Apex seals

Draco · Post by **Draco** » Thu Oct 16, 2008 9:09 am

Hi guys.....not a 200sx question.....sorry

On a 13B rotery engine, what does the apex seals do-where do they fit?

Sokar · Post by **Sokar** » Thu Oct 16, 2008 9:31 am

I can give a quick answer, but if you're asking about something as fundimental as apex seals then rather do a "crash" coarse at how stuff works: http://www.howstuffworks.com/rotary-engine.htm

It will explain it quite nicely...

Draco · Post by **Draco** » Thu Oct 16, 2008 11:24 am

Thanks....I might buy a RX 7......

Draco · Post by **Draco** » Thu Oct 16, 2008 11:41 am

Ok....I read some....they refer to "at the apex there is a ......"

Me knowing nothing about this....what does this mean....how hard is it to replace this?

Enzio · Post by **Enzio** » Thu Oct 16, 2008 12:04 pm

To replace apex seals the rotor has to be removed - in other words: complete rebuild.

That was always one of the main concerns with the older rotary cars that didn't have the better type of apex seals used today. Modern seals are made from better materials and can handle a lot more strain - but are also more expensive.

Some tuned motors need to rebuilt quite often - sometimes every 10k km's

Sokar · Post by **Sokar** » Thu Oct 16, 2008 12:07 pm

Draco wrote:Ok....I read some....they refer to "at the apex there is a ......"

Me knowing nothing about this....what does this mean....how hard is it to replace this?

On page 3 they have a cross section of the rotor with the apex seal labelled.

The apex seals are basically piston rings, replacing them means motor out, stripped, new apex seals, side seals, oil seals, water seals, bearings etc etc. Its a full rebuild... I got quoted around R15k should my RX8 kick the apex seal bucket...

The RX7 you looking at, I assume looking at your R25k budget this must be a 1980s "FB" that we had locally? If so it can be a 12A or a 13B motor, cost is the same wither way.

Hope that helps, if you wanna chat to the rotary experts I can give you the number for Stefan at RTT in Boksburg.

Riekert · Post by **Riekert** » Thu Oct 16, 2008 12:30 pm

http://capetown.gumtree.co.za/c-Cars-fo ... dZ80666448

Draco · Post by **Draco** » Thu Oct 16, 2008 12:55 pm

Riekert wrote:http://capetown.gumtree.co.za/c-Cars-fo ... dZ80666448

No.......

Draco · Post by **Draco** » Thu Oct 16, 2008 12:56 pm

Thanks Sokar

Riekert · Post by **Riekert** » Thu Oct 16, 2008 1:20 pm

Draco wrote:
Riekert wrote:http://capetown.gumtree.co.za/c-Cars-fo ... dZ80666448
No.......

nah man its just the shape that I was referring to....

Draco · Post by **Draco** » Thu Oct 16, 2008 1:21 pm

OK.....sorry....

Riekert · Post by **Riekert** » Thu Oct 16, 2008 4:05 pm

Draco wrote:OK.....sorry....

all good dude!

veecee · Post by **veecee** » Thu Oct 16, 2008 6:31 pm

the FB rx7 is closest to the photographer and has its lights up.

then there are two rx8's.

and the white car furthest away is an FC rx7.

draco - if you are able to get an FC go for it man. those cars are awesome. i reckon FB's are probably great too, i just dont know too much about them!

and the best of them all is the FD, in the foreground of the pic below:

veecee · Post by **veecee** » Thu Oct 16, 2008 6:37 pm

also draco - some pics...

an apex seal as seen through the exhaust port. that particular one is damaged. the apex seals separate the three combustion chambers of a single rotor.

on the pic below you can see the 3 pointy bits of the rotor. those are the apex's of the rotor. the seal for each apex is inserted into that funny round shape at each end (pointy bit).

Vlade · Post by **Vlade** » Fri Oct 17, 2008 4:12 am

umm interesting... also been reading up on these rotor things they call motors

interested that oneday, if my SX gets sold, I'll be able to buy a car this side... and yeah FD was one of my cars on the my list of have to have's

but yeah after much reading i decided I would not buy one where the motor have not been rebuilt... the 13B's tend to blow after 100 000km (which is very common here), on TradeMe (the local Ebay) most FD's go for sale shortly before or after 100 000KM, although there are plenty of cases were they have run 2 to 3 times that much before kicking the bucket...