Zero clearance side seals round 2. (If you don't mind Barry)

[Barry Bordes]

p
[QUOTE=RICE RACING;320079]There is some real dumb and wrong assumptions state above ^

The side seal is NOT constantly forced to one side!@ IF it were it would never wear a path into BOTH corner plugs as it does in reality!


Peter you are incorrect. Anyone who has disassembled a rotary has seen that you have blow-by on only one side of the corner seal. If you see wear on both sides you have set the side seal too tight and the corner seal may fail... (along with pinching the apex seals and adding high wear to the side plates)
You had problems in that area before with NRS corner seals... maybe that was the problem.

The rotor can only go one direction... and parts of it may sweep faster or slower, but all portions are always going forward... rethink your position.




A true ZERO BLOW BY design like I have made needs to be recessed into both corner plugs and not some ghetto cut off wheel doing a straight edge cut leaving a sharp edge too! that will not only seal like total crap but cause a very large stress raiser in the corner plugs = very poor idea.

If you look at the rotor path you will see the side seal rocks back and forth in the side seal groove on each minor dimension of the rotor housing points, thus it slams from one side to the other in the side seal groove! it needs to be recessed into BOTH, so not only is the clearance NOT zero as in the un thought out claims by others who have butchered this mod, but its also not the correct way to do this either as shown above.

Here is how its done right! below. This to work properly needs a bespoke material side seal and corner seal, as the stock parts are failure prone as is.
There is clearance to all parts! and needs to be done by not an engine builder wannabe but by toolmaker/fitter/turner who have precision parts fitting qualifications and experience, NOT GOOGLED!@
QUOTE]

[RETed]

Originally Posted by Barry Bordes

Peter you are incorrect. Anyone who has disassembled a rotary has seen that you have blow-by on only one side of the corner seal. If you see wear on both sides you have set the side seal too tight and the corner seal may fail... (along with pinching the apex seals and adding high wear to the side plates)
You had problems in that area before with NRS corner seals... maybe that was the problem.

The rotor can only go one direction... and parts of it may sweep faster or slower, but all portions are always going forward... rethink your position.

In a PERFECT environment, this is true...

You might find it surprising, and most of us live in reality...

Under less than ideal conditions, seals can resonate back and forth.
I.E. under pre-ignition and / or detonation

If you can guarantee that your engine will never see such conditions, then you would be right.


-Ted

[Barry Bordes]

Originally Posted by RETed

In a PERFECT environment, this is true...

You might find it surprising, and most of us live in reality...

Under less than ideal conditions, seals can resonate back and forth.
I.E. under pre-ignition and / or detonation

If you can guarantee that your engine will never see such conditions, then you would be right.


-Ted

Ted, I am a little surprised that you, as a moderator, would become an advocate for someone over the truth.

I was under the impression that you had disassembled many engines.....
Certainly you should have observed what is depicted below.

On the left side you see the wear from driven side seals... on the right observe that there is a ghost of wear ..... no wear whatsoever.

Barry

[RETed]

Originally Posted by Barry Bordes

Ted, I am a little surprised that you, as a moderator, would become an advocate for someone over the truth.

I was under the impression that you had disassembled many engines.....
Certainly you should have observed what is depicted below.

On the left side you see the wear from driven side seals... on the right observe that there is a ghost of wear ..... no wear whatsoever.

Barry

[URL=http://s287.photobucket.com/user/bbordes/media/EFR%20Manifold/engine%20pictures/IMG_11781_zpsbvhj0p2s.jpg.html][IMG]http://i287.photobucket.com/albums/ll129/bbordes/EFR%20Manifold/engine%20pictures/IMG_11781_zpsbvhj0p2s.jpg[IMG][URL]

Nah, I like the truth actually...

My conclusions are with discussions with someone with a Masters degree in Mechanical Engineering.

We blew up a 13B-REW with no turbo (long story) that only managed to put down 130 - 160hp at the wheels on a DynoJet.
The engine was running milled 3mm rotors with 3mm apex seals.
HOW DO YOU BLOW UP SOMETHING LIKE THAT?

The apex seals did not have chipped corners like most of your failed apex seals.
(You did tear down enough engines to observe this, right?)
The apex seals were cracked straight down the center - height-wise, of course.
I have never seen apex seal failure like this except for this one particular incident.
The mechanical engineer stated that this failure was a consistent with a harmonic oscillation failure of that type of material.

Why am I talking about apex seals when you're taking about side seals and corners seals?
You're smart enough to make that connection, right?

Oh, and just to back that up...
It's been documented by Mazda in a Mazda technical review used as reference for an SAE paper.
You're smart enough to go look that up too, right?

So, you posted a pic of just about 3 engine's worth of corner seals...
How about the other thousand you've come across in your experience?
Are you going to state that all the other thousands of corner seals look exactly like the ones in your pic?


-Ted

[Barry Bordes]

Originally Posted by RETed

Nah, I like the truth actually...

My conclusions are with discussions with someone with a Masters degree in Mechanical Engineering.

We blew up a 13B-REW with no turbo (long story) that only managed to put down 130 - 160hp at the wheels on a DynoJet.
The engine was running milled 3mm rotors with 3mm apex seals.
HOW DO YOU BLOW UP SOMETHING LIKE THAT?

The apex seals did not have chipped corners like most of your failed apex seals.
(You did tear down enough engines to observe this, right?)
The apex seals were cracked straight down the center - height-wise, of course.
I have never seen apex seal failure like this except for this one particular incident.
The mechanical engineer stated that this failure was a consistent with a harmonic oscillation failure of that type of material.

Why am I talking about apex seals when you're taking about side seals and corners seals?
You're smart enough to make that connection, right?

Oh, and just to back that up...
It's been documented by Mazda in a Mazda technical review used as reference for an SAE paper.
You're smart enough to go look that up too, right?

So, you posted a pic of just about 3 engine's worth of corner seals...
How about the other thousand you've come across in your experience?
Are you going to state that all the other thousands of corner seals look exactly like the ones in your pic?


-Ted

Ted... my guess would have been that there was an interference fit in the freshly milled 3mm slots causing the seal bind when heated.
That combined with the infamous peaks caused by the hot spark plug area caused the seal to break in the center.

Maybe we could add a #5... when installing all seals make sure that there is absolutely no interference and that the seals spring freely (per the manual).

By the way Ted if you have a reference please post it! It will only help the forum.

I also noticed that you have not provided any pictures of double worn corner seals. I actually have some but they are ones that I reversed from the last rebuild.

To be fair to your thought process... I might theorize that possibly on very hard decel... like at an autox that the seals might be slung forward... but I have not seem any evidence of it.

Barry