rotaryPilot

So Paul what is the recommendation about switching to synthetic oil.

Can I switch to full synthetic ? My engine has 17.000 miles and 1 year of operation. Or is it too late?

nycgps

iTrader: (1)

you cant say its too late.

but keep one thing in mind --- Synthetic oil is not magic, it cannot undo damages.

rotaryPilot

I am premixing also with Saber Pro despite the fact that I am using 5W-30 Mazda Dexelia Oil

csl

On the stationary gear uneven wears, is it any possibility caused by the engine balancing?

Mazmart

iTrader: (12)

If you're referring to the bearings: No. We see this in a lot of stock renesis engines we take apart and not in the race versions that are running thicker vicosity oil. It's more related to alignment and oil film. The stock renny is well balanced.

Paul.

archiei40

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Mazmart

iTrader: (12)

I think you're quite safe at 17k to switch to syn.

Paul.

rotarygod

I actually want people to take note of this post. The reason being I've seen people blaming Royal Purple for issues and then saying to use Redline instead. This post shows that there is more to it than oil brand and that even the holy, sacred, God of all that is oil (in some people's eyes) Redline is not immune to problems.

Paul does bring up a good point though about switching vs not switching to synthetics. If a synthetic oil is better (I won't argue that) and you are using it from the beginning, or at least before any seal degredation and buildup occur, then your seals should stay cleaner and better conditioned during the motors life. If you use a conventional oil, and obviously quality differs from brand to brand, and your seals don't stay as well conditioned and gunk does build up which is helping them to seal, then switching to an oil later that will help clean gunk off can really only lead to nice clean seals that already have damage done to them. Damage that was being bandaided by gunk buildup.

I bought my '90 RX-7 at the end of January with 120,000 miles on it but I've actually left it with conventional oil in it although I've always sworn by Royal Purple and run it in my other cars (that I've owned since day 1). I've really only left it with conventional in it because I don't know how it was treated over it's life and with that many miles on it I figure what's done is done and I can't change it anyways. In truth I've actually never thought about any issues with switching later but if Paul is seeing results based on people who have done this then there's little room to argue with it. Result are results and I trust Paul and Rick more than I trust my own mother! Don't tell her that though!

I will say that based on the other thread about oil weight, since I am crazy and always seem to have a spare motor somewhere, I tried 1 oil change in my RX-7 using 5W20 to see if I could feel a difference. I still have plenty of oil pressure. The car did seem to run pretty smooth and mileage might have improved by a half an mpg or so. I'm pretty consistent but either way it's not much if there was even a benefit. However one thing I did notice is that after about 1200 miles or so, the smoothness has tapered off quite a bit. The mileage hasn't changed but now I've got concerns over whether or not I'm doing harm to the bearings and gears. I am probably going to change the oil out this weekend and for curiosity sake I'm going to send it over to Blackstone labs for a used oil analysis. I'll post the results when I get them.

stanknasty56

so i read this thread and i must say it was a good read but i do have a question for paul or anyother one that can answer it, i have been reading alot on here(not much else to do in iraq thanks to the sofa agrement)
i was thinking about switching to synthetic but after reading the last 2 pages i was wanting to know what you think it is safe to switch from dino to synthetic?? i have around 40,000 miles on my car do you think that it would be too late for me to switch?? thanks

9krpmrx8

iTrader: (46)

I wouldn't change at 40k but really there is no way to accurately answer your question.

d j

that's about the same time I switched from dino to syn. I've started with Idemitsu and then later on switched to Royal Purple. I'm almost at 80K and no issues so far. I've experimented with different weights as well. started with 5W30 and 10W30 and now I'm using 10W40.

btw, I just got back from Balad/Al Asad/Speicher/Kirkuk/Mosul/Tall Afar and Q West a few months ago. Stay safe!

robrecht

I'm old enough to remember discussions about synthetic oil from the beginning. As I recall, it was a common belief way back then that one should not switch from dino to synthetic on high mileage cars because of this issue, but as time went on this was relegated to old wives tale status. But it was an old wives tale that I continued to believe because no matter how many experts debunked it, I would continue to hear anecdotal reports of this happening. So I just kept on believing it because I'm sort of dense that way. Now I'm on the cutting edge again, woo hoo! So, rg, you can believe Paul and Rick AND your own mother on this one.

mafia910

I've read all the posts in this thread, and I'm still left with a question:

If I live in a 4 season state (Maryland), what oil should I really get. It seems 5W-20 is definitely out, but there seems to be some discrepancy between if I should use 5W-30 and 10W-40 (the two most recommended).

If someone could clear this up for me, that would be great!

ASH8

/\ Personally I would go for the latter, particularly if you renew your oil only at the scheduled service intervals...

Sorry, I know I will make someones blood boil, but I am just not a fan of 0W or 5W anything in a rotary,...,but that is just me and a few other oldies and engine re-builders.

nycgps

iTrader: (1)

I live in NYC, Im not that far off from Maryland, I get 4 seasons.

I use Full synthetic 20w50

mac11

iTrader: (1)

has anyone ever considered a different oil for the different seasons? 0/5w-30 in the winter and 5/10w-40 in the warmer months?

nycgps

iTrader: (1)

a lot of people do that.

I "used" to do something like that, but Im gonna give 20w50 a shot this winter. I mean I use "real" synthetic, it wont freeze or slow down that much even at 20f. so Im good.

mac11

iTrader: (1)

where is the proof of that?

TYPICAL PHYSICAL PROPERTIES

AMSOIL High Performance Synthetic 20W-50 Motor Oil (ARO)

Kinematic Viscosity @ 100°C, cSt (ASTM D-445): 18.9

Kinematic Viscosity @ 40°C, cSt (ASTM D-445): 123.8

Viscosity Index (ASTM D-2270): 172

CCS Viscosity @ -15°C, cP (ASTM D-5293): 3525 (-15)

Pour Point °C (°F) (ASTM D 97): -36 (-33)

----------------------------------------------------------------------------------------

TYPICAL TECHNICAL PROPERTIES
AMSOIL XL 5W-30 SYNTHETIC MOTOR OIL

Kinematic Viscosity @ 100°C, cSt (ASTM D-445): 10.5

Kinematic Viscosity @ 40°C, cSt (ASTM D-445): 58.2

Viscosity Index (ASTM D-2270): 173

CCS Viscosity, cP @ (°C) (ASTM D-5293): 4341 (-30)

Pour Point °C (°F) (ASTM D-97): -43 (-45)



In the AMSoil 20w50 there is a HUGE jump in viscosity just between 100*C and 40*C. I would hate to see what that number is like at 0*C and think about startup conditions. The cold viscosity (40*C) in the 5w-30 is drastically lower. And you can see the pour point is higher on the 20w, more proof that is does thicken up and slow down in colder temps more quickly.

I just don't understand why everyone always tries to apply one blanket solution for drastically different conditions.

mafia910

That's a good point mac11. Maybe I should go 5W-30 in the winter and 10W-40 in summer. Anyone think that's a bad idea?

RX8.PIPE.DREAMS

iTrader: (1)

This thread has some wonderful information about oil usage but I feel there is one area that hasn't been touch on too much Paul. Once again thank yo for the many explanations, but besides mentioning that premix is good for the engine, can you touch base on how much is the perceived "ideal amount is?" I know many people including myself are running 4 oz per tank (around ~13 gal. fill-ups). Just want to know your thoughts about premix in general. Thanks.

-Chris

nycgps

iTrader: (1)

Because the so called solution really worked for more than a decade. Just go ask any rx7 owners. They will laugh at ur ***.

We can argue this all day. But the hard proof here is the engine wear. Maybe if you can show me something with no noticeable wear. Then we will talk again

Andd the different season with different oil thing. Imo, its just a waste of time.

Just use one oil for all year long.

peterlemonjello

To premix or not is a huge debate let alone quantity. I doubt any amount less than 6 oz per tank is going to do much. I personally premix 8 oz of Idemitsu per tank with a functioning OMP.

Mazmart

iTrader: (12)

Hey Chris,

First I'd like to point out that I made a comment regarding Expo's pre-mix amount to which I don't presently hold. I don't blame his carbon build up on that but rather a/f ratios in conjunction with other factors of design.

We have run 1oz/Gallon (Pre-mix/Petroleum) in the past on our race cars and are experimenting with 2oz/Gallon of Red Line 2 stroke Pre-mix (Synthetic). Keep in mind that our race cars do not have the oil metering system at all. When on the street, we (The discerning RX8 enthusiat) add a pre-mix lubricant, we are supplementing an existing system. For that reason, I'm not sure that we need to run more than .5oz/Gallon on the street and of course some people's cars seem to use more oil in metering than others with variables that include driving style amongst other things.

I hope that's halfway helpful.

Paul.

Mazmart

iTrader: (12)

That sounds quite good.

Paul.

bose

iTrader: (5)

I just got a warranty engine and I am wondering if I should wait to switch to synthetic until it's broken in, or should I make the switch right away?