Hey.. ive been searching for the past hour for a picture comparison of the 2 piece versus the 3 piece seals, i remember seeing them not too long ago in a FSM-type thing that showed the updates on the seals, and from 1st-gen-2nd gen or something like that. All i realyl need is a basic pic of the 2 piece seals and 3 piece seals to prove a mechanic wrong... hes a dumbass ford guy haha. he thinks that the apex seals are one piece until the first time they are fired then break in to 2 piece to seal or something? i know hes smokin rocks but i just want to show him lol.

thanks in advance..

 

technically, he could be right. some people, myself included, glue the seals together before assembly. it helps keep the corner piece in place when you turn the front rotor down and keeps them from popping up when you're about to put the rear housing in place.

aside from that being the reason he said that they are one piece (or if he's seen the carbon seals) he's just a dumbass.

 

yea i guess he could be, but the way he said it he was pretty positive they were 1 piece, and he started going off how no one in canada can rebuild the motors except for one guy in calgary, and how u cant reuse the apex seals if u pull the motor apart, etc etc....

anyways, still looking for pics to help me prove him wrong.... i just want to show him the 2 diff types of seals, and how they function and everything... thanks.

 

http://rotaryengineillustrated.com/r...pex-seals.html

 

is it me, or did they mean to say "ceramic" instead of "carbon" seals? i thought boost is a surefire way to murder a carbon seal - not to mention, the cost they quoted.

 

Yea, that doesn't jive with what I've read. From my reading, Carbon seals are only for NA applications. Since they are generally 1 piece seals, the compression isn't as good as the multi-piece seals but the wear characteristics make them idea for race engines.

 

hmmm thanks mahjik but thats not really what im looking for... what i was actually looking for is the FSM-type kinda brochure thing that goes through all the updates from the 12A to the 13B i believe it was... It had a few pages on the changes of the apex seals, showing side views (side of rotor, so you would be looking down the length of the apex seal), it showed exactly what i want to show this mechanic.... someone plz help!!!

 

dude, i'm not getting something ...

if all you want to do is show that guy that the apex seals are not usually 1-piece, then how do the pics that Mahjik linked not useful? it shows 1-, 2-, and 3-piece seals - double spring and single. what do you need 12A and 13B for? only differences are 12A and older 13B springs are 1 mm wider. they have the same layout as the 2-piece seals with a single spring.

 

Hmm.. so what came from the factory regarding seals? did they used to use 3-piece and switch to 2? or have they always used 2 piece? hmm im confused now. this contradicts what i always use to believe...

Also can someone summarize the 3 types of seals (1 2 and 3 piece) with some cliffnotes? like what application, how strong, wear, etc...

 

my historical facts are limited, so i'll try to keep it to what i know.

engines up to 1985 were 2 piece, though i'm not sure about the 6 mm seals of old. the Gen II Rx-7 engines started with 3-piece seals in 1986 and i know they lasted through at least Series 4. i don't know about Series 5.

from what i was made to believe, though i may stand corrected, at some point Mazda went back to the 2-piece design and, thus, they are the only ones available now when you buy new apex seals.