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Oil cooler thermostat?

Old 03-02-2009, 06:56 PM
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Originally Posted by MazdaManiac
Are you calling me a Dork because you don't agree or just because I am getting sucked in to this lame argument?
Old 03-02-2009, 07:03 PM
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Originally Posted by olddragger
course you can prove a negative--if anyone doubts that this modification doesnt work, put it on your car, if it doesnt work then they have proved me wrong.
its a "negative" or a "positive" depending on which side of the belief you are. Quit trying to abstract away from the focus.
The proof is in the data. I have the data. The data is either believed or proved wrong. Call or fold?
olddragger
First of all, logically, I can't "prove you wrong".
As I said, "proof" doesn't work like that. Its a logical fallacy.

That said, I have data like yours.
Much more of it.
From multiple cars and multiple setups in a variety of climates and settings.
And the data runs contrary to yours.

I've already posted this stuff.

Your setup works for you. Good.

It just doesn't do so for the reasons you believe it does and, in like circumstances, it does NOT work elsewhere.
So, all you have done, is "prove" that you believe it works.
Old 03-02-2009, 07:14 PM
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MM should be a politician or investment banker.
OD
Old 03-02-2009, 07:21 PM
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MM for President!
Old 03-02-2009, 07:51 PM
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Cool

Originally Posted by MazdaManiac
Gil - you are really out of your depth here. Just let it go.
Not really. We all know how many coolers you put on your car. Did that cut your temps down to n/a Hondas? Geo's? or Corolla's?
Your right I will let it go. After all if Mazda wanted this car to run any cooler they would have done that from the get go. We all know we talk about how stuff works. But unless someone is willing to do and or try something different and it WORKS we will never know. Till then.
TTYL
Old 03-02-2009, 08:10 PM
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I have the RE front bumper and it runs cooler than other 8's on the track.

Especially since I know they don't Rev it as high.

My peak is at 9200, thanks to MM
Old 03-02-2009, 08:30 PM
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Razz, do you run gauges for temp, how do you know for sure?
Old 03-03-2009, 12:46 AM
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Originally Posted by DOMINION
Not really.
Yes, really.
It has nothing to do with any data or anything.
You just aren't equipped to speak with any authority on anything.
You are just one endless non-sequitur after the next.
Old 03-03-2009, 05:36 AM
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Now you still would get the viscosity break down, but in that case typically the base stock would remain. For example if you had a 10W30, in most oils* you would end up with a 30W when the additive package got used up.
It's true, if you speak about synthetics. A 10w-30 mineral oil will be 10w without the additives. It's one of the main advantage of the synthetics, that they don't thinning with the additives are wearing out.

I
have to apologize to the originator of this thread--sorry it got turned around here. You had a good question and maybe we helped answering some of it?
You don't have to apologize! The answer is yes and no.

The Renesis oil cooler thermostat opening temp is 194F, the last FD's 149F.
I would like to know, without any modification, is the average oil temps of the Renesis are higher than the FD's?
If there is a huge difference between the RX-7, RX-8's data, maybe that is the reason for the lot of bearing weared engines. The Mazda raised the average oil temp for efficiency reasons (maybe), and in the same time lowered the preferred oil viscosity, and didn't increase the oil pressure.

I know it's already discussed that a xxw-20 oil is too thin for the Renesis, but there weren't real reasons why?
Why are there so high oil temps causing too thin oil?

Now the Mazda highly (!!!) raised the oil pressure in the Renesis II.

I'm just thinking, if I just know the things that are mentioned above, I have to say, maybe even a xxw-30 is too thin for the Renesis I. I know the 194F not a big matter for an xxw-20 oil too, but 194F at the cooler does not mean, that there aren't much higher oil temperatured point's in the engine.

So is the average oil temps are higher in the Renesis than in the FD?

Last edited by ayrton012; 03-03-2009 at 09:15 AM.
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Old 03-03-2009, 11:01 AM
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as for the comparison --- i have not see any of that data. In speaking with RIck I he recommends a 20W/50 wgt oil in the southeat and no thinner than a 10W/40 anywhere. That is with our engine and the previous ones.
In speaking with Rick he seems more concerned with side seals than anything else in the Renasis. That is with the right oil viscosity. The front bearing etc should not be a problem with the right oil viscosity and in keeping the temps in a sane range. He did say that the 5W/20 oil was crazy and was basically done for the overall "numbers" the manufactor needed.
Rick has talked with us/me for a long time about this engine.
olddragger
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Old 03-03-2009, 11:31 AM
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OD - doesn't the thicker base weight 10w or 20w change (lessen) how much the OMP injects for lub? or is that independent of viscosity?
Old 03-03-2009, 07:08 PM
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to the best of my knowledge the omp is a volume pump so viscosity will not matter
OD
Old 03-04-2009, 02:49 AM
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Originally Posted by olddragger
as for the comparison --- i have not see any of that data. In speaking with RIck I he recommends a 20W/50 wgt oil in the southeat and no thinner than a 10W/40 anywhere. That is with our engine and the previous ones.
In speaking with Rick he seems more concerned with side seals than anything else in the Renasis. That is with the right oil viscosity. The front bearing etc should not be a problem with the right oil viscosity and in keeping the temps in a sane range. He did say that the 5W/20 oil was crazy and was basically done for the overall "numbers" the manufactor needed.
Rick has talked with us/me for a long time about this engine.
olddragger
I didn't want to make a new oil thread, but the 194F oil thermostat gives up the theme again from a new aspect. Mainly if I see that the Mazda raised the oil pump's performance in the Ren II., or I look at the FD,s oil thermostat data.

Otherwise I would like to find the best solution between the high rpm's oil flow, and the best protection (flow) at cold and hot.

I think in street use a xxw-50 oil highly decrease the oil flow at high rpm's, because the bypass valve opens at too low rpms. Of course it is true only if the oil temps are at normal. You will get higher oil temps with the thicker oil, so you made a step forward and backward in the same time.

At the cold side I'm only trust in a 0w or 5w oil. These are far from the ideal thickness (cold) , but the best solution we can find today. Don't forget, the most wear comes from cold startup. ..or too high temps.
Old 03-04-2009, 07:43 AM
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Originally Posted by ayrton012
....I think in street use a xxw-50 oil highly decrease the oil flow at high rpm's, because the bypass valve opens at too low rpms. Of course it is true only if the oil temps are at normal. You will get higher oil temps with the thicker oil, so you made a step forward and backward in the same time....
...say what? ...why would xxx-50 oil decrease flow at high RPMs (vs low RPM)? what has RPM got to do with it?....if the bypass (in the filter?) opens how does that decrease oil flow?...forget RPM...it would increase it, yes? Also...Why would you get higher oil temps w/thicker oil?..heat transfers to whatever viscosity the same, yes? xxx-50 oil doesn't turn to sludge at high RPM or higer temps, it still flows and cools and lubricates.
Old 03-04-2009, 08:26 AM
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Originally Posted by Spin9k
Also...Why would you get higher oil temps w/thicker oil?..heat transfers to whatever viscosity the same, yes? xxx-50 oil doesn't turn to sludge at high RPM or higer temps, it still flows and cools and lubricates.
In general, thinner oils dissipate heat more efficiently than thicker oils, not sure if this is because of higher circulation speed or what other factors may come into play. That's one of the advantages of 5w-20 and 5w-30 oils, along with better cold start protection, especially for impatient Americans who tend to drive their cars hard without letting them warm up properly.
Old 03-04-2009, 10:07 AM
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Originally Posted by Spin9k
...say what? ...why would xxx-50 oil decrease flow at high RPMs (vs low RPM)? what has RPM got to do with it?....if the bypass (in the filter?) opens how does that decrease oil flow?...forget RPM...it would increase it, yes? Also...Why would you get higher oil temps w/thicker oil?..heat transfers to whatever viscosity the same, yes? xxx-50 oil doesn't turn to sludge at high RPM or higer temps, it still flows and cools and lubricates.
There is a bypass valve in the oil line, which opens at a certain pressure to avoid over pressure in the system. If you have a thicker oil, you will reach earlier the opening pressure of this valve in the rpm range, so you can't increase the flow above this point, even if you raise the rpm. That is the problem.
For example at 194F with a xxw-30 you will reach the highest oil flow at 5000rpm and with a xxw-50 you have the biggest flow rate at 3000 rpm. These are not exact data just for show you the difference.
Old 03-04-2009, 10:45 AM
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Originally Posted by ayrton012
There is a bypass valve in the oil line, which opens at a certain pressure to avoid over pressure in the system. If you have a thicker oil, you will reach earlier the opening pressure of this valve in the rpm range, so you can't increase the flow above this point, even if you raise the rpm. That is the problem.
For example at 194F with a xxw-30 you will reach the highest oil flow at 5000rpm and with a xxw-50 you have the biggest flow rate at 3000 rpm. These are not exact data just for show you the difference.
Ok...got it...but still...bypass open sooner sounds better, yes? IOW isn't it better to get max flow due to getting max pressure starting at 3K and on up the RPM range? and not have to wait to 5K? ..is the max flow not the same with both viscosities?

Sounds like the xx-50w oil gets the pressure up sooner, opens the bypass sooner, and gets max flow started at 3K RPM so sooner than w/thin oil. That sounds like a win-win-win no?
Old 03-04-2009, 10:53 AM
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Originally Posted by Spin9k
Razz, do you run gauges for temp, how do you know for sure?
I use the AP.

Plus others have to pull off the track because the temp gage is at max.
Old 03-05-2009, 02:50 AM
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Originally Posted by Spin9k
Ok...got it...but still...bypass open sooner sounds better, yes? IOW isn't it better to get max flow due to getting max pressure starting at 3K and on up the RPM range? and not have to wait to 5K? ..is the max flow not the same with both viscosities?

Sounds like the xx-50w oil gets the pressure up sooner, opens the bypass sooner, and gets max flow started at 3K RPM so sooner than w/thin oil. That sounds like a win-win-win no?
Partly. You have higher pressure with the thicker oil, but you have less flow with it. The pressure itself is not everything. Lubricating is the main aim. One of the most important part of the lubicating is to cool down the internal parts of the engine.

You can improve the lubricating by raising the oil flow. The engine internal part's temps and load are raising with the higher rpm's, so you need more flow in this situation, but you can get it because of the thick oil. Much part of the pumped oil goes back immadeitaly to the oil pan, instead of circulating in the engine.
Old 03-05-2009, 10:09 AM
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Hmmm. Some ineteresting info here. I guess I'll have to get some track data. During some hard running through many miles of mountain roads with steep up and down grades yeiled me and average temp of 204 during weather in teh 60's. This worries me because when I make the same run in the summer it will likely be in the high 90's.

Does anyone know what the temp range is for the RX-8? I got as high as 211 degrees during the last run and I'm afraid on a track my temps will be higher even in this weather because of the lack of high speed straights to cool the car down.
Old 08-05-2009, 11:49 AM
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Interesting info here, Thread revival, yes..

Flash directed me here on the subject of Oil Cooler Thermostats...interesting.

Do they exist?..maybe, possibly on Series I RX-8's, on Series II, not so sure.

Why, Australia is in winter, from a cold engine and within 90 seconds mine are hot to touch, warm at about 20 seconds, IMO can't be a thermostat here...or can there?

I always go by Part Numbers, they never lie and tell the truth.

Is there a "Special" cooler for Germany or Europe?...I doubt it..

England has the same Oil Coolers as the USA and Australia, so why would Germany be special.

USA, UK and Australia..Series I RX-8..
N3H1-14-700D
N3H6-14-700D

Series II RX-8..
N3R1-14-700
N3R2-14-700
Old 08-05-2009, 12:47 PM
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is the thermostat in the primary or second cooler?
I have never seen a oil cooler thermostat--even when looking down into a cooler--guess it could be internal?
I can see them wanting to heat up the oil asap to at least 160F--thats probably more important than getting the coolant warm. I cant imagine a situation in which the oil WONT warm up pretty quickly in an oem car?
My oil coolers too- are warm after just a few minutes and the oil temp is only 160F (at the filter)when checked .
puzzle---that?
i found that the 1989 --91 rx7 does have a thermostat--that opens at 140F?
http://www.teamfc3s.org/main/factory...ion_system.pdf
olddragger

Last edited by olddragger; 08-05-2009 at 12:59 PM.
Old 08-05-2009, 12:59 PM
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Originally Posted by olddragger
is the thermostat in the primary or second cooler?
I have never seen a oil cooler thermostat--even when looking down into a cooler--guess it could be internal?
I can see them wanting to heat up the oil asap to at least 160F--thats probably more important than getting the coolant warm. I cant imagine a situation in which the oil WONT warm up pretty quickly in an oem car?
My oil coolers too- are warm after just a few minutes and the oil temp is only 160F (at the filter)when checked .
puzzle---that?
olddragger
Yeah, I am still yet to be convinced there are any thermostats IN the Coolers themselves..

Yes there is the Eccentric Shaft pellet thermostat....that is all..exact same unit for all rotaries since 1985. FC,FD,FE.


"Run for cover"

Last edited by ASH8; 08-05-2009 at 01:11 PM.
Old 08-05-2009, 01:16 PM
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Originally Posted by ASH8
Yeah, I am still yet to be convinced there are any thermostats IN the Coolers themselves..

Yes there is the Eccentric Shaft pellet thermostat....that is all..

"Run for cover"
The coolers that we cannot remove a bolt and see the themostat we have cut open and seen the thermostat. I tried taking pics this morning but my light was bad.
Attached Thumbnails Oil cooler thermostat?-080509-001.jpg   Oil cooler thermostat?-080509-005.jpg   Oil cooler thermostat?-080509-007.jpg   Oil cooler thermostat?-080509-002.jpg   Oil cooler thermostat?-080509-003.jpg  

Old 08-05-2009, 01:22 PM
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Paul, what Mazda is that off again, and location, I am just trying to visualize , the second pic looks like a separate attachment bracket with two bolt holes. Line in, line out.

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