scathcart

Ignoring the comment on a reputable rotary shop or an engineer?

Why has Mazda installed one in every rotary they have ever produced if it is not required or beneficial?

How many miles have you logged running without one?

What method are you using to measure and conpare wear?

Sometimes you should step back and realize the people that design and test a vehicle for reliability are a better source of information than a backyard mechanic with self anecdotal "evidence".

"Half the bolts holding down the seat are pointless! I left 2 of the 4 off and have never had a problem".

Acesanugal

iTrader: (5)

Fight the misinformation my brethren, fight to the death!

insightful

the engineers at mazda also used 3 piece seals, we know how well they work...

we can argue engineering degrees if you want, and how they also don't always work out as well as that argument works either. so what will be your next comparison here? the rotary engine itself is an engineering marvel and also horrendous engineering failure. every series of rotary engine has inherent flaws, designed by engineers who spent countless hours doing engineering things.

thing is, the seals were put in by factories with transmission alignment dowels, things most common people do not have.

professionalpyroman

Welp,

after a long day of engineering, thinking about engineering things, and talking with the wife about her daily engineering, it is time to retreat to my favorite forum about rx7s.

I may go out to the shop and make me up a set of those alignment dowels. Probably about $10 worth of steel, $0.15 worth of cutting oil, and $6 worth of beer. All of these items can be found pretty much anywhere. Lathe work will make fancy parts, but a vice, rod-stock, hacksaw, and the right thread die would be all you need. If they work well, might sell em.

Engineers fix problems. Can't keep oil in something? Put a seal on it. Just rebuilt a grinding machine for my shop, over 100 years old, still had the original leather bearing seals in it. Ball bearings were in perfect condition, repacked with grease and resealed. Hopefully last for another 100 years. The only way to get quality tools in your 20's is to fix old ones. BTW, the newest thing in my shop is the RX7...

We have 2 methods here: use the seal or don't. One of these has a built in safety factor (an engineering term for likely-hood of failure), and the other has a pucker factor (another engineering term for likely-hood of failure). Strangely enough, both are mathematical inverses of each other. When the safety factor drops below 1, it becomes pucker factor, and vice versa. Too high of a pucker factor usually has equipment operators taking small circular chunks out of the seats of their equipment. These small chunks are then compressed into either coal or diamond based on the particular pucker factor at the time. When doing not only calculations, but operations, safety factor is usually the one to go with.

That's my $0.02, and it's late. Good luck folks

insightful

problem is, the aforementioned dowels are very difficult to work with while the engine is in the car. the alignment procedure from the factory is all done with the engine and transmission out and on a workstand.

but lets be real for a minute, you aren't going to make dowels to align the transmission, you just want to be correct here. the proponents in this thread don't want to back down to some random idiot with 20 some posts. nor was it really my intent to put anyone down, even though a number have been to me.

scathcart

They did work, as proven by by SAE papers. What's your point? Mazda abandoned them for an inferior sealing joint in favour of a longer lasting seal for turbo engines. The engineering was tested And solid, as proven by the many 200K mile NA engines.

ok, lemme know when you want to start.
You can start by answering my questions instead of just ignoring them.

Here is the issue: you are claiming an engineering design failure, spanning across every vehicle ever made, with zero proof other than: I left mine out and it gud, man.
Post some results. Do some long term testkng. Until then, its just a nescient opinion based upon zero testing that contradicts the professionals that have done so.


Funny, every Mazda race engine, including the 787B was hand fitted without machinery to their transmission/transaxle, and suffered no failures in the most gruelling of tests... like Lemans.

You're not even debating a rotary specific issue; everry Manufacturer uses a seal or a sealed bearing: you're telling me that every single automotive manufacturer on the planet is wrong... and you are right?

guessing you voted trump; you seem to endorse "alternative facts"

Acesanugal

iTrader: (5)

It's not that we want to be correct. We *are* correct. *you* don't want to be wrong.

And that's fine.. You're new here and are probably a bit embarrassed that several of us came down hard on you. However, there is no place here for misinformation. It's been a problem historically and it can be detrimental to others. It does happen, even to experienced enthusiasts - your memory can fail you - but it needs to be corrected.

professionalpyroman

I sure am going to make some. Gonna put a new clutch and synchros in the car and it'll be a good test for the dowels. I'll post them on a separate thread when they're done.

insightful

no proof? ok here

3 piece seals wear failure mode= total destruction. proof, we've all seen engines that could have lasted 300k miles that blew up at 120-200k, and instead of just resulting in low compression you got blown rotors, housings, turbos, irons, etc.


1968-1973 carbon seal engines= short longevity and could not handle even short preignition events without requiring a full rebuild

1974-1985 engines = chrome peel due to heavy 3mm iron seals

1986-2002 engines = failures due to inferior 3 piece seals for "beneficial sealing" and thin coolant seal wall castings that caused premature coolant seal failures

2004-2008 = engines have an 'average' lifespan of 90k miles due to latent heat burning side seals, inferior apex seal lubrication caused rotor housing wear and subsequent loss of compression to the point of flooding and required rotor housings to be replaced at a meager 100k mile figure.

2009-2011 = added oil injectors to bump up engine life about 25%, still not a great improvement.




i'm not sure why you think i haven't given any proof, i've given proof why the pilot seal can be a hindrance instead of a benefit.

is there a question there or are you trying to imply that people who voted for trump are dumb? personally i think that anyone who voted for EITHER of them was wrong, which is why i didn't vote, however you really should get off that horse before you fall off it.

insightful

does it sound like i'm new to rotary engines?

maybe i'm the one trying to correct some misinformation and actually a little disappointed. i also did not say you cannot use the pilot seal, i said perhaps you should not, and actually it was just a suggestion that has now turned into several pages of bickering and people calling me names and that i'm spreading misinformation.

the only reason i even come back is because now i feel like actually correcting the slander that people are flinging around.

scathcart

The difference here is Mazda tested this stuff. You haven't. Engineering is about compromise. The 3 piece seals sacrificed engine lifespan for improved combustion chamber sealing.

You're still ignoring all of my questions.

No one here has called you any names; you can stop filing your hurt feelings report. We're pointing out that what you are recommending is a terrible suggestion.

Again, find me a reputable shop, engineer, or automotive manufacturer to support your claim, or come up with some accurate measured data over several thousand miles on multiple vehicles.

insightful

actually i already gave those, so maybe i'm not the one ignoring but maybe it's you that is.

scathcart

Really?

One reputable shop?
One Engineer?
One automotive manufacturer?

Any empirical data from long term testing?

Nope. None of it.

Acesanugal

iTrader: (5)

I mean, at this point, I feel like we've avoided any newcomer being misinformed. There's enough of an argument that has gone on to convince just about anyone that the seal is required.

scathcart

The only "proof" you've given in regards to leaving the seal out is thus:
"if you screw up your engine install, you should leave the seal out."
Good argument.

No proof of longevity or grease fling.

No testing.

Just an opinion, and quoting failure modes of an engine (unrelated to thread topic) and trying to equate it to why a mechanic knows better than an engineer.

Answer me this: why hasn't there been a SINGLE aftermarket apex seal that is able to provide the longevity of a stock seal, including the 3 piece seals?
They either all wear out the housings or wear out the seal in short order.
+1 for engineered R&D versus backyard mechanics

insightful

this is just getting stupid. and mazda doesn't sell 3 piece seals anymore, they only sell 2 piece seals for the same engines that they originally built with 3 pieces.

scathcart

Still can't answer my questions...

insightful

you're like a broken record that keeps repeating, even when answers were given.

you haven't actually addressed why engineering actually sometimes fails, in regard to my examples.

Acesanugal

iTrader: (5)

You're just avoiding the truth of the matter, which is that the dust seal for the pilot bearing is needed.

lastphaseofthis

iTrader: (8)

they make a newer pilot bearing that has the seal integrated it the metal sleeve, can't remember what car i found it it, maybe mazda 3? or maita.
anyways you install the pilot bearing and the seal is dont for you making it a much less pita.

Acesanugal

iTrader: (5)

I still don't see where this idea comes from that installing the bearing and it's seal is some gargantuan feat. You just use an appropriate socket, a small extension and a hammer. I dunno, maybe I was just taught right... BY AN ENGINEER

And again, I get that sometimes getting the transmission to seat into place is a pain, but how are people damaging their bearings and seals?

This isn't witchcraft. Is it ?

Stop butchering things, folks.

insightful

needed is a point of view, as i said before not much dust gets into the seal because the inertia of the rotational mass does move everything from the center outward. you can typically see that almost all the dust collects in the shell of the pressure plate and in the bellhousing while the pilot area has almost none.


and now its considered butchery? lol, really... i actually find the counterarguments lacking, yet you guys are saying i am giving no supporting evidence for my side, and that engineering always trumps some everyday joe. problem is, engineering is sometimes flawed, needs revision, or is designed to cover lots of scenarios where most of them are irrelevant.

actually i think i'll continue to argue my side until someone gives ME a reason why my idea is a bad one besides saying 'it's a seal, it needs to be there'. well, it's not a boat, the pilot bearing isn't under water, so i still do not see why it NEEDS to be there. the main issue i have with the seal in this particular case is that it wasn't designed very well and tends to catch the snout of the transmission far too easily.


maybe you guys are being a little bit too biased, i know i can be that way too sometimes. when someone starts yelling for facts, when facts were already given then they are grasping at straws but don't want to back down even though they know there is potential legitimacy to the other perspective.

Acesanugal

iTrader: (5)

Bud, you can do whatever you please with your car, but it is not acceptable to misinform others with bad information based on your small opinion.

The pilot bearing seal is required for the proper operation and life expectancy of the bearing itself as per the engineering of the vehicle by mazda.
You have no way of proving that your views on the matter are correct, whereas mazda and essentially every other manufacturer out there has proved the validity of the seal with their use of it in the first place. Do you really think they would waste their money installing it if it was not required? No.
You are not an engineer backed by many millions of dollars of equipment and research and development.

There is quite literally nothing further to discuss.


/thread

scathcart

still waiting...

insightful

i'm waiting for the validity from your perspectives instead, but perhaps you have given up on trying?

i've given my explanations but heard nothing but basic reasoning that it exists for yours. actually i think i've proven more that it can be harmful than you have proven it's benefit. yet i still have never said that installing it was the absolute wrong approach, merely that omitting it is one way of avoiding a common potential issue. so actually you've given me no reason to budge on my own opinion.

everything has pros and cons and its up to everyone to decide their own direction.