Rotary mechanics, and other pre-purchase questions
 

Hi there, new member here from Canada, reading and researching before purchasing what will most likely be a 2005-2006 RX8.

Firstly, I was wondering if its required to take your RX8 to a specific rotary capable mechanic for service? They are the only type of car on the road with this engine so I assumed that some sort of specialized service may be required.

Also - I've been reading that a compression check is highly advised before buying a used RX8. How long does this take, and is this only available at a Mazda dealer? Is this something that I will have to ask the seller to do for me or is it something where I can book an appointment, and take the car for a test prior to purchase? How does one go about having this check done!

More questions are likely to follow, thanks for reading.
Cheers!

Before you purchase an rx8, it's better to get an engine compression test, so that you know how well the engine is doing. Have a Mazda dealership do the testing, and let the seller pay for the testing or both of you split the difference.

You have to ship the car back to Japan for oil changes, so that they can service it there right where they build them.:rollingla

And before you ask more questions....read the stickies!!!!!!

the Rx8 is nice, in that the engine requires nothing except fluid and spark plug changes, and if there is a problem it just gets replaced with a new/rebuilt one. the rest of the car is really straightforward too, so in a perfect world you shouldn't need a rotary specific mechanic, you just need one with a brain.

i would also suggest a compression test. the dealership should have a specific rotary engine tester, rotary shops should also. test takes around an hour, and while they are under there, you can check the brakes and the tires and stuff.

mike

that right there is the problem!!!!

Thanks for the replies, I'll take PistonHater's first comment with a grain of salt ;)

I did read through a bunch of stickies, the more you look....the more stickies you find. I ended up answering my own question when it came to compression testing - where to get it done and whatnot. I found a few threads that showed results from a compression test. I also found this picture which describes the ideal values for compression on a new car (588kpa?). When buying a used (2005-2006) RX8, what kind of values should I be expecting? I see #1 is ranging from 380-430, which was mentioned as definitely being low, and the second being fairly close ranging from 528-554. Is there a sort of safe-margin like +/- 10% ?

Assuming you are all RX owners, did you purchase yours used?

1. my comment was meant as a joke, hehe. For regular maintenance, there's nothing about the car that is substantially different than other cars. But rotary specific concerns, such as compression tests, internal engine work, etc, you definitely need a rotary specific place.

2. In regards to compression tests, there are different ways of calculating that, and many are very confusing!!! Most dealers will give you a numeric value from 0.0-10.0 i believe. Anything below 6.0 means fail compression. Anything above six, even if it's 6.1 (or 6.2,6.3...7.0, 7.3, etc) means 'pass' even though it may mean borderline failure. Getting a 10.0 obviously means is the highest compression value.

There are other variables such as altitude, vacuum test readings, stupidity of the tech performing the test, etc.; that could affect the readings of the compression test. So if they find that yours 'fail', they will probably perform a bunch of other procedures (testing ignition, exhaust component, decarb procedure to 'clean' engine inside) and then re-test to double-check.

If the car passes the test, then you have to pay out of pocket for the test. If it fails, then you should not have to pay - as long as the car still has engine warranty left.

from the shop manual:

Read the compression and engine speed.

Compression pressure
• Standard: 830 kPa {8.5 kgf/cm2, 120 psi} [250 rpm]
• Minimum: 680 kPa {6.9 kgf/cm2, 98.6 psi} [250 rpm]
• Difference in chambers: Within 150 kPa {1.5 kgf/cm2, 21.8 psi}
• Difference in rotors: Within 100 kPa {1.0 kgf/cm2, 14.5 psi}

compression is linked to engine speed, so there is a correction for engine speed.

https://www.rx8club.com/attachment.p...9&d=1341941196

Hmm, maybe I'll check the regional forums and see if anyone in my area has some recommendations. I live in a fairly large city of about 500k, just outside of Toronto, so I'm hoping that I might find something, although I've never heard of any.

I've been seeing 2005's for around 8-9k with ~100km (60mi). That was my sort of target range, but I'm thinking now that I should go with a MY2006 if possible to get some warranty headroom. They're more in the 10-12k range though. For that extra price, I could basically buy a new engine if mine failed....=/


@j9


The picture I pulled from this thread (New and Potention Owners Start Here) and posted above in post #6 shows much different values than the ones you linked. :confused:

Hmmmm, Barrie or Tri-city area? There are quite a few gta 8 drivers that would be able to give imput in the Canada section. Good luck with your purchase and post some pics!

Stoney Creek, or Hamilton if you prefer. Barrie is my winter get-away :)

Will be all over it when the time comes, trying to do my research and save up a little nest egg :p