olddragger

iTrader: (3)

how did you guess!

Don now you mind that little woman--crank up that John Deere tractor of yours and get er done dude
od

BigMikeATL

Could you elaborate on why 04 and 05 8's rarely make it 50000 miles? What percentage of these are failing prior to 50k?

I have an 05 with 57000 miles... how concerned should I be?

Nemesis8

iTrader: (3)

^ I'm medium rare I guess 85K on an 09/03 build

Hey Paul, make sure you add the Mazmart oil pressure fix before you bolt that BHR oil pan back on.

SilverEIGHT

My 05 went at 58K. Here's a rundown on the Georgia group. This is just from active members. I think there were probably a lot more that didn't post.

dbright007 - 8500 mi., (oil weight?) normal driving, AT, NA
WHENSON417 - miles?, (oil weight?) normal driving, MT, NA
olddragger - 52,000, (oil weight?) synthetic, light track, MT, SC
SilverEIGHT - 58,8000 mi., 5w20, light track, MT, NA
phlash - 66,000 mi., track, MT, NA
phlash - 600 mi. on replacement engine, MT, NA
XAreXAteX - 22,500
ATL-GP - 48,162 mi., 5w20, normal driving, MT, NA
Kurt Bob - 97,000 mi., Autocross/Track
x-attack - 70,500 mi.
9G Redline - 83,1--miles, RP 5w30 since 15k Spiritedly daily driven, NA MT.
L8APEX - 97,000 mi., Track
olddragger - light track, MT, SC

We have debated percentages but there's really no way to define it properly.

Flashwing

My 2005 currently has 93,500 miles on it with an origional engine, tranny, clutch etc.

The vast majority of engine failures are due to failed or failing seals whether they be apex or side seals. The reason the 2004 and 2005 models have had the highest failure rate is due to the lack of necessary OMP injection.

Emissions compliance is a huge issue when it comes to producing vehicles. Mazda had to deal with the fact that the rotary provides a lot of challenges in this area. Burning oil certainly made the situation worse and oil also can ruin your cat as well. So, faced with strict regulations and also new federal rules requiring emissions equipment to last 140,000 miles they made some compromises.

Mazda has since released various PCM reflashes which, along with other items, increases the OMP injection.

Should you be concerned? The only way to tell is to get a compression test. Otherwise, making sure you have the latest PCM flash and also pre-mix a bit and you'll be fine.

There are other measures you can take to help but they are for other threads. Feel free to contact BHR at any time and we can point you in the right direction.

olddragger

iTrader: (3)

maybe we should ask who HASNT had to have another engine?!
OD

olddragger

iTrader: (3)

He beat me to it!!

robrecht

ASH8 has an internal Mazda source who said its been 25%. A year or so ago, someone put up a poll here and there were about 28% with failed engines (out of 167 votes), most of which were 04s and some 05s. So the percentageo of 04 engines that have failed must be pretty damn high. Then of course there are tons of rebuilds that also failed before Mazda set up there own rebuild center.

Charles R. Hill

iTrader: (7)

Here's another angle;

In selling the 340+ BHR Ignition Systems I have found that of those who bolt the kit on and then contact me to say they saw no benefit and still experience hard starting when hot (this condition is a classic symptom of low compression but people always use coils as a way to swap parts as a diagnostic method), the vast majority of them are '04-'05 models and will, inevitably, test with low compression.

As a result of noticing this trend (but I haven't kept notes on it), I had to rewrite the installation instructions to say that coil upgrades are not intended to cure a poorly-running engine that has problems unrelated to weak coils.

ASH8

I am also "curious" as to why 04 and 05 had an "issue" concerning failures...

From my point of view, apart from some very minor parts change the internals in ALL the RX-8's are the same, that is 2010 parts will fit an 04 RX-8.

But, yes the only differences as Todd said were the upping of MOP rates, but it still does not get to the middle of the Apex Seal...that's is why you must pre-mix.

The other reason 04-05 seem to have a "high" failure rate is also being 'skewed' somewhat because these were the 2 years where the 8 sold in much higher unit/sales numbers.

ASH8

Hell...even the Rotor Housing LARGE 'O' rings (Square Orange/black inner) and Black Outer Housing O rings are ALL the Same for the past 25 years...

Yep, they are the exact same ones from a 1985 FC RX-7 and also the same in all FD RX-7's in ALL RX-8's.

9krpmrx8

iTrader: (46)

But a compression check showed low numbers on your engine right? So, that combined with your low dyno numbers means it's probably is on it's last legs right?


Very true.

nycgps

iTrader: (1)

*Raise my hand* <---------------- part of the "low compression 2005 group"

Ash8, we all know how Mazda screwed the 03-08 RX-8 owners. increasing the OMP is just an "band-aid" thing, no way its a "once and for all" solution. Premix is a must.

Hell, I have a feeling even the 09+ models will need a premix ... just not as much as anything before (including all FD,FC,FB ... and so and so.)

Charles R. Hill

iTrader: (7)

I have never pre-mixed.

ASH8

Mazda totally re-engineered their MOP system for a reason, and re-introduced a Center Oil Nozzle/Weeper in the Series II RX-8 which they have always had in every other rotary since they started Direct Apex Seal Oiling.

The S1 RX-8 was the first not to have a Middle Nozzle.

FC RX-7 was the first to use a Middle Nozzle.

Charlie, have you seen any concave wear on your Apex Seals like Paul (Mr E) at Mazmart have shown?

Flashwing

My compression was in the low 7's. It's far from it's "last leg" as I still have no problems running the **** out of it.

Despite my own habits, I think the jury is still out as to whether pre-mixing is the save or not. We've seen failures from people who pre-mix and, like Charles, we see motors do just fine without it.

ASH8

You have seen failures from owners who have pre-mixed on a new motor from Day one???, or from owners who have started pre-mixing after their engines have done 40-50,000 miles???

I would like to hear and even better see a naked engine pre-mixed from the start of it's life...I thought that Jury was still out.

StealthTL

iTrader: (1)

I pre-mixed, (heavily) since day One, July 23, 2003.

Unfortunately that engine blew up due to a poorly tuned turbo, and I never got to see the innards.....

Doh!

robrecht

But you've maxed out your OMP with the AP (& Sohn w 2-stroke), right?

Huey52

iTrader: (2)

Inevitably??? Granted I've only got 25k on my '05, but it runs better the ever. Maybe I've got a 'good' one.

TeamRX8

iTrader: (25)

This is the most blissful thread I've read in a long time ...

JinDesu

iTrader: (2)

You could wait for my engine to die. It was premixed starting at around 300 miles. I'm at 6000 miles now.

Might take a few years though, considering my driving rate

Mazmart

iTrader: (12)

Just so that everyone understands: Typical engine failures of an RX8 are not caused by oil starvation, bearing wear or anything of that nature. RX8s do not typically have engines fail by 50k (Even 04-05s). I would guess under 100k to be common (And that's an educated guess since we've probably built more than anyone outside of Mazda's reman program. Having said all that, apex seal, side seal and spring wear with excessive carbon buid-up are the main culprits that stop someone from driving their RX8 with enough concern to take it to the dealer, resulting in an engine replacement.

Now to the oil pressure mod kit: Extra oil pressure is a good thing on these motors, especially those driven harder and with extra loads being applied (Forced induction and tracked cars especially) when it results in 'proper' oil flow and improves motor cooling characteristics. I think it can only help with the excessive bearing wear that we've seen. I still put the main blame for that wear on oil viscosity choice since we've seen automatic motors with it as well (Generally not seeing as much high revs and or hard driving). Sharp people here have pointed out that these engines do run the lowest oil pressures that Mazda has run in a while and we are bringing that to the range it was at some point. This summer will be a good testing time to observe whether water temps are improved by the heat being removed through the oil system as well. One of the unplanned benefits of this mod are the extra potential safeguard in the event of failure of the front eccentric thermostat; the added pressure/supply would be quite welcome.

Here's the kit for those who may be interested:
http://www.mazmart.com/PartsList.aspx?id=29&n=NEW&m=6



Paul.

Nemesis8

iTrader: (3)

I'm batting 3 for 4 off that page.

Charles R. Hill

iTrader: (7)

And my comparitively miniscule rebuild experience with the Renesis reflects this exact same thing, so I concur. What I was saying was of the engines that I have consulted my customers on which ended up having low compression, the majority of them were from the '04-'05 model years.

As for my engine, I have never premixed. When I rebuilt my '04 model it had 49,540 miles on it and the apex seals were "troughed", big time, on the sides that contact the rotor tip. After rebuilding it I installed the Sohn OMP Adapter and Mazmart Oil Pressure mod and, several months later, the Cobb AP from MazdaManiac. I did not replace my rotor housings. My OMP volumes are not "maxxed" but they are about 3x what Mazda proscribed with the factory PCM. I currently have 110,000 miles, total, on the car/engine and it starts with a tap of the starter (warranty swap of battery/starter pursuant to the TSB) and laid down 213 rwhp as of last year, as well.

As for whether or not raising the oil system pressure "should" be done; I have seen no problems from it with my own engine, it is a HIGHLY suggested mod by people with far more rotary experience than any of us at BHR (and I am talking with as many as I can so as to try and develop a synopsis to present), and I have yet to tear my own engine down to see any potential results/effects from it.