Own A Mazda Rx8? Here Are Few General Maintenance Tips For Your Rotary Engine!
A rotary engine can be one of the most reliable and trustworthy motors in the world provided you give it proper care that it deserves. Having only a small number of moving parts, it does not have usual breakdowns and headaches related to a piston engine. Mazda Rx8 is one of those sports cars that were imported in relatively high numbers due to its smaller engine cc, hence low import taxes. So if you own a Rx 8 here are few things you need to keep in mind to make sure your engine doesn’t give up on you in the middle of the road.
Also Read: Why You Should Stop Spraying Oil Under Your Car
Oil changes
With all automobiles, an oil change is supposed to be one of the most significant and vital regular maintenance steps. The used oil should be completely drained and replaced with correct viscosity motor oil. A rotary engine is lubricated very differently than a conventional piston engine. Mazda recommends its own Mazda 5W30 Dexelia Ultra engine oil. Rotary engine experts in other countries recommend any good brand semi-synthetic 10w40. But here in Pakistan, it is usually recommended to stick with the regular 20W-50 mineral oil. The length of setting up a new oil change should be every 3,000 kilometers. We have a lot of dust and impurities in our fuel. So it is better to be cautious with the oil changes. And keep checking your engine oil level regularly since you actively burn engine oil during the process of running the motor.
Cooling and other maintenance
Rotary engines require a little more care considering they are different than your average piston engine and rev at higher RPMs. And bad or irregular cooling can really hurt your rotary engine. Make sure you get the best coolant for your car and keep checking the coolant level. You do not want to overheat your rotary engine. A piston engine will survive an overheat. You might just get away with a gasket change. But rotary will not forgive you that easily if you overheat it.
Also, keep in mind to check the spark plugs after every 10,000 km. Rotary engines are prone to carbon deposits relatively quicker than piston engines. Carbon can be bad for your apex seals. Rev the engine now and then to make sure you don’t let the carbon to deposit. Rotary engines love to rev anyway. So don’t worry when you redline it for few seconds.

Also, make sure you inspect the air filter after every oil change and replace it when dirty. Other than that, keep an eye on the engine bay for any oil leaks, greasy or oily marks, or any sort of leaking in the garage where you park your car. Keep an eye on belts as an extra precaution.
Compression testing a rotary
In a piston engine, you have rings to make compression when the piston goes upwards for a spark plug to make a bang. In a rotary engine, you have apex seals. Apex seals are small blade like wedges mounted on the three corners of a rotor. Those seals keep a surface contact with the inner lining of the cylinder. With the passage of time, the seals drop the integrity of a contact, and you start to lose the compression. And that’s why, get your engine compression tested. Here are the PSI numbers of a healthy rotary engine:
- Normal compression – 110-150 PSI
- Minimum acceptable pressure – 75 PSI
Rotaries can be as reliable as a piston engine. The thing is, since they are a different breed than a piston engine, they have different maintenance requirements as well.
Mazda recommends 5W-30… experts in Pakistan says 10W-40 and you recommend 20W-50. How about pouring honey in the engine coz the engineers who designed the engine are fools :-/
using small amount of 2 stroke oil in fuel also protects that engine.
Regarding the Engine Oil, its better to top up every week if its a daily
driver or every 300Km.. It should have at least 200-300ml lesser oil
since Rotaries burn the oil (one of the reasons Synthetic Oil is not
recommended as its not good at burning). I used to keep mine topped up
with oil every week & regular oil changes after every 2800km during
Hot weather to be on the safer side.
In terms of cooling, its
always better not to use the local green coolant, invest in a good
coolant like Zic Red series. The plugs should regularly be cleaned sine
any weak plug will cost you a Ignition Coil & its not very easy
& cheap to get by..
Overall a nice topic & a needed one for rotary freaks 🙂
Yeah that’s absolutely right, as it really helps with lubrication and carbon deposits – probably even more than the onboard OMP. About 10ml per liter of high octane fuel is a great ratio to start with.
Motor oil thins as it heats and thickens as it cools. It really has to do with operating temperatures. In Japan and America the weather is temperate, you could go with thinner oils as the oils never really ever get hot enough to the point where it starts to break down (and in turn stop the wear on the engine). As your temperatures go up, like we have here in Pakistan, the heat exchange within the thinner oils at higher temperatures cannot prevent the engines from wear, so it’s much safer to go with a more viscous engine oil.
explain how a rotary engine works in your next article? That will be helpful