Iluvrevs

FWIW I had a mechanical engineer and tribologist tell me today that with ceramics the rotary has a bright future as these will greatly reduce or eliminate carbon deposit issues and provide significant improvement in engine life. This was in reference to mating the rotary to a hybrid application. Not sure on anything more specific as I didn't ask.

nycgps

iTrader: (1)

stock Renesis E-shaft is not heat treated you say ?

shadycrew31

iTrader: (6)

It most likely is I just like saying it isn't to annoy people.

I do know that the lobes for each rotor see well over 500* due the bluing found on the e-shaft.

nycgps

iTrader: (1)

well, u get those bluing even when the shaft is new, I'm 99% sure all e-shaft were heat treated, otherwise they will "twist/bend" under heavy load. ,

and they start doing it sometime after 1978 I believe. correct me if wrong on it.

9krpmrx8

iTrader: (46)

My shaft is heat treated.

nycgps

iTrader: (1)

*which shaft are we talking about here? *

shadycrew31

iTrader: (6)

Nah I've seen plenty of low mileage/new eshafts none were blued, **** mine had 123k and didn't get blued till I slapped on the turbo.

sweatr

I have looked at several post on royal purple and I can't find the answer and the question is at what mileage would it be not recommended to start using royal purple because most of us are on a learning curve and we don't have the knowledge to begin when our ride is new, most of ushave varying mileage on our 8, I have 79,000 on my 8. I change oil every 2000 miles.

I am hung up on the comment about royal purple wiskeing away any deposits in the engine and could cause a leak. Any one have an opinion based on experience?. How many mile did you have on your 8 when you switched to royal purple?>

shadycrew31

iTrader: (6)

Its not the 80's anymore switching between synthetic and dino has little to no effect on orings. We have technology now.

sweatr

You are correct a mundo!. I just spoke with royal purple people and the politic is what is clouding the issue. I have made my choice. I am going to switch to royal purple and we shall see since I am very hands on with my 8. It isn't my daily driver, it's my version of a Harley.


"Don't park it where you can't see it" "3 moving parts makes for confusion"

ASH8

OK...your 'experience' is really enlightening..

This from someone who re-uses Rotor Housing when chrome is peeling off and says OCR's are not sold in pairs..(just having a laugh ).

And IMO Karak is very valid.

BEARINGS for the last time ARE the same for 13B and RENESIS, you are completely wrong again...they date back to 1991 for the high power, 1969-1990 for the 4 port Auto's and all other RE's.

I will deal with 6 ports so I wont confuse you.
All Renny 6 Ports..and 13B FD RX-7 WHEN NEW from Factory.
Rotor Bearings 2 x N3A2-11-B11 or 2 x N3A3-11-B11
Stationary Gear Bearings 2 x NF01-10-E04

Karack

ceramic apex seals have been used for decades with good success in certain rotary applications but i have never seen them used in side seal applications, because the ceramic would be so thin that it may become problematic with the brittleness of the material. shattering even a single side seal would render everything in that combustion chamber utterly useless for rebuilding.



the RX8 shaft is heat treated and hardened. it is slightly lighter than previous older model shafts. the dimensions are basically the same, which is also how many people have been able to use the renesis e-shaft in early 13B engines.

the rotating assembly weight has little bearing on anything we're talking about, if anything the lighter assembly puts less stress on the bearings which allows them to run lighter oils with less dramatic side effects.

shadycrew31

iTrader: (6)

Firstly, I used housings with minimal chrome flake because I was unemployed and needed a car. Fun fact that engine lasted me 3 years .

Secondly, I know that you love part numbers so I will throw some at you and let you research.

74-91 + RX8 4port main bearings Part number 0820-10-502 That is not the 6port...

6 port and FD part numbers are as follows

NF01-10-E04
NF01-10-E05
NF01-10-E06
NF01-10-E07
NF01-10-E08
NF01-10-E22
NF01-10-E23
NF01-10-E24
NF01-10-E25
NF01-10-E26

Most are shipped with the NF01-10-E04, however not all. Also there is no way to confirm that.

I cannot guarantee for certain but I highly doubt the reman plant is measuring for clearances and using the appropriate bearings. Most likely they press out the old press in the new and off she goes.

Also most builders are not measuring this and ordering appropriately. Shoot most people don't even know there are multiple bearings that can be used.

You got me on the rotor bearings though, I could have sworn they were different.

ASH8

You said that the RENESIS bearings were different to all other 13B's, you were incorrect.

You are just confirming what I originally said as I called you out , and listing what I have already said..

All the other 9 (RX-7 FD 1991) over-sized Stationary Gear Bearings are NEVER used, Why, well you should know this as an experienced re-builder.

And you are wrong again, Mazda never used these oversize Bearings in production, Why would they?

They are only for Re-builders as a replacement part, if the E-shaft is that bad it would be renewed with new (or should be) and you go back to Standard Bearings.

BTW:
I never said it was a 6 Port, as 0820-10-502B Bearings are the 1969-1990 (up to 1990 13B RX-7), and all earlier Rotaries, including 4 port Renesis RX-8 Auto.)

0820-10-502B are also used in R100, RX-2, RX-3, RX-4, RX-5, RX-7, 10A, 12A, 13B.

nycgps

iTrader: (1)

bearings, size wise (if it will fit) are all the same in 13B.

I just checked some papes, all E-shaft are heat treated

Renesis E-shaft has an extra "hole" to make it lighter, it does not effect rotating assembly all that much, both counter weight will "Fix" that (for most). it works even on high powered 13B-REW setups with no modifications. Thanks to better technology.

ken-x8

Why would anyone rebuilding an engine not measure clearances and know about replacement bearing sizes? Isn't that kind of rebuilding 101?

Or overhauling 101 if it's just using a .001, .002, etc., replacement without regrinding the journal.

Ken

shadycrew31

iTrader: (6)

Sir they are not the same.



When I said the bearings were not the same I referring to the 13B and 13B-t Engines. I never mentioned the REW, where do you think I got this info from in the first place (hint the REW)...

Back to my original point, you need to spec out the clearances and use the appropriate sized bearing for the E shaft being used. Since you were wondering that's why you would use an "oversized" bearing. Most builders re-use e-shafts, at least the ones I've talked to.

I never said that the factory would use different sized bearings, I just said there is no way to confirm that they don't ...

Also, Knowing that the reman facility uses housings with minimal chrome flake I highly doubt they spec out the bearings and use the proper ones. They most likely press in yellows and call it a day.

In any event the difference between each bearing is very small but I believe this adds to the issues we see with abnormal bearing wear.

As the e-shaft wears down a larger bearing needs to be pressed otherwise the tolerances will get too large. That is why they make the larger bearings, its not to add more text to the books. It actually serves a purpose.

shadycrew31

iTrader: (6)

You'd be surprised sir...

ASH8

You are just being a s-a....by pulling out my 'quotes' out of context.

A RENNY is a 13B!!, your 13B-t I guess means FC TURBO, well say so?...who cares.

Where I said bearings are the same I was talking in context to all 13B's IN FD's and you know that as I said 1991 (not MY), which are the same, both Rotor and SG Bearings to the Renny 6 port.

As for E-Shafts...in 30 years of Mazda parts supply we (I) never sold OS Bearings for RE's, even if they are available, they are just dead stock, a new or unmarked E-shaft is always the best option...and yes is re-used, if it is not marked, therefore worn, then standard size Bearings will always be supplied and used...I have never had them come back as wrong.

It is also a complete waste of time to ''machine'' journals and fit OS, again because of cost, practicality and e-shaft durability.

Now on to a US Reman facility?,
I guess Mazda Virginia?,
I have never heard them talk about re-using Rotor Housings with chrome flaking off as any flake off is not what MMC Japan ever recommends.
Also I was not aware they were pressing in Bearings at all, last I heard from an insider/worker/employee they throw out SG (complete) and Rotors and use brand new Rotors and S Gears with bearings pre-installed in Japan...I thought you knew that.

Perhaps this could be, perhaps why so many renny's have failed in USA after a few months of owner use as they (Mazda Virginia Re-man) are not doing it right by re-using old rotor housings and pressing in new bearings....last I heard they were not capable of pressing anything much in without fecking it up.

Personally throwing away perfectly good Rotors and Stationary Gears because of worn Bearings is just a waste, they (Mazda Virgina Reman) should learn to clean Rotors and reuse (where they can) and correctly press in new Rotors and SG Bearings??.

If done correctly to save cost this IMO is a better idea than attempting to use flaky Rotor Housings which are already defective beyond repair.

Karack

so mazda had the foresight to introduce oversize bearings almost 40 years later to save e-shafts(which are cheap enough anyways compared to machining them to oversize).

does that mean that the standard brand new engine you get with your car has oversize bearings? i certainly hope not.. the bearings and tolerances are still the same as they have always been, even on the older engines except you now have more options(which actually aids the older engines more than the renesis which has new shafts available versus say the new old stock 12A which in time may be cheaper to salvage an e-shaft but still even to this day good e-shafts far outnumber the other worn engine components).

ASH8

Agree...spot on..

ltlacour

Oh boy, hot topic.
I ran Royal Purple in my turbo 13B Rx-7 with about 300whp.
20/50 in the crankcase and their 2-cycle oil in the tank.
No metering pump, pre-mix only. Mixed it at 16 ounces per tankful, usually 13-14 gallons, sometimes as few as 10-11 gallons.
Prior to switching to the Royal Purple, I ran Castrol GTX in the crankcase, and Yamalube R in the tank at the same basic mix ratio.
The huge differences were the engine operating temperature, and the smoke from the exhaust.
The Royal Purple reduced the engine temp by about 10 degrees under sever conditions, like going uphill under boost on a hot day. I never saw the 200 degree mark with the Royal Purple, but frequently with the GTX/Yamalube.
Also, the exhaust smoke with the Royal Purple 2-cycle oil in the tank was greatly reduced. This was also evident when pulling the spark plugs.
I haven't put Royal Purple in the Rx-8 yet, because it is all stock and it is driven reasonably in most cases. But I have considered putting a small about in the fuel tank as insurance against metering pump failure.

sweatr

It's not as much a hot topic as it is a prime example of how mankind can't agree on any thing as well as our stead fast desire to be right ,as if it were a bone a dog gaurds.

My thought is if you don't like royal purple or any other syn.....Well then don't use it,geeeeeeezs man. I have researched the issue including the often skipped part of the political end of factory recommends etc and my finding is I choose to use syn oil in my oil sump and my differential and transmission. If some thing fails, so what , **** breaks.

Most of the arguing and posturing that goes with this subject of syn vs conventional oil here on this forum is because, there is no oil god and many haven't bothered to look at the political reasons Ford controlled Mazda in this country the USA.

At the end of the day , either use it or don't , but at least do a little research and I don't mean here on this site. It is an informed decision in my book. I'm using Royal Purple for my own reasons( research that satisfy me.

Ever do any heat rap?. Another sticky I know>

ASH8

Members...I have tentative permission to make available here (ONLY) the genuine Mazda (Japan) RENESIS 13B ENGINE (Series I and II) Workshop Repair Manual made available to members (which had to be split because of size).

https://www.rx8club.com/series-ii-te...0/#post4462850

Note how Mazda Japan calls their engine a 13B-MSP

ASH8

Interesting to also note from the factory RX-8 Engine WSM that 95% of the Mazda Special Tools for engine repairs that Mazda suggest ‘should be' used are many, many decades old.

Particularly the 49-0813, 0839 and 0107, these are 1968, 1969-71 and 1965 originally made and used, for all 10A and 12A, and still to this day for the Renesis.

None of these tools are specific for only Renesis engines, a few other tools are from FD RX-7

In other words the ....
Fly Wheel Wrench (1968) all rotaries,
Counterweight Puller from 1970 12A RX-2,
Seal Case, Dowel and Oil Pump Puller also 1970 12 RX-2,
Oil Control Ring Seal Remover 1969 10A R100,
Stationary Gear (Main Bearing) Puller and Installer 1969 10A R100,
Rotor Bearing Puller and Installer from 1969 10A R100,
Corner Seal Cleaner and Clearance/Depth Gauge from 1970-71 RX-2 12A.

Nothing has changed much in the past 40+ years, even with the 13B RX-8.