What is an FCs4...FCs5?
I have a 91 non turbo is this an FCS4 or 5?
I also have a 90 Turbo..what is this?
Can you use slick 50 in rotary engines? I know you can use synth oil..but only good ones like Moble 1.

Okay..4 questions

 

where are you getting FCS4 or FCS5 from? there are 2 different models of FC, there were S4's and S5's
but to my understanding, both the S4 and S5's had the chassis code FC3S
a 1990 TII is most likely a S5.

as for the type of oil, i have no idea. i was told never to run sythetic when i first got my 7. so i just run natural oil. never caused me a problem. I also believe sythetic doesnt burn as clean as natural motor oil so it may give you some problems when trying to pass emissions
come on forum buddies, correct me if im wrong

 

Wlecome to the forum but don't forget to read the FAQ, you'll find the awnsers to most of your questions there.

1986-1988 = Series 4 = S4 = Zenki
1989-1992 = Series 5 = S5 = Kouki

Good quality synthectic oils are perfectly fine, in fact they burn better than conventionnal oils.

 

Not to mention they wont leave as much carbon in your engine.

 

The 1990 is indeed an S5. You need to read up in the FAQ section all about rotaries.

I would not recommend running Slik50 (or any oil additive) in a turbo rotary. Synthetics are OK as long as they are high quality synthetics, Mobil 1 for instance. Don't use synthetic blends like Syntec.

You're supposed to change oil in a rotary every 2500-3000 miles anyway, so why even use a synthetic. My recommendation....use a good quality dino oil, Castrol GTX, 10W-30 in winter and 20W-50 in summer and you should be fine. Keep the oil level topped off between changes. Check the oil level at every fill up.

 

Where would that particular FAQ section be listed? I've tried the one on both the home page and the forum specific, but all the info I've seen in there is site mechanics specific.

 

I really do appreciate all the advice everyone has provided.

 

Nevermind...I found it.

 

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