Pure Conjecture As To How To Keep Renesis Healthy (YMMV): KISS Method
 

I will make this super short consistent with the KISS methodology.

My 8 has been uber-reliable now with 8 years of daily driving to its credit.

After much discussion with some techs (including one at Atkins who opined that average life of factory, well maintained Renesis Series I was approx 160,000 miles if reasonably maintained based on MANY 8s he's worked on/with), a rotary-head friend, and my own experience, here's the KISS method for keeping a Renesis I or II healthy:

1) Only buy a manual transmission equipped 8 (two oil coolers definitely beat one for purposes of a rotary motor)

2) Keep oil at or slightly above full increment on dipstick

3) Use dino oil (5W-30 or 5W-20 in hot climates)

4) Change oil/filter every 3k miles (since only half gets changed)

5) NEVER let vehicle operate for any significant period in an overheat state

6) Change coolant every 3-4 years/40k-50k miles max
7) Replace radiator cap with OEM new one at 50k miles
(cheap insurance)

8) Short tripping is EVIL. 10 mile commutes each way minimum are required to lubricate motor, warm cat to proper thermal envelope, and burn off noxious deposits and prevent carbon deposits.


Discuss. Disagree. Agree. Flame away.

Cheers.

While I generally agree with the points made, I think that there are several other major failure points missing completely.

9) You are missing SOHN adapter to stop burning the filthy 4-stroke oil that wasn't meant to be burnt

10) Other parts of the cooling system can fail over time, and need to be replaced periodically

11) Enable yourself to be able to know what the temps actually are in the engine, since you can have a failure before the needle even starts moving

12) Overheating can be fatal within seconds, so "significant period" is misleading.

13) Fuel pump failures can kill engines. Test and/or replace periodically

14) Cat failures can kill engines. Go catless or make sure you regularly check/replace parts that can cause misfires

15) OMP lines can clog if you keep running dirty 4-stroke through them, clean them or swap to a SOHN.


I'll avoid comment on the oil weight choice. I disagree with it, but oil wars are hardly new, or changing anyone's mind :)

No mention of upgrading the coils? Or at the very least swapping OE coils?

I'm in agreement with these additional issues, but I think frequent oil/filter changes (3k OCI) helps mitigate against #9, #10 and #13 are good points and good practice, but not unique to the Renesis...

...and...

#12 is absolutely true. If anything, I should have written continuing to operate vehicle in overheating condition can be catastrophic in a very short time, so I wrote that very poorly.

As to #15, does anyone here think there's a credible oil additive that effectively removes deposits and helps to ensure flow through the OMPs?

OE coils AND plugs (surprisingly) have worked fine in my 6MT. I don't why, but I have 90k plus of daily driving miles and my original motor runs like new.

Using an oil that doesn't sludge up under heat helps significantly. The short list of oils that don't do that is very short indeed. Still, the recommendation of a SOHN adapter eliminates the concern and remains the preferred choice and functionally better than worrying about oil choice and sludging.




While upgrading the coils is something I can agree is a benefit overall, I have trouble recommending it as something that directly extends engine life, even when you have a cat.

How many times have you swapped the OE coils? Before I had the BHR setup I went through 3 sets of OE coils. They work fine but do not last long. They basically became a ware item like plugs and became part of my yearly maintenance.

Ok here goes ........ I think it is a total fallacy that there is any issue with burning crankcase oil . I actually think Synthetic 4 stroke oil does a better job than 2 stroke. .

There ............. I said it ! Let the fun begin . lol

I would agree that 4-stroke would lubricate better than 2-stroke. I disagree that it burns better. :)

And my opinion is that since cooling is the primary function, not lubrication, the penalties of 4-stroke residue is greater than the lubrication penalties of 2-stroke.

Just my opinion.

Well - i didn't mean to imply that 4 stroke burned better - of course it doesn't . But is that an issue ?
As far as the deposits we see at an engine teardown goes - i think the quality of the gas has more to do with it than 2 stroke vs 4 stroke oil.
My last teardown being a case in point - really clean inside after using BP ultimate for the life of the engine with 4 stroke oil injected (+ 2 stroke premix)

Put it this way - I have not seen any evidence around here that cars running 2 stroke last longer .

Agreed that gas quality makes more difference.

Well since we are talking oil now I use 20w50 Full Synthetic

On stock leads ?
I have always maintained it's the leads that are the bigger issue than the coils .... Put good leads on there and your coils will last a LOT longer.

16) Keep revs below 4kRPM until oil is up to temp (5 minutes after temp gauge reads warm). I understand this is beneficial for two reasons:
First it avoids the high pressure bypass of the oil filter (safety measure for old/clogged filters).
Second, avoids excessive wear due to low lubrication levels of the rotors on the e-shaft side due to the e-shaft bypass valve being open while cold.

A SOHN adapter is not necessary to keep a Renesis healthy. What percentage of RX-8 in the world have them? For that matter, what percentage of RX-8 owners even know what a SOHN adapter is? No way on earth I'd buy a car that required a SOHN adapter in order to have a normal, long life. That's unacceptable to me, as it would be to 99% of potential buyers.

I think you got the impression wrong. I don't think it's required. I think that to obtain peak reliability chances, it should be used.


I fully expect that Mazda chose to inject crankcase oil rather than to have a separate 2-stroke reservoir for exactly the reasons you state. Customer PR trumps Engineers every time.

From all theories, myths and stories of things that are good for the rotary engine, I actually think the Sohn adapter is the one that makes the most sense.

In regards to the comments about "quality" gas, isn't that a little bit of another controversy?

Once at the 50k mark just because (car ran purrrfect).


Yep.

Motor is very strong, idles precisely @ 800rpm when warm, and I have no misfiring or predet at all.

By the way, just wanted to say I test drove a Lexus IS250 and IS350 recently (out of pure curiosity) and that while the IS350 pulled strong, I'd take the 8 any day over either.

I realize everyone has different tastes and needs, but I'll take the steering, chassis, torsional rigidity, and hydraulic clutch & stick in the 8 all day long.

By the way, there's as much useable rear leg room and head room in the 8, if not more so, too, the ride quality isn't any worse (I think it's better, personally) and the gauges and interior material quality is at least as good as in either Lexi, IMO.

My how the mighty have fallen.

I don't even have a desire to test drive the new BMW 3, fatty that it has become (with the only desirable motor, the inline 6, now optional, by the way).

There's not a single new Acura that interests me.

Here in NZ the is normal gas 95 octane , but you pay a premium for the 98octane 'ultimate' gas . The big hype with it is for cleaner burning :dunno:

gasoline is a hydroCARBON, so if you use gasoline there will be carbon in the engine.

i think this is right, the worse the connection between the coil and the plug, the harder the coil needs to work, and the shorter its life will be. i also wonder about the connection of the coil tower and the coil body..

+1, i think this is why we see torn down engines with bad bearings, there is some time period between when the water is up to temp, but the oil pressure is still low…

Sorry, I don't understand what you mean by "leads". Are you referring to grounding? If not, what can I search under to investigate this improvement?

Thx

"Leads" = "Plug wires"

Someone doesn't watch enough Top Gear :)

Been watching only reruns lately as I have been really tight on DVR Space:lol2:

I was thinking of leads meaning on the input side rather than the output, so mine are all upgraded already=peace of mind.