Hi all,
I topped up a little castrol synthetic oil (0w/40) for my rotary yesterday, but the original oil in the tank should be 76 i guess which is mineral, cause the last time i do oil change was at the WGT. Was that okay if i had mixed an amount of 300ml into the tank? I think I was very stupid that mixed up mineral and synthetic without asking somebody...
Many thanks
Mark
Rotary engines inject Oil into the combustion chamber so you must use mineral oil as synthetic doesnt burn. Castrol GTX is fine. An oil change will cost you 12 quid so it might be worth changing it, you cant change it too often in a rotary.
Cheers mate,
But now is I\'ve already mixed a little amount of synthetic into mineral, will i or she be in danger if i drive her out?
Synthetic is ok if it is the right one!
As the Castol is an untested oil for rotaries I would suggest you change it.
Castrol GTX mineral from halfords is fine for these engines,so is Millers mineral oil.
It is not true Antony that synthetic does not burn.Some synthetics like Royal Purple are reccomended for the rotary engine and whilst they are not cheap they are just about the best oil you can get for your engine.The RX8 engine uses synthetic oil.Some oil is still injected into the engine.
Gary Marks at "Rotary Tarts" ,see banner above,is a supplier of Royal Purple oil.
With synthetics you have to be careful of what type you use in your engine because the oil control rings in the sides of the rotors have "O" rings in them that may break up due to some oils in the synthetic ranges being harsh on them and basically decomposing them.This would elad to a very smoky engine,Which would then need to be ttorn down and rebuilt.
Kind regards
Carl
QuoteOriginally posted by Carl
the oil control rings in the sides of the rotors have "O" rings in them that may break up due to some oils in the synthetic ranges being harsh on them and basically decomposing them.
Carl,
Do you know what the "O" rings are made of?
If you can tell me that, or if you have a note of godd and bad synthetic oils, I can ask a family member in the oil business to try and work out what chemical in the synthetics causes the problem.
Gregor
QuoteOriginally posted by Shark
Carl,
Do you know what the "O" rings are made of?
If you can tell me that, or if you have a note of godd and bad synthetic oils, I can ask a family member in the oil business to try and work out what chemical in the synthetics causes the problem.
Gregor
Hi Gregor,
The inner "O" rings are made of a type of silicone.I could give you a sample if you like?Mazda have changed them over the years but they are interchangeable.
I use a different material that is fine with any synthetic on some rebuilds in order to not have the problem.Usually these are race orientated engines.
The outer "O" rings are fine with synthetics.
We have used Millers semisynthetic oil and have also had no problems.
Kind regards
Carl
Sample probably no good, the family member concerned is in the US. His first brand new car was an RX-4 so he knows a rotary engine!
I\'ll ask him if he can think of any compound used in synthetics that would not be good in combination with silicone. Will post if I get anything useful back.
When I last spoke to him the information he gave me was as below. Ber interested to hear if that fits with your experience/view?
QuoteA good quality synthetic with a PAO basestock will handle heat much better than a conventional oil can. The oil can go to 425 degrees F. (of course). Just make sure you are use a good quality synthetic, just because it says synthetic on the label does not mean they are all the same. I believe Motul, and Repsol are two that come to mind that should be available over there, also if you can get it Mobil 1 is also good. Let me know if you have any other concerns and I will see if I can get some info that is rotary specific.
He also contacted the technical guys at AMSOIL (//WWW.lubedude.info) and their response was
QuoteIn response to your inquiry, the apex seals on the earlier rotary engines were not compatible with most synthetic formulations back about 20 years ago. Synthetics have come a very long way on the last 20 years or so and the use of AMSOIL will NOT adversely affect these seals. Not only that but seal material has come a very long way also! This is an old story that has hung on for years and even though it is no longer true, the old myth still exists.
Bottom line is you most certainly may use our advanced formulations in the rotary engines.
The apex seals are most defintiely not the problem.
The material they use now even in the RX8 engine is identical to that used nearly 30 years ago.cast iron alloy that is chill hardened.I have had the seals analysed for the make up.
The shape and sizes of the seals have changed.
The oil control rings do not get affected by all synthetics,Amsoil is another make that is known to be fine on rotaries.
The statement about not all supposed synthetics are really proper synthetics is why I have said to be veryu careful about what you put in your engine.
I was just trying to keep it simple so as not to confuse too much.
It is not a myth that some oils still affect tthe oil contol rings "O" rings.I have personally pulled down engines with this problem.Oil type I am convinced was to blame.Just use the right ones,don\'t guess.
As I said there are good oils out there that are synthetic,the ones you have mentioned will be fine.
How available are they to the average user?
That is why I tried to keep it simple too.
Kind regards
Carl
Latley i have been using Halfords own mineral Oil and i find this to be excellent and the car runs so much smoother than when i was using Castrol Mineral oil.
and its cheaper.:p
I went from using that cheapo Halfords mineral oil, to Castrol and found the castrol to be smoother and nicer. I think the fact that you are replacing gunky black oil, for nice new urine-coloured oil means that one always thinks the change is for the better!
I just decided to use a more \'proven\' oil.
Alex.
Its all in the mind, you are replacing black gunky oil with nice clear new oil, no way can you ever feel the diff driving the car. You will only know when your engine tells you. cough,cough,splutter,pop:D
i used valvoline TURBO V 10w40 mineral in mine and it has been a magic carpet ride ever since. i read the advice of an american member of the rx7club.com. good thing is that this oil only costs £11 for 5 litres..finding the stuff is a bit more of a mission though. i noticed that my oil gets dirty too quickly now with the fuel smell also very present, its the third oil change ive done in 3 months!! also sometimes i can smell oil burning when i stop at some traffic lights or pull on the drive for the night. am i being paranoid??
QuoteOriginally posted by RobbieRX-7
i used valvoline TURBO V 10w40 mineral in mine and it has been a magic carpet ride ever since. i read the advice of an american member of the rx7club.com. good thing is that this oil only costs £11 for 5 litres..finding the stuff is a bit more of a mission though. i noticed that my oil gets dirty too quickly now with the fuel smell also very present, its the third oil change ive done in 3 months!! also sometimes i can smell oil burning when i stop at some traffic lights or pull on the drive for the night. am i being paranoid??
Well it could be side seal wear or even your oil control ring "O " rings breaking down and letting some of the petrol through into your sump.
hope not for you.
Kind regards
Carl
yeah mate..thats what i thought..sooo how much will you do a rebuild for? bloody hell thats cheap!! £250..DONE..i will pop it round tommorrow bud. :rollin
Add more than an extra nought into the figure and you will be nearer the mark.lol
Kind regards
Carl