if i take apart my engine to rebuild it, and the apex seals and springs look like their in pefect condition, do have to replace them? money savings is the goal here. ALSO i can have my dad test them (ultrasonic test) which tests the metal for microscopic cracks. what are those seals made of anyway?

 

you dont HAVE to replace the seals but it is a REAL good idea... atkins seals are only $250 and there some of the strongest seals out there...

 

Measure the seals and check them against the specs. But hell if you can get em tested that would be cool, post the results up here I'd love to see! ALso give us the mileage of the engine as well.... but do the tests even if you do replace them!

 

How many miles? I would also recommend new apex seals. I am also doing a rebuild of sorts. Mine is lower mileage rebuilt engine that had carbon lock. Found the rotor housings were getting worn out. I am going to reuse my apex seals since they are almost new. Depending on how long you want the rebuild to last, here is somethings to consider:

rotor kit (apex seals, springs, oil seals, etc.) Atkins has them for $440 on ebay

gasket set atkins has them on ebay ~$80 12A, ~$110 for 13b NA

front and rear main seal ~$10 for both (mazdatrix, atkins)

pilot seal etc.

You may also want to consider rotor housings ~$750 new for the pair, Flywheel resurfaced, side housings lapped, etc.

It all adds up fast. Just depends on how much money you have and how long you want it to last.

Good Luck!

 

what about CF apex seals , i know they are for operating above 8500 RPM but if you dont go that high will they last longer?

 

From what I know, carbon apex seals usually don't last too long and are more of a racing thing. I remember that mazdatrix does recommend them for some of the bigger ports but they don't do well with boost. Ceramic is good for high temperatures, but is very expensive and they can still break. Your best bet is to stick with steel. Atkins have some that are a good design. The OEM ones are also good.

 

Hell, test the new ones and post results to compare .

~T.J.

 

Oh and I forgot to tell you my 2 cents...

I figure, if youre already in there, why not do it "right"?

~T.J.

 

If you've got the engine apart to replace an oil or coolant seal and aren't looking to do a full-blown rebuild, then I would check the steel apex seals and if they are still within tolerance, re use them. BUT, RMD has a point, if you've gone through all the trouble of taking the engine apart, you might as well replace the apex seals and not have to worry about them for a while.

 

REPLACE EM! thats the same thing i thought when doing my rebuild!! and because the full set of apex seals would have cost me $500AU i thought no way! my ones here look good!

so i went about building my engine only to find out that the apex seals wernt good, the engine had about NO compresion and i had to go spend $1200AU on a new motor..

they might look good but they create a VERY SMALL hole in the middle of the apex seal were it touches the housing..



to see how bad urs are, u can hold the apex seal hard up against the housing wall, just as it were it in operation and hold a torch behind it, if light seeps thru then it aint good. all u could sand the top back using some 1200 grit wet and dry paper to get them flat agian

 

a buddy of mine has a right done 13b carbed racing tranny ect..., its rated at about 274-278 HP... at the fly, it revs to 13k without riskin blowin the engine sky high..., anyway i was just wondering if anyone can make a guestimate on how much life it will have, its brand new with under 1000kms on it, here are the mods.

carbon fiber apex seals
heat treated stationary gears
holley 650 DP, 4bbl
racing beat intake
racing beat headers
super trap racing exhaust
msd ignition
fuel pump(forgot who made it)
i believe the rotors and housings are brand knew
im prety sure its a extended port or a very large street port because the revs bellow 3k are prety week, just wanting to know if anyone knows what kind of lifespan this would have because i might be buyin it some time this year and i dont wanna buy a old almost gone racing engine... oh ya it is being street drivin. there are some more mods i am quite sure but those are what i know he has.

 

the engine has 170,000miles on it. good oil changes etc.. great compression, redlines without a problem, and at 7k has 85psi oil pressure. The "testing" i could do, would test for INSANILLY small cracks, a matter of fact almost all metal has some sort of crack in it. my MAIN question now is, why the hell are these things so danm expensive, hell if get some solid high compression stainless steel and cut to exact measurements, could i use it? (not that i would, but why not?)

 

So damn expenisve??? $250 with rotor kit all the seals and everything you need for the rotors isnt expensive... apex seals are ALOT more then just cutting them to a specific shape with steal... ask the people the desined the 1st rotary cars... BELEAVE ME... its worth the $250 for some of the strongest seals out there with a rotor kit...

 

Actually, if you could get a new apex seal and have it analyzed to find out how much of what chemicals are in the steel and if and how much it's hardened, I don't really see any reason you couldn't buy the same kind of steel and have it cut down to an apex seal. I mean, metal is metal. Just make sure it's identical to whatever is in there...

--Danny

 

That’s a good point but you would have to find the same kind of steal... Get it made and cut IDENICAL to the other seal... end up spending ALOT more money then its worth... not to mention you couldn’t sell them... if the rotary shop you copied off of found out you would be FUNKED

 

Actually, I'd be willing to wager I could have PLENTY of apex seals made for way, WAY less than what any other rotary shop is selling them for. All I'd need to know is what they're made of, or a suitable replacement material and I could have 'em in less than two weeks. And, as far as selling them to other people, unless say Atkins or Mazdatrix has a patent for their own "special" apex seals, I could make 'em and sell 'em as I wanted to. No patent = free game. Look at jimlab's infamous "Unobtanium" bushings. They're nylon replacements to the stockers. Is jimlab the only one selling replcement nylon/delrin bushings? No.. again, no patent means anyone can sell their own version..

 

Well if you could make up some seals I'm sure I as well many others would be interested!

 

I'm not interested.... I've got enough other first-gen ideas halfway to fruition that I'm not even gonna try to start anything else.. LOL

--Danny

 

only reson i mentioned it is i COULD have them cut, AND get the metla for FREE. so it would be a heck of a lot cheaper just a thought though