Why doesn't somebody make a one piece apex seal.

What does everybody use to glue the two apex seal pieces together?

I rebuilt a S4 NA a couple of years ago now and I absolutely can't remember gluing the two apex seals pieces together. Maybe I didn't.


ashley

 

you dont glue it. you just put it in as the last peice before you put the iron on. the iron holds it in place.

wait, you are talking about the triangle, right? if you talking about the split (like the old 3 piece seals) then you just stick them in and the housing holds them to the rotor.

 

super glue!

 

had the same thought about that. i dont know really. maybe someone needs to go yell at mazda. i feel pretty positive that that side piece was made so the springs could slide in more easily but last i remember doesnt look too hard to slide them in even if they were one piece.

 

Two words: thermal expansion.

 

^haha jolly good point

 

maybe if we can get a vet to chime in and correct our thoughts. I'm not terribly sure. I just thought that scientifically, the space that the apex comes in contact with the irons, when the motor was warm the apex seal would gouge the irons....I have an N/A apart, and i haven't been able to set it all together and see. I suppose the corner seal protects from this, but IDK to be honest. Maybe the seal is shorter, but there is still a tab on the triangle piece that would most certainly cause problems. /shrug. I am still learning.

 

there is one piece seals. super glue the ends. mazda used to make an assitst piece that stuck to the bottom of the apex seal and kept pressure off of the triangular piece. when the engine was started the assist piece melted and put pressure on the triangular piece.

 

sounds alot like the rubber piece in the corner seal that melts after so long.

 

well, like i said, the iron, housing, and rotor hold the seals in together. im still not sure if you guys are talking about the triangle piece, but that doesnt go anywhere once the engine is assembled. just take one apart and look at it. then, when you put it back together, youll see what i mean.

 

i thought they made one peice apex seals and they use them in full bridge port motors.

 

They do make one-piece apex seals, but they are NOT made for street use.
Multi-piece seals have the advantage of better engine sealing, so the engine runs better at low RPM's.
Once piece seals might be stronger, but their low RPM sealing SUCKS.
(Detonation typical "chips" the corners, so I doubt the one-piece apex seal is even worth the hassle.)
This is why Mazda does not use a one-piece seal for production motors.


-Ted

 

People seem to be very confused about why the seals are glued together.

The glue is simply there to make the engine easier to assemble. Glued seals mean that it's a lot easier to slide in the spring, and there's no chance of part of the seal falling out during assembly. The glue breaks the first time the engine is rotated.

This is less of a problem now that Mazda stopped with those damn 3 piece seals, but the corners can still be a pain if you need to reverse the seal direction and don't have direct access to the corner.

I've been told by a Mazda engineer that the rubber plugs were designed to prevent chatter.

 

I was just watching the atkins rotary video and david atkins didn't even put the triangle piece in place until he was ready to install the rotor in the housing. So I guess it doesn't HAVE to be glued.

 

I think the rotary training manual (NOT the FSM) has a picture and description that shows the part about the two long seals. I think you can get it via the links in my sig.

edit: use the second link for the FC training manual.

 

I have some recent experience with this, with one piece 3mm NRS seals in a huge street port 13b-rew, on just broken in (less than 2000 miles) housings we saw 105 PSI warm cranking compression. The NRS seals where new and had been run for only 20 minutes.

Just prior to disassembly and after tuning with 2mm 2pc hurley seals there was 115 PSI warm cranking compression.

The car, which is not very street able for reasons other than the motor was not noticeably different.

It was making near 500 WHP, on a 35R

 

Stock Mazda OEM 2-piece seals are about $50 - $60 each, or around $300 - $350 for a set of 6.
I think those racing 1-piece seals are even cheaper.

How much for those NRS seals?


-Ted

 

They normally retail around 1200, this set was purchased during a group buy about a year ago.

This is not my car, all I did was install the haltech and some other easy work.

 

Hey Ted, did you get my pm?

 

No it doesnt have to be glued but it does make it easier to work with when the corner piece is glued.