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2 Years - 2 Engines - I'm Done - Goodbye RX8

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Old Jul 20, 2007 | 02:00 PM
  #51  
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Originally Posted by nycgps

Human being's nature : Whenever something bad happens, will always blame it on something *ELSE* instead of themself.

^^ what are you, the forum idiot or something?
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Old Jul 20, 2007 | 02:12 PM
  #52  
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Yeah, I didn't get that. NYCGPS, are you suggesting that the OP failed his own engine?

To anyone else being a fanbois on this - walk into ANY Mazda dealer in AZ or NV and count the number of '8s on the rack awaiting engine replacements.
Talk to the techs and see how many they've done.

I love my '8. They'll probably bury me in it.
However, if an owner in Vegas follows the severe maintenance schedule in the owner's manual and drives it how the manual suggests the car should be driven, he will have a failed engine at a relatively short interval. Drive it harder and you will fail it quicker, de-carbon not withstanding.

Really, at times, it is too hot to drive any rotary in Vegas and Phoenix. They simply do not have the thermal characteristics to survive the high ambient temps and the cooling system just won't keep up.
You can increase the flow of the pump, put in a bigger rad, run the fans all the time, use synthetic oil and pre-mix to your hearts content, but when the ambient is over 110°F and the surface of the road is 160°F or higher, there just isn't anything you can do to keep the thermal stress down. Its an engine killer and that is the crux of my assertion - for the average owner (especially in desert climates), the Renesis is not ready for prime time.
For an enthusiast, you will modify your behavior to protect you motor.
The average commuter dad (to whom this car was specifically marketed) is not that enthusiast.
[That owner may not even notice they have a failed motor!]

Last edited by MazdaManiac; Jul 20, 2007 at 02:21 PM.
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Old Jul 20, 2007 | 03:58 PM
  #53  
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Originally Posted by LionZoo
Agree with MazdaManiac, though I'd like to add that if the OP received a reman that might explain the lack of durability of his second motor.

I'm moving back to LA in a few days and in preparation I've installed the Mazsport fan mod for the heat and traffic. I also plan to flush my coolant soon and possibly replace it with pure water plus water wetter. I thought about Evans, but decided against it. However, I'm sure a normal owner would never even consider these things to combat the heat.

Pure water is not the way to go for a rotary. It's basically a sandwich of different metals, and needs the anti-corrosion protection from coolant.
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Old Jul 20, 2007 | 04:13 PM
  #54  
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Originally Posted by Nubo
Pure water is not the way to go for a rotary. It's basically a sandwich of different metals, and needs the anti-corrosion protection from coolant.
Yeah, I didn't mention the Water Wetter. Plenty of anti-corrosion protection and pump seal lube in that.
Water Wetter actually tested the highest for corrosion protection out of any of the coolant additives available.
http://www.water-cooling.com/article...aterwetter.php
http://www.pegasusautoracing.com/Article-004.asp
http://www.wc101.com/reviews/Additives/

Last edited by MazdaManiac; Jul 20, 2007 at 04:17 PM.
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Old Jul 21, 2007 | 12:29 AM
  #55  
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Originally Posted by shazbot28
Um Rob, we're trying to help not scrutinize you. The fact is oil can have a bit of an effect. There's more lean (for hot locations) and more thick (for colder locations).

If you didn't want help, then please stop wasting our time.
?? I think you have that backwards.
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Old Jul 21, 2007 | 03:01 AM
  #56  
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Originally Posted by SumRX8
?? I think you have that backwards.
that's what I thought at first but didnt comment since I wasnt sure... not to go off topic, but can anyone varify? thanks
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Old Jul 21, 2007 | 08:40 AM
  #57  
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Yes, that's backwards. Oil naturally thickens when it's cold out, and thins in summer temperatures. To compensate, oil for winter is thinner and oil for summer is thicker.
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Old Jul 21, 2007 | 09:12 AM
  #58  
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ya, backwards that's why racing oil is so thick
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Old Jul 21, 2007 | 09:15 AM
  #59  
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this thread really scares the crap out of me, as a newish driver of the 8, and someone who does their best to do what the manual, (my only hardcopy source of recommended upkeep) to find out that it might not be enough... wtf...

okto, i wish you the best of luck and i genuinely hope everything goes in your favor, no one should have to put up with this type of ****
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Old Jul 21, 2007 | 03:29 PM
  #60  
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Originally Posted by shazbot28
Um Rob, we're trying to help not scrutinize you. The fact is oil can have a bit of an effect. There's more lean (for hot locations) and more thick (for colder locations).

If you didn't want help, then please stop wasting our time.
Are you guys saying that 5W 20 might not be the right oil to run in my car if it runs terrible in the heat?
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Old Jul 22, 2007 | 08:29 PM
  #61  
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Out of all the 8 owners I know in Phoenix, quite a bit, it seems that myself and Flashwing are the only ones that haven't needed a new engine. Personally I wouldn't be to upset if mine went twice in as many years, since this car has been kind of a let down.
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Old Jul 22, 2007 | 10:42 PM
  #62  
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From Racing Beat's tech tips on water cooling:

"In the past, Mazda's stock coolers were more than adequate adequate for not only stock applications, but also for mildly modified street engines, assuming the cooling components are in good condition. However starting in 1993 the capacity of the stock cooling system was designed by Mazda to barely meet the needs of the stock car with no excess capacity for very demanding situation or modifications that increase the heat load on the engine. Based on the number of tests, we believe the primary cause of this problem is aerodynamic. In both the 1993-95 RX-7 and the RX-8 the air path out of the radiator is convoluted and restricted - leading to high water and oil temperatures. We have tried larger radiators, and to date, they have not helped. We have seen some improvement from improved sealing and directing the air into the radiator (using a spoiler lip under the vehicle) to create a lower pressure area under the car, to remove hot air."
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Old Jul 23, 2007 | 01:13 AM
  #63  
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I find it amazing how some members on this forum refuse to admit their ancestry lies with the previous 13b versions in the FD/FC.

The corner seals are slightly redesigned and the side seals are also, and relocated slightly on the rotor. There's a cutoff ring to prevent premature deterioration of the oil control rings due to side exhaust heat, and there's a side exhaust port. BIG FRIGGEN DEAL.

Yes, it is different, and there are slightly different modes of failure, strengths and weaknesses.

You guys act like the renesis is as dissimilar to the previous 13b's as a jet engine is to a chevy 350. It's just not so.

Older rotaries usually die all at once...they run pretty well even with weak compression, but eventually an apex seal breaks. You don't hear it, but the engine pitch changes and you lose all your power and the engine vibrates and won't idle. Sometimes you have an internal coolant seal failure and high mile engines start getting oil consumption and fuel dilution issues due to flattened oil control rings.

The same methods of failure apply to the renesis, except that the engine control system seems to be so accurate on the renesis that even WEAK compression (nothing broken, just some premature wear) will cause them to start, idle, and accelerate poorly...and these are the symptoms you guys are calling "blown" engines. To engine rebuilders, this is not really a blown engine, it's just a weak one that's undesireable, but is generally a fully rebuildable core and just needs seal replacement.

There is a lot of work to be done in the rx8 community in the coming years. I have my work cut out for me.
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Old Jul 23, 2007 | 02:08 AM
  #64  
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I don't think anyone is denying the "ancestry" of the Renesis. Plus, I think you understand that "blown" is another misnomer. A "blown" motor is simply one that has lost its rated performance because of accelerated wear of one or more of its sealing components. For an owner that is still under warranty (which is still the majority), this motor is effectively "blown" since it will simply be replaced, regardless of its failure mode.
People have a reasonable expectation that a $30k car won't have a motor that produces less than its rated performance after only 30k - 60k miles.
The thing is that when a Renesis "blows", it isn't in a state that is as easily rebuildable as an REW because of the way it fails. The reciprocal damage from a major seal failure means a lot more parts get trashed.
At this point, low-miles motors are starting to pile up in the yards for a price that is less than the cost of a rebuild. That will most likely continue as the cars are destroyed at a rate that surpasses the motor failure rate.
The retail cost of rebuilding a Renesis is still well over $2k.
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Old Jul 23, 2007 | 02:19 AM
  #65  
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I have to disagree with some of that. For purposes of this comparison, we'll discard labor charges and assume the person is doing their own work.

1) if the "blown" condition you refer to is simply weak compression causing harder starting, rough idle, and weak power output, then it's entirely LIKELY that the engine ONLY needs a seal kit. This can be obtained for a grand, or less, depending on what wear is found inside on each of the seals. I see no used engines floating around for a grand yet, and barely any under 2.

2) most REW's "blow" due to broken apex seals. This always requires a rotor, rotorhousing, plus seal kit. Depending on whether or not you get the replacement hard parts new or used, the cost is around $400-1000 plus the $500-1000 in seals. A few REW's are said to be "blown" with bad coolant seals, which is a much easier fix, for just a few hundred dollars in seals, unless the owner has gotten the engine very hot and warped something.

3) comparing the "my dealer says I am getting a new motor" posts with the "parting out wrecked rx-8" posts, I would say you are incorrect about the supply and demand of used engines. Right now, 95% of those engine replaecments are being done free by the dealership. When warranties run out, the few used engines floating around will begin to get snatched up like hotcakes and that theory will go out the door.

4) if a renesis truly does "blow" up and break apex seals, you are correct in that the damage will be more extensive than the older rotaries, with the apex seal chunks wedging between the rotor and exhaust port, taking out the adjacent irons as well, and raising the cost another $700 above what an older rotary might cost.

5) your comment about "owners of a $30k car do not expect their engine to produce less power than ratings" has entertainment value for me...almost every owner of a renesis already has an engine that produces less power than even the revised ratings. But, as the whole HP ratings vs. output discussion is a sore subject to the forum gods, I will not take it there on you.
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Old Jul 23, 2007 | 02:36 AM
  #66  
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Originally Posted by RotaryResurrection
I have to disagree with some of that. For purposes of this comparison, we'll discard labor charges and assume the person is doing their own work.
Not a necessarily good assumption, based on the "type" of folks that own the RX-8 at this point, but I digress.

Originally Posted by RotaryResurrection
1) if the "blown" condition you refer to is simply weak compression causing harder starting, rough idle, and weak power output, then it's entirely LIKELY that the engine ONLY needs a seal kit. This can be obtained for a grand, or less, depending on what wear is found inside on each of the seals. I see no used engines floating around for a grand yet, and barely any under 2.
Used motors are $1800 to $2700. A "seal kit" for the renesis (all seals and o-rings) is about $1600. Since the user is doing his own labor in your example, he is adding a few days of work for a savings of $100 to $1100. There is a lot of variability in that entire formula for a multitude of reasons.
Furthermore, the loss of compression has often been out-of-spec wear to the irons and housings. Lack of lube is a big deal at the moment.

Originally Posted by RotaryResurrection
2) most REW's "blow" due to broken apex seals. This always requires a rotor, rotorhousing, plus seal kit. Depending on whether or not you get the replacement hard parts new or used, the cost is around $400-1000 plus the $500-1000 in seals. A few REW's are said to be "blown" with bad coolant seals, which is a much easier fix, for just a few hundred dollars in seals, unless the owner has gotten the engine very hot and warped something.
This same repair on a Renesis (housing, rotor, seals, o-rings) is $2500 in parts.

Originally Posted by RotaryResurrection
3) comparing the "my dealer says I am getting a new motor" posts with the "parting out wrecked rx-8" posts, I would say you are incorrect about the supply and demand of used engines. Right now, 95% of those engine replaecments are being done free by the dealership. When warranties run out, the few used engines floating around will begin to get snatched up like hotcakes and that theory will go out the door.
The average RX-8 owner will still bring his car to the dealership for the $6k reman engine replacement rather than look for independant garages to do the same work for a similar price. A reman from Mazda is about $4200.

Originally Posted by RotaryResurrection
4) if a renesis truly does "blow" up and break apex seals, you are correct in that the damage will be more extensive than the older rotaries, with the apex seal chunks wedging between the rotor and exhaust port, taking out the adjacent irons as well, and raising the cost another $700 above what an older rotary might cost.
As noted after your #2.

Originally Posted by RotaryResurrection
5) your comment about "owners of a $30k car do not expect their engine to produce less power than ratings" has entertainment value for me...almost every owner of a renesis already has an engine that produces less power than even the revised ratings. But, as the whole HP ratings vs. output discussion is a sore subject to the forum gods, I will not take it there on you.
For sure, though there is a big difference between a a car that produces 10 or 20 HP less than advertised and a car that can't even get out of its own way on a hot day.

Last edited by MazdaManiac; Jul 23, 2007 at 02:41 AM.
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Old Jul 23, 2007 | 08:33 AM
  #67  
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Originally Posted by MazdaManiac
Not a necessarily good assumption, based on the "type" of folks that own the RX-8 at this point, but I digress.

such as yourself.
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Old Jul 23, 2007 | 09:42 AM
  #68  
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Originally Posted by mac11
such as yourself.
No, not at all. I would be inclined to rebuild my own motor.
My suggestion (and certainly the ratio of questions to answers on my part and others like me would bear this out) is simply that the average '8 owner is somewhat disinclined to engage in work of that depth.

[[Unless you were being facetious somehow, in which case I'd suggest another attempt!]]
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Old Jul 23, 2007 | 10:12 AM
  #69  
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Originally Posted by MazdaManiac
No, not at all. I would be inclined to rebuild my own motor.
My suggestion (and certainly the ratio of questions to answers on my part and others like me would bear this out) is simply that the average '8 owner is somewhat disinclined to engage in work of that depth.

[[Unless you were being facetious somehow, in which case I'd suggest another attempt!]]
you would be so inclined yet in a couple of years and a couple of motors you have not?
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Old Jul 23, 2007 | 10:25 AM
  #70  
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Originally Posted by mac11
you would be so inclined yet in a couple of years and a couple of motors you have not?
I'm not so sure I can parse that syntax, but I'll make an attempt.

I have destroyed two motors at this point. I intend to destroy at least one more.
However, I don't think I would be labeled a "typical" RX-8 owner. Most do not purchase a new '8 with cash and then take it home and immediately violate the warranty.

My point is that the "typical" '8 owner expects the car to behave like any Honda or Toyota. Comparing "enthusiast" behavior to "consumer" behavior makes no sense.
The OP of this thread is a consumer.
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Old Jul 23, 2007 | 10:28 AM
  #71  
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That doesn't make any difference to the fact you still haven't rebuilt a motor and have had 2 just sitting around.
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Old Jul 23, 2007 | 10:40 AM
  #72  
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I've rebuilt two MSPs for my east-coast people so far, just not for my car. I'll be doing a third in a few weeks (a 4-port).
I've got another 6-port just sitting around, too.
I still don't see your point.

EDIT - OK. I think I understand where you are going and that is my point to RR - it is cheaper and faster to drop in a "junker" than do a full rebuild.
Even a partial rebuild is expensive, but that is what some people want. It is up to the user. I was just pointing out the numbers.
My point to YOU is that the average user can't/won't even do that on his own - he will pay someone else to do the work.

Last edited by MazdaManiac; Jul 23, 2007 at 10:43 AM.
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Old Jul 23, 2007 | 10:48 AM
  #73  
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No my point was that you are certainly one to talk about the "typical RX8 owner" that doesn't rebuild their engine but goes out and buys a junker to drop in instead - for whatever reason.
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Old Jul 23, 2007 | 10:57 AM
  #74  
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I think you are missing my point. Go back and re-read the whole thing.
A typical RX-8 owner won't do either - they just don't have the tools, skills or space and more importantly, they often still have the warranty.
How many folks on this forum (or anywhere, really) do you know that have ripped their own motor out while the car is still under warranty?
How about after the warranty has expired? What percentage of owners do you think that number represents?
Now, out of those (using the numbers provided above) do you think chose a rebuild over a "junker"?
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Old Jul 23, 2007 | 10:59 AM
  #75  
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Originally Posted by MazdaManiac
^^ Use pre-mix, good gas and don't drive it hard in temps above 100°F.
Avoid hi-temp stop and go, too.
If we've got "Good Oil Consumption" [according to you] should we still premix?

Wouldn't above-average [certainly nontypical] consumption indicate a OMP that wouldn't require extra help?
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