I got my 2004 RX8 with 99.5k miles, engine needs rebuilt! Took engine out and to my suprize I noticed that there is a remnant tag on the engine. Tore it down and vola!
BTW based on the carbon build up on the rotor I would dare guess that this engine did not have more than 20k on it.
The oil chain is loose as a goose, bearings front, rear, rotors are gone, excentric shaft is history...

 

Are you saying this was a Mazda re-manufactured engine or some other person or company did the rebuild?

It's been known for some time that the earlier rebuilds by Mazda were often of poor quality and that people would have a lot of issues with them.

 

Yes, Mazda Reman tag

 

Well without knowing when it was installed, how many miles are on it, or how it was maintained, these pics don't mean much. Mazda remans are hit or miss depending on what parts are or are not reused. That said, plenty Mazda remans last 75-100k which is pretty good for a used engine.

 

Also what 9k said.

 

The car has 99,5k miles on in. I guess the remnant has no more than 20k miles on it based on the carbon build up on the rotors.

I forgot to mention in the original thread that the oil injection lines on the back rotor were broken off an oil was squirting on the exterior of the engine. needless to say the carbon buildup and the wear of the rotor housing is evident in the pics!

 

Well mileage has little to do with the amount of carbon build up. The failed oil metering lines will play a role in failure but they have nothing to do with that bearing wear.

For example this is my buddies rotor and rotor bearing from his Mazda reman that died at 30,000 miles. Castrol GTX 5W20 was used and it had on time maintenance and care.

 

Now this is my rotor and bearing from my Mazda reman that was failing (pulled before it stopped running to prevent further damage) at 26,000 miles. Fully synthetic Mobil1 0W-40 and on time maintenance.

 

Both of us drive our cars similarly and in the same environment, but of course there are many variables. Both of us were out of warranty with over 100k so we got a chance to see the internals but we don't know all of what new or used parts were used. As we know from sleepy-Z (worked at Mazda reman plant) the bearings, seals, etc. are new but the housings and other major parts are often reused or replaced with new stuff so you never know what you are getting exactly.

 

So, what you're saying is that OP shouldn't make broad generalizations based on test results from a sample size of 1 where the population is of unknown provenance?

That's crazy talk.

 

It's hard not too, even with our personal rather poor reliability experiences with the Renesis I often remind people that there are many variables in a particular engines mode of failure and so you have to try and take a step back and really think about and even then sometimes there is just nothing that could have been done to prevent it. Sadly when you are under warranty you never really learn the exact reason why the engine failed.

Also, people need to understand what a remanufactured engine from Mazda and many other builders really is. Most have the idea that they are getting a new or close to new engine and that is just not the case. Plus, as we know from many new engine failures back in the day, how that engine is put together is very important.

But once you accept that the Renesis has flaws that cannot really be overcome, you will feel a lot better about it going forward as you can make a choice as to whether you want to deal with the unreliability (in general engine reliability terms) or not.