KDW

Got a JDM Rx-8 6-port with a broke engine for $1,270...its engine has a bearing failure. Both rotors spun its bearings. Stationary gear main bearings are both heavily scratched. One of the rotors bearing are even hard to remove from the eccentric shaft. Both rotors are scratched where the bearings slides. All seals...apex, side and corner seals are all intact...no cracks etc.

Previous owner said that only 1 rotor is running.
Is it possible for one rotor not to run due to a bearing failure? considering that all the seals are intact?

Also when I dismantled the engine..I noticed the stationary gear main bearings are with stopper screws version
I have 2 broken Rx-8 4-port engines and will be the source of parts to rebuild the 6-port engine...but I noticed that its stationary gear main bearings have no stopper screws version. Can I use the stationary gear from the 4-port? the one with no stopper screws?

Thanks

CaymanRotary

I doubt it ran well at all with spun bearings. Even with seals intact it wouldn't be easy to get started. If one rotor was still working the engine would kind of start and work but it wouldn't run for long. Definitely wouldn't be able to idle.

You'll need a stationary gear for a 6 port, you cant use the 4 port stationary gear. However, rotors, rotor housings, e-shaft and oil pump are the same between the 4 port and 6 port. Everything else on the 4 port wouldn't really be helpful to you. Are the irons themselves trashed as well?

Wouldn't recommend reusing any seals even if they are intact. Better to buy a rebuild kit that has everything else you are gonna need. All comes down to the current condition of your 6 port irons though. If they are trashed as well, its gonna get real expensive real fast.

Loki

iTrader: (1)

I'd buy a freshly rebuilt engine at that point. It will be cheaper in money and time than piecing together something that works properly. Emphasis on "properly", you don't want to do this again in 10k miles

KDW

Why do the 4 port stationary gear will not work with the 6 port? Looks like its just a revision? whats the major difference aside from the stopper screw? Thanks

CaymanRotary

Dont know the specific reason why, I just know they are different, thus I couldnt recommend using the 4 port stat gear on a 6 port motor. You could just get a good used set of stat gears from ebay or something.

Loki

iTrader: (1)

The 6-port stat gears use a different metallurgy. Mazda saved costs on the 4-ports where stresses are lower by skipping hardening steps. I don't know how much difference it really makes, but finding out the expensive way sounds. .. expensive.

KDW

Another question...where is the registration engine number located? Front or Rear rotor housing? Thanks

CaymanRotary

On my 2004 RX-8 the engine number is above the trailing plug on the first rotor housing. It is a 6-digit number with no letters. If there is no number then that engine might be a rebuilt or reman engine. That code is useless, all it does is tell the dealer whether the engine had been replaced already or not for warranty. You get more info on your car from the VIN#.