes per NA engine

Typical TII oil change = 5.5 qts
Typical NA oil change = 6.5 qts (one qt added for normal burn-off at 3,000 miles)

50 * 5.5 qts = 275 qts oil per TII engine
30 * 6.5 qts = 195 qts oil per NA engine

Now multiply the qts of oil for your engine times the price you pay per quart.

Example:
TII engine using Royal Purple @ $5/qt = 275 * $5 = $1,375 of oil costs per engine.

Compare to the same engine using Castrol GTX @ $2/qt = 275 * $2 = $550.

The difference between Royal Purple and Castrol GTX is $1,375 - $550 = $825, which just happens to be about the price of a 13B rebuild kit. You guys who like to run synthetic motor oil on the street are probably happy spouting off all the different propaganda statistics about how great synthetic oil is, but I'll take the Castrol GTX and free rebuild kit.

 

Black 13B, Unfortunately your second post(explanation of your opinion)was not visible to me as I typed(I am not sure how the server determines what order to list posts when several people respond at once, I think I began before you, and finished after). Anyway I think that the choice is that of each owner, and that choice should be made following an amount of research which makes the owner comfortable with his decision. I did come on strong because as DOM pointed out you gave someone strong advice without having done the research you yourself recomend(essentially agreeing with what I am now posting).
Black13b, your second post would have been an appropriate first post.
Bdoty311, may I have the source and/or test results as it relates to Mobil 1(the synthetic in question), I would like to learn more about what you are saying. Also I probably deserved a sarcastic poke or two
Pony, I don't think you are right, and you contradict the labeling on every container of synthetic I have ever seen. Can you support your statement so I can learn more?
This is not black and white, I made a mistake by by saying "you are wrong". I still feel that you are, but it is not appropriate for me to phrase it that way on the forum, I apologize.
As for what to use, I like everyone else have made my decisions based on the data that I trust, in this case Racing Beat, Mazda Competition, Atkins Rotary, Petit, and Rotary Performance, not to mention almost every Formula Mazda team I can think of. Either way, in my world of turbocharged high output rotaries the synthetics are the norm. Moving forward I will try to learn more about the residues left behind by certain synthetics.
On balance, for me lower operating temperatures, and the prevention of oil coking on turbo bearings are far more important to me than any amount of buildup I have ever seen in a rotary which has lived its life on synthetics. Further I have never seen a documented failure due to this buildup(I am ready to be educated if someone has the evidence).
once again I am sorry for being so harsh(though accurate). Regards, Carl Byck

 

Evil Aviator. I never thought about the total costs based on price. Thanks!

Pertaining to the main topic,...sorry I cannot provide a picture of this, but Mazdaspeed oil and FEED oil cans say "synthetic" on the side of them.

 

Evil, why not just use synthetic, and skip the rebuild?

 

And, one turbo failure due to bearing failure negates the cost benefit. You win NA, I win turbo.

 

If you think that using synthetic oil will double your rebuild time, I have a bridge to sell you.

So how exactly to you equate Castrol GTX to turbo bearing failure?

I guess the summary of your posts is that synthetic oil is highly recommended for driving your car in Lala Land.

 

TOTAL BS !

Synthetic is just extremely pure motor oil. No more, no less. It has zero ash, there is an open issue with rotaries. I suspect the 'old wives tail' got started by ppl using synthetics that were actually blends. Mobil 1 is fully certified for rotarys.

 

That's not exactly true. Synthetic oil is made from different stock, so it is not just purified petroleum oil. Engine break-in should be performed with a low ash petroleum oil, as stated earlier by in2twins.

The "old wives tail" is from actual problems with non-compatible synthetic oil building up in the rotor, rotor housings, and apex seals, eventually causing striations on the rotor housings. An oil needs to be totally emulsifiable in gasoline, as well as burn cleanly in a rotary engine, in order to be totally compatible with rotary engines. Not all synthetics meet these requirements, as neither of these properties are necessary for use in 4-stroke piston engines, which compose the large majority of automotive engines. There are some SAE papers on this subject if you really want to research it.

Could you please post verification of the Mobil 1 rotary engine certification?