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88 FC Apex Seal Question

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Old 06-06-10, 04:25 PM
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Exclamation 88 FC Apex Seal Question

hi everyone, im new too the site and just recently purchased an 88 FC N/A.

I bought the car for $500 canadian dollars. 13B injection, still drives great and it came with a parts motor. The guy i bought the car from said it needs an "apex seal" in the rear rotor. I havnt any idea how these rotory engines work so i was hoping for a little in sight lol.

When i start the car up it blows a little white smoke just on start up. other then that its still drives fine. My question is, is this something i should looking into replacing right away? If i drive it like this will i ruin the engine?

In a month or two im having the egine takin out too have a full engine gasket kit done, and thats when i plan to replace this apex seal. Please anyone who can educate me further with this and help me understand it would be muchly appreciated!

Brodie
Old 06-07-10, 01:04 AM
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He said the engine in the car needed an apex seal, or the parts motor did? If a 2-rotor engine is missing an entire apex seal (or one is damaged), 2 out of 3 faces on one rotor will not create any compression. The engine would be down a full 1/3 on power, usually idle poorly and likely be very difficult to start. It would be very obvious that something was very wrong.

This link should be helpful to you: http://www.rotaryengineillustrated.c...-rotors-2.html
Old 06-07-10, 07:09 PM
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sometime i have problems starting it and today its been hesitating badly. when i put it in 1st, it will go up too 3 grand an loose ALL PULL and get extreamly close too stalling.
Old 06-07-10, 07:54 PM
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Do a search of the 2nd gen section for "compression test". If you're experiencing power loss, a compression test will be able to confirm a blown engine.
Old 06-08-10, 12:19 PM
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thanks ill cheak that out. Iv heard people talk about "3800 RPM Hesetation" and it matches the sypomes of whats happaning to my fc. It says too cheak all your ground wires and even disconnect them all clean them and put them back on? Could it also possably be a port valve actuator not working?

Anyways tell me what ya think, your a big help. thank you.
Old 06-08-10, 12:28 PM
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It's not going to be an aux. port actuator. You can have them both closed and not notice it. There is top-end power loss, but the midrange torque will still be close to normal.

It doesn't hurt to clean up grounds, but it's most likely not your issue. 3800 RPM hesitation isn't a huge power loss.
Old 06-08-10, 02:35 PM
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ok so i cleaned up all the grounds and like you said didnt make a difrance. i noticed today that im only getting this power loss driving forword :s I can drive as fast at i want in reverse and nothing happands lol? Problem with the trasmition or clutch perhaps? It starts right up fine now, idols at 3 grand for a secound when you first turn the key then it idols between 900-950 fine. I was talking to the guy i bought the car from and he said with the apex seal its only a corner peice thats worn out on the back rotor. i can free rev it as high as i want in nutral but it will only make it too 3 sometimes 4 grand moving forward. chris a buddy of mine with a 91 rx7 mentioned something about a limp-mode maybe?
Old 06-08-10, 03:19 PM
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An apex seal is not a "corner piece"; that would be the corner seal. Worn out = low compression. Click the link I provided before for pictures.

S4s do not have limp mode, but failed electronics can still cause problems. You can use the Factory Service Manual to troubleshoot.
Old 06-08-10, 03:56 PM
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alright, thanks for all your help.
Old 06-09-10, 02:49 PM
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so i called mazda today too get a quote on the installation off all new apex seals and corner seals and tthey told me they dont do that? they told me to buy a new 13B. Its only my corner seal thats worn out and they told me theres probebly big damage to the rotor housing. whats your take on this?

I bought all new apex seals and corner seals already, i just need the springs. Car still fires up right away.
Old 06-09-10, 10:31 PM
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Mazda Dealers don't rebuild engines. They just install re manufactured engines and send just the cores back.

You will have to find a rotary rebuild shop to actually rebuild your engine. Or do it yourself.
Old 06-10-10, 12:30 AM
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ok i understand that, but what do you think about my rotor housing? do you think its damaged? as i said the car still starts up right away with no problemes. idles at 3 grand when you first turn the key then idles steady at 1 grand.
Old 06-10-10, 07:49 AM
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You never really know if its damaged until you crack it open. If I were you I would have a compression test done and see what the results are. If you have good compression over all three faces then you don't have a seal problem.
Old 06-10-10, 12:01 PM
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the guy i bought the car from did the compression test and said it was low in the back rotor. then told me it was a corner seal. Said the compression wasnt crazy low but it has dropped a little. thats sucks, i wish i could tell if my rotor housing was damaged....i called a shop today for a quote on all apex seal installation. they told me its about a 19 to 21 hour job and im looking at 1600 too 2100 bucks. i just dont wanna sink this kinda money into it if the rotor housing is f*cked. Would i be better looking for a used 13b?
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