6mm apex seals?
 

y didnt mazda stick with 6mm apex seals?? i was reading on http://www.rotaryengineillustrated.c...pex-seals.html

im guessing for production cost right? cuz 6mm seals sound better than 2 mm. and a rotary would talk longer to break down. u think theres anyone that makes 6mm apex seals for a 13b or is that a bad idea?

the 6mm seals were in the original 10 and 12a engines iirc. bigger doesn't mean better... they had serious sealing issues which is why they used 6mm seals vs the mettallic 2mm seals we use today.

oh, and also the lifespan of those older motors was 1/4 of what it is today.

I do beleive that those had some serious issues with seals chattering on the housings.

Bigger isn't always better.

For example, my dads RX-2 died at around 30k miles, I think of a popped seal.

.. they y it said on the site the old motors lasted longer than the ones today?

so ya'll think its a bad idea? they couldve made a better design or fix all those problems

If you noticed as the rotary evolved the apex seals got smaller. The 2mm apex seals actually seal better.

hmm i thought itll be better cuz it was fucking fat ass seals but guess not =/

i have no idea why they would say those motors lasted longer than they do today, that is completely wrong.

they did make a better design, the 2mm seal...

What bout rounded 6MM? the top is rounded alitte?

iono idk how the seals exactly work, is it 6MM longer or taller?

so y does some people have 3mm seals? better than 2?

dey shud use da 9mm seelz frum da skyline gtrz!!!!!!

the old seals sucked, mazda has improved a lot.
The FC and up 2mm seals are the best

people are running over 650rwhp on stock 2mm mazda apex seals. that says a lot about OE parts.

damn si bet ur dad needed a new housing too that sux!

oo yea man i kno. theres nuttin better than the mazda oem seals. thats y when i rebuild mine imma get some oem ones

I honestly don't know, as I wouldn't be born for several years at that time. He bought it new, if that tells you the time frame.

FWIW, the 10A used 6mm seals.............but it was a factory P port engine.

The seals in a 13B are thicker than the renesis seals, we (the 13B) only have one peripherally oriented port, the Renesis has none. See a pattern here?

the original 6mm seals were carbon, if you are familiar with carbon you know it is the softest material ever to be used for apex seals and does not have a long life expectancy. they used the 6mm seals also to help aid in sealing but also because of the PPed housings, the motors still didn't last very long.

the 3mm seals were in later models, they worked and worked well but still caused some excessive rotor housing wear which is why they moved to 2mm seals to try and cut back on the wear and heat generation that the 3mm seals caused. 3mm seals also tend to wear out the rotor groove quicker because there is more mass that is trying to twist and move in that slot.

the 2mm seal was and is used for most of the highest performance engines built, they generate less heat and seal just as well. if there is a tuning error, a 3mm seal will help prevent the seal from breaking up but only marginally, it may save the motor but the life is decreased due to extra friction and wear.

the renesis seals are still 2mm but not as tall, because there is no vertical load on the seals since there is no port to pass over, they did get that one right so seal failure will probably be reduced yet again with the new design.

13b-mspre vs 13b is moot point, the mspre has a 2 piece seal, the 13b 3 piece seal is larger total but the individual seal parts are not, so it has no difference wrt bridging the peripheral port.


The larger seals have more mass, as the revs continued to increase the mass of the seal had to come down to prevent high rpm floating without having to go to such a spring tension that housing wear would be a problem or a seal material that was lighter but would wear quickly.

The renesis revs higher, it's missing part of the seal that was in the 13b.... you do the math.

I was under the impression that the Renesis used 1mm seals..?

10a didnt it have like 3 or 4 mm seals

Nope, still 2mm. They are shorter in height, though, for the reasons described above.

they also had 2 (like in two), 2mm seals, side by side, in one groove.

YUP! today best we know is the ceramic seals.

How old are you?


There was only a handful of factory 10aPP's ever made - but many thousands of 10a standard ports with 6mm carbon seals.

Many of the 10a's lived for 10 or more years... the seals were not the problem, they mostly had oil control issues - until they swapped to the later oil O rings (moved from the yellow to the green/black O rings). I have stripped many 10a's and almost all had mint rotor housings (carbon's don't wear the housings at all). The ones with over 100K miles have rotors with worn corner seal grooves (cranking speed compression starts to drop away), but you never see broken apex seals (even when pulling 9 or 10K rpm all day :) )

Mazda swapped to the 3mm then to 2mm as there is less friction - more efficient and responsive. I am sure that they would run 1mm if they could find a material strong and durable enough.

what does my age have to do with it?

point is how many 10A's with original apex seals have lasted upwards of 300k miles? i have seen a number of 12A and 13Bs do it without having been cracked open but not one 10A from other owners experience but that is probably because the engines are torn down for various reasons and rarely have a ton of miles put in them because of those issues.